A2A Cessna 172 User Manual

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C172
ACCU-SIM C172 TRAINER
ACCU-SIM C172 TRAINER
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C172
ACCU-SIM C172 TRAINER

CONTENTS

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22 24
26
30
34
FOREWORD
Cessna 172/Skyhawk — the very definition of a classic aeroplane.
DESIGNER’S NOTES
FEATURES
What you can expect from your A2A Accu-Sim C172 Trainer.
QUICK-START GUIDE
Everything you need to get cleared for take-o as soon as possible.
ACCU-SIM AND THE C172 TRAINER
Experience flight simulation like never before with Accu-Sim.
ACCU-SIM AND THE COMBUSTION ENGINE
The basic principles of how your engine produces power and allows you to fly.
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40
44
48 50
PROPELLERS
What you need to know about the propeller as and Accu-Sim pilot.
SPECIFICATIONS
As a pilot you must always be aware of what your aircra can do … and what it can’t.
NORMAL OPERATIONS
Airspeeds for normal operation of the C172.
CHECKLISTS
Normal operations checklists and procedures for the Accu-Sim C172 Trainer.
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PROCEDURES EXPLAINED
A more in-depth look at the normal operation procedures.
62 68 74
78
92
100
PERFORMANCE CHARTS
What you need to know to plan your flights.
EMERGENCIES
Emergency procedures and checklists.
EMERGENCIES EXPLAINED
A more detailed look at the emergency procedures.
AIRPLANE & SYSTEMS DESCRIPTION
A detailed look at the various parts and systems of the C172.
AIRPLANE HANDLING, SERVICE & MAINTENANCE
Navigating the 2D panels and taking care of your aircra.
CREDITS
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FOREWORD

Cessna 172/Skyhawk — the very definition of a classic aeroplane.
by Mitchell Glicksman ©2013
Merriam /Webster’s dictionary defines “classic” as:
a : serving as a standard of excellence, of recognized value. b : traditional, enduring, i.e., a classic design.
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F ANY AEROPLANE ever deserved to be called “classic”, then the venerable and ubiquitous Cessna 172 in all of its many variations
I
surely deserves that title. It is a time-tested benchmark of aircra ef­ficiency, utility and excellence; it is one of the most recognizable aeroplanes (although sometimes mistaken for its larger and more powerful brother, the Cessna 182/Skylane and vice versa); its value has been and continues to be well-established and constant. The Cessna 172 has endured going- on six decades, and is an undisputedly tradi­tional design. Classic? Q.E.D.
If Piper aircra are “Fords”, based upon William T. Pip­er having been called “The Henry Ford of Aviation”, then Cessna aircra are surely at least “Chevys”. Of course, in both instances I am referring to the smaller, lower pow­ered, single-engine examples, the types of aeroplanes that most private pilots rent or fly as members of a club — Piper’s Tomahawks and Cherokees, and Cessna’s 152s, 162s and, particularly, the venerable 172/Skyhawk.
These Pipers and Cessnas are the aviation industry’s entry-level aeroplanes, just as lower-priced Fords and Chevys are their automotive equivalent (No slight or dis­respect is intended towards any of the other automo­bile manufacturers who also oer excellent entry- level automobiles). It might be hard to find a private pilot who has not taken some dual and/or soloed in a Cessna
172. It is not unusual for many examples of the C-172 to be seen at just about any and every general aviation airport, and this is no surprise. Aer all, in its fiy-seven
is required as well as to what is desired in a basic four­seat aeroplane. While many Cessna aeroplanes have been ground - breaking and highly significant markers in the history of aviation, the simple, straight-forward, and distinctly unspectacular C-172 may be Clyde Cess­na’s and his company’s greatest achievement.
If this is so it is not because the 172 exhibits blinding performance or is so extraordinarily lovely to behold. No, the 172 is a modest and ordinary looking aero­plane, an eicient short-hauler with moderate-payload and range. Stable and pilot-friendly it is also surpris­ingly nimble and quick on the controls when needs be. The 172 is a mostly docile (except for a sharp stall break under certain conditions), some might say pedestrian aeroplane, purposely designed to be able to be flown safely even by the dimmest bulb on the pilot tree. Not a fast cruiser or a rapid climber, it is, however, an hon­est, solid and reliable aircra, neither overly forgiving
year production history, since November 1955 when the first C-172 was introduced to the public, over 60,000 of these versatile aeroplanes have been built, making it the most numerous aeroplane ever pro­duced, by far.
All during its 57 year run (with no sign of going away) it has been one of the most eco­nomical, utilitarian, versatile, aordable, safe and easy to fly aeroplanes ever produced, not to mention one of the most popular, most reliable and relied upon of all general aviation aeroplanes. This, too, is no surprise. For all of these years the Cessna 172 has been a relaxing, fun, simple and relatively inexpensive aero­plane to fly and operate. Ad­ditionally, the C-172 in its vari­ous forms has and still serves in the U. S. Border Patrol and Civil Air Patrol for search and rescue missions as well as in over a dozen foreign air forces since its introduction.
All of this has not come about by chance. The Cessna 172 is an example of what can be achieved by intelligent com­promise and attention to what
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FOREWORD
Photos of the 1937-38 Luscomb 8a
nor overly challenging. Accordingly, it is one of the best choices for both VFR and IFR training. With its high wing, granting an unobstructed downwards view, it is ideal for sightseeing, aerial photography and for patrol and surveillance duties.
FBOs and flying clubs love 172s because there are always excellent examples available in the market for purchase/lease, they are reasonably priced, cost eec­tive to operate, are durable, and if well-maintained, hold their value well. Parts are plentiful and available but, as it is with all aeroplanes, they may be expensive depending upon which part(s) is/are needed. Pilots new to the 172 find that they oer no unpleasant surprises, are a quick study and require little time to check out in. They have an excellent safety record, keeping hull and liability insurance premiums to the minimum. They are not fuel guzzlers and can withstand a lot of pilot abuse. Renters find that they are not walletbusters, either.
On the debit side, 172s cabins are snug with lim­ited shoulder and headroom for all but the smallest and slightest people. “Full sized” adults will find them an uncomfortable or even prohibitively small environ­ment. Like many “four-seat” GA aeroplanes, the 172’s average 900 lb. useful load does not permit full tanks plus four hey adults on board. With standard tanks (43 gal.) on board, only 642 lbs. of available load remains. Of course, if you and your friends weigh an average of no more than 160 lbs. or so each, no worries. In the real world (my world, anyway) this may not be the case.
172s are slow; there is no way around it. It’s a 120k (138 m.p.h.) aeroplane and that is all. Fully loaded it may climb at 600-700 fpm at sea level. The cabin is loud, even at cruise settings the engine produces a distinc­tive and pervasive low-midrange drone that makes ca­sual conversation in the air without an intercom system somewhat diicult. However, from the “R” model for­ward, some attention to cabin soundproofing has been addressed.
Of the 60K Cessna172/Skyhawks that have been built since its debut in November 1955, more than 20,000 of those which remain are based and flying in the United States; the rest are scattered over virtually every corner of the world.
THE RISE OF A CLASSIC AEROPLANE
So then, from where and whence did this ubiquitous work horse of the general aviation fleet come?
Anyone seeking proof that evolution exists need look no further than the Cessna 172. Its design is a mélange, hybrid and accumulation of those designs of a number of previously successful aeroplanes. Many histories of this aeroplane start from the point when Cessna decided to put a nose wheel on their popular 170 model; but that does not go back far enough. It is clear that many of the specific design characteristics of the 172 gradually took shape and form from its immediate predecessors going back to just aer World War II. The 172’s real forefathers are the humble 120/140/140A models, the elementary, 85-90 h.p., single engine, high wing, two seat tail wheel aeroplanes which came into this world in 1946 as part of the virtually univer sally predicted General Aviation (GA) boom which so many supposed would blossom and thrive aer World War II as a matter of course, but which never happened.
You see, the makers of general aviation aeroplanes thought and to be fair, not without sound reason, that thousands of returning military pilots would be more than anxious to jump at the chance of owning and flying their own aeroplanes now that they had experienced (on Uncle Sam’s dime, if you please) the “wonderful world of flying”. Sounds good, right? Wrong.
The real story which the virtually drooling aer-war aeroplane manufacturers did not ken was that for all too many of these brave and valiant pilots their experi­ences in the air during the war ran from deadly dull to just deadly; and with not much in between. Fortunately, most service pilots’ closest brush with the Grim Reaper
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whilst flying came from being bored to death on seem­ingly endless flights of all kinds in all kinds of turbulence and rough weather during which their most ardent, fer­vent wish was to return safely, and soon to terra firma, the more firma the less terra.
For those far fewer souls who found themselves, mostly by o - regretted choice, in harms way at alti­tude, the experience of flying was mostly as described by U. S. M. C. Colonel Gregory “Pappy” Boyington: “Fly­ing is hours and hours of boredom sprinkled with a few seconds of sheer terror.” Enough said.
So, between the recently bored and/or terrified ex­aeroplane jocks a far smaller realistic potential clien­tele for Pipers, Taylorcras, Cessnas, Stinsons and the like than had been so optimistically imagined actually existed. Still, aer the enthusiastic, if unrealistic, post­war glut on the market of various GA aircra types and makes, a few managed to survive, some by virtue of the brilliance of their design, most by virtue of the fact that they were relatively inexpensive to own and operate.
In 1946, aviation fuel cost around US .20 per gallon (worth approximately US$2.50 in 2013). This was not too bad; better anyway than the just over US$6.00 for 100LL in most places in the U.S. in 2013. In 1946, a brand new Cessna 120 cost a bit over US$3,000.00 (worth approxi­mately US$37,198.00 in 2013); just about the price of a
new, well-equipped BMW 3-Series 328i Sedan or Buick LaCrosse Hybrid Sedan (before taxes, etc.) in 2013.
For comparison, in 2013 1946 Cessna 120s in good condition were advertised for between a low of US$17,000.00 and a high of US$30,000 depending upon engine and propeller TBO, radios, etc. installed.
THE CESSNA 120/140 –WHERE IT BEGINS.
Piper, Taylorcra, Stinson and others had been produc­ing light, two-seat, high wing aeroplanes before the war slightly altering these aeroplanes for military use by the services to great eect. Cessna, however, which had seen its T-50 light twin used to great eect by the services as the AT-17 multi-engine trainer as well as building 750 Waco CG­4A-CE assault gliders of D-Day fame, had no similar light single of its own at war’s end and therefore has to start from scratch to catch up to the others. Looking around for ideas, Cessna was sure to notice Don Luscomb’s excellent 1937 “8” series “Silvaire”, an aeroplane widely used in the pre-war and wartime Civilian Pilot Training Program. (un­important information: the very first aeroplane I ever flew and trained in was a Luscomb 8A on floats). Numerous dis tinct design similarities between the Luscomb 8 and the 120/140 are surely more than coincidental.
So, the great controversy continues; was the Cessna 120 a budget model of the 140, or was the 140 the de­luxe model of the 120? While there are some distinct dierences between them - the original 140 has flaps (albeit somewhat questionable as to eectiveness), and small “D” windows a of the main side windows, as well as an electrical system which includes a starter - it was not long before many 120s got retrofitted with, you guessed it, “D” windows, an electrical system w/ starter, and in some cases, flaps.
All original 120/140s had C-85 Continental four cylin­der horizontally opposed engines and fixed-pitch pro­pellers of the cruise (lower pitch) or climb (higher pitch) variety.
As they came from the factory in 1946, the wings of the Cessna 120/140 were fabric covered; however, most
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Photos of the 1946 Cessna 120
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1948 Cessna 140
have by now been since converted to metal covering. Li struts extending from the bottom of the fuselage to the wing s were of the “V” two-strut design. In 1948 the 140’s instrument panel was updated from the old 30’s/40’s central cluster (clutter?) to something resem­bling a useful layout.
THE CESSNA 140A – THE TRUE ANCESTOR OF THE 172 EMERGES.
In 1949, disappointed by the poor sales and the short customer lines of returning aviators (see above) Cessna updated the 140 and the “A” model was introduced. The fuselage and interior were le unchanged; however
some real aerodynamic improvements were included such as an entirely new semi- tapered wing for better roll response; and still a bit later, replacement of the original thin-chord, ineectual flaps (which is why there is little practical aeronautical dierence between the 120 and the 140) with slightly shorter but deeper real Fowler flaps, which finally gave the 140’s flaps some au­thority.
(The Fowler type flap’s trailing edge flap extends rearward of the wings as it descends on special tracks. When deployed, wing area, camber and chord are in­creased and if there is a slot, or opening at the hinge line to allow airflow over the top of the flap, boundary-layer control may be improved. Fowlers provide the most li per sq. . of surface of any type of flap; however, they require a complicated linkage system and mechanism.)
At the same time that Fowler flaps were installed, the powerplant was upgraded to the Continental C-90, 90 h.p. engine.
A big step on the way to the 172 was the new wing. The fabric covering of the 140A’s original wing was re­placed with a new design which was covered with stressed aluminum, stiening the entire structure and thus permitting a single li strut per wing rather than the dual “V”, two-strut design of the 120/140. Addition­ally, the ailerons were lengthened and ran the length of the tapered outer-wing section and the wing tips were changed from rounded to what was thought to be a more modern-looking squared o shape.
Also, the 140A received an improvement in its land­ing gear. The 1946 120/140s already had the familiar Cessna flat spring leaf steel, main landing gear legs. While the materials used and the exact design of
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The 1950C-140A
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1948 Cessna 170
Cessna’s landing gear legs have changed from steel leaf to tapered tubular spring over time, their profile and general appearance have remained essentially unchanged. The 140A had toe brakes which were not at all common in light aeroplanes at that time. Cessna was afraid that pilots new to this kind of brake control system would nose the 140A over too easily by braking too hard. Accordingly, the main gear was moved for­ward to put the C. G. farther behind the main wheels. Later, some 120s and 140s were retrofitted with land­ing gear extension modifications which moved their wheels forward as well. Pilots being the myriad, multi­farious, magpies that they are, some have managed to nose over their 140As anyway.
Around 525 140As were built, including a few C­140A “Patroller” types, anticipating the 1949 L-19 (O-1) “Birddog”, a derivative of the C-170. The “Patroller” was designed for use by police departments, who had vast areas of highway to patrol, such as are found in and around the deserts of the southwest U.S. They had see­through Plexiglas doors, 42 gallon fuel tanks for long range/long loitering time; and most curiously, a tube in the floor which could ostensibly be utilised for dropping messages and/or for more basic biological necessities.
The Cessna 140 has a special place in the hearts of all of those (me) who were first introduced to the re­ality that we could actually go flying by the late and much missed Frank Kingston Smith who, amongst his many books and magazine articles, wrote the delightful “Weekend Pilot”. Therein he tells of how as a much be­leaguered young Philadelphia attorney in the mid 1950s he almost succumbed to a depressing syndrome of ul­cers and emotional dysfunction but for his accidental,
but literally life-saving and life-changing introduction to and involvement with aviation. The airplane he bought and learned to fly in was a Cessna 140.
The Cessna 120/140 is one of the most gentle and forgiving of the classic tailwheel aeroplanes; however, interestingly (balingly), a few 140As have been spotted with nose wheel conversions, turning them into sort-of Cessna 150s. Most ironically, there are and have been for some time a number of companies oering a tail­wheel conversion for the Cessna 150/152 turning them into sort-of Cessna 140A’s! Madness, I say; madness.
THE CESSNA 170 – GETTING CLOSER TO HOME.
Given the time it takes for design development and pro­totype testing, the C-170, introduced to the public on 27 February 1948, a year before the debut of the C-140A, it is clear that as early as 1947 that Cessna was already committed to producing a four-seat version of their 120/140 models.
Like the 120/140, the new C-170 was initially pro­duced with an all-metal fuselage and fabric-covered wings which had no dihedral and were called “straight­wings”. The fin/rudder had no dorsal fin. The engine was upgraded to the reliable flat, six-cylinder, horizontally opposed 145hp Continental C-145-2 (later the O -300A) with three of the C-140’s fuel tanks totaling 42 US gal­lons installed in the wings to accommodate the larger engine. The li struts were the same “V”, two- strut de­sign as on the 120/140. In every way, this new aeroplane was just a slightly larger 120/140; but changes were to come soon which would transform this aeroplane into the father of the 172.
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Photos of 1950
Cessna 170A
THE CESSNA 170A - ARE WE THERE YET?
There is every reason to suspect that the initial C-170 was a temporary and somewhat hastily produced aeroplane because before the year was out, Cessna introduced the much slicker and more sophisticated C-170A. The fin/rudder now had a dorsal fin and was identical to that of the already established C-190/195 aircra which were introduced in 1947. This aero plane sported a new wing, now covered with metal and with slightly larger flaps. While these flaps were not yet the more eective “Fowler” flaps to come on the C-170B, they could be lowered to a whopping 50º! Like the C-170’s wing, this new wing had no dihe
dral; accordingly, the C-170 and C-170A are called the “straight-wing” 170s.
In 1952 the pen-ultimate variant of the 170, the C­170B was introduced and production of this aeroplane continued until 1956, the year of the first C-172. The C­170B was a massive and distinct refinement of the 170 model and set the stage for all of the subsequent C-172 s which were soon to begin to appear.
Larger “Fowler” flaps, first seen on the C-140A and which were also used on the L-19 ‘Birddog” introduced in 1950 were installed in the C-170B’s new wing. These were termed “Para-Li flaps” by Cessna, but are more commonly called “barn door flaps”. They initially could be lowered to 20º, 30º and 40º; however, beginning in 1955 an additional 10º flap setting for short-field take­os was added.
Other aerodynamic refinements included a newly designed stabilizer/elevator with an increased aero­dynamic balance area at the tips which incorporated within them an internal mass balance which reduced el­evator control pressure. Also, in 1955, the rounded rear side windows were changed to be more square shaped, and a new, more durable type of tailwheel bracket was installed.
All of these refinements much improved the C-170; however the most significant and longest lasting refine­ment was the wing. The “B”’s new wing became the
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standard wing of all Cessna light single-engine aircra, including the C-172, and is still incorporated to this day. The wing incorporated all of the previous refinements such as a stressed- skin metal covering, etc., and consists of a constant 64” chord NACA 2412 centre section from
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centerline outward to 100”, at that point tapering to 44-
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inch chord NACA 2412 section at 208” from centerline. This new wing also now had 3º of dihedral with threeº washout (forward twist) across the tapered section only to prevent wing-tip from stalling before the wing-root. All of these refinements were carried over to the C-172 and have appeared on all subsequent 172 models. The 172 was now only one step away from birth.
THE CESSNA 170C – ALMOST THERE, KIDS.
In January 1955, while the scene was set and lit and the curtain seemed just about ready to rise on the Cessna 172, there was one more slight detour; the C-170C. Not quite ready to abandon its latest and most successful aeroplane, Cessna modified the C-170 one more time
creating the C-170C. The 145 hp Continental C-145-2 engine used in all previous C-170s was replaced with the more modern flat six-cyl­inder, horizontally opposed, Con­tinental 0-300-A. The O-300 is es­sentially a modernized C-145 and has the same dimensions, weight, bore, stroke, displacement, com­pression ratio and output. Both the C-145 and O-300 use a direct, un-geared drive to the propeller and produce approximately 145 h.p. Many pilots appreciate and are pleased by the smoothness of the six-cylinder O-300, but are less than pleased at their increased overhaul bill caused by the extra two cylinders.
The tail surfaces were once again revised to incorporate an even larger stabilizer/elevator (still with the same aerodynamic and mass balances of the C-170B) and
a very businesslike, “modern” squared-o fin/rudder. This became the C-172’s tail section.
While this aeroplane was promoted as the latest and the greatest of the C-170 series, Cessna had a trick card up its sleeve, and it was an ace. On 12 June 1955, Cessna unveiled what it had undoubtedly been working on for a long time -- the first tricycle gear Cessna -- the C-170C now had a nosewheel!
The 170’s FAA type certificate initially included an additional provision for a “C-172” , which was done to reduce usual bureaucratic certification time and fees. Aer overwhelming approval of the tricycle geared 170 by the aviation community, a separate type certificate was applied for and received for the new Cessna 172.
TOP: Photo of 1952 C-170B
BOTTOM LEFT: Photo of early 1960’s era Army L-19 Birddog
BOTTOM RIGHT: Photo of Vietnam-era Air Force L-19/0-1 Birddog
Photos of 1955 Cessna 170C
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FOREWORD
1955 Cessna 172
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THE CESSNA 172/SKYHAWK
- HOME AT LAST.
“Everything old is new again.”
The early to mid -1950’s were yet another in the long series of periods of change in aviation since the Broth­ers started the whole shabang at Kitty Hawk on a frigid morning on December 17, 1903. It sometimes seems that there are no periods other than periods of change in aviation; but no matter. This time the big change was from GA aircra with tailwheels to those with nose­wheels.
tiss pushers of the early 1900s most presciently sported tricycle landing gear, i.e., having a wheel at the nose instead of one at the tail, that particular landing gear
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configuration was diicult to design into an airframe where the engine and its systems take up virtually all of the available space in the very front of the fuselage. The first military aircra with a nosewheel produced in large numbers is believed by this author to have been the Consolidated PBY “Catalina” amphibious light bomber/patrol aircra, which first flew in March, 1935. However, there was an even earlier GA aeroplane with a nosewheel (aer the early Curtiss’), the W-1 designed by Fred Weick and flown in 1934. Other early GA aeroplanes with a nosewheel were the Stearman-Hammond Y-1 of 1936, followed by another, more famous Fred Weick de-
While some of the pioneering and innovative Cur-
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sign, the “Ercoupe” first flown in October. 1937.
By 1938 aer thousands of expensive and sometime fatal nose - overs of their tailwheel aircra, the U. S. Army Air Corps was ready to try a new idea in a military
Early nosewheeled aircraft:
▶ Replica 1910
Curtiss “Pusher”
▶ W.W. II era Consolidated
PBY”Catalina” ▶ 1934 Weick W-1 ▶ 1936 Stearman-
Hammond Y-1 ▶ 1937 Weick (Forney)
“Ercoupe”
▶ An early Me-262
aeroplane; it was ready for aeroplanes with nose wheels and the beginning of a new era in aviation commenced. What followed were the P-38 “Lightning” -27 Jan. 1939; the P-39 “Airacobra” -April, 1939; the B-24 “Liberator”­mid-1939 (the first A. A. C. bomber with a nosewheel, the B-17 being the last A. A. C. bomber without one); B-25 “Mitchell” - late 1939; the B-26 “Marauder”-Nov. 1940. Of course, once the jet-age began, tailwheels were as useful as…well, whatever is not very useful (although, interestingly, the first operational jet fighter, the Messer­schmitt Me-262 was first designed and test - flown with conventional tailwheel landing gear).
Aer World War II makers of GA aircra soon followed the lead of the military. In 1951 Piper introduced its it’s first tricycle landing gear aeroplane, the four-seat PA-22 Tri-Pacer. It was a huge success and it surely challenged
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FOREWORD
1951 Piper “Tripacer”
and tasked Cessna to step up and to introduce a tricycle geared aeroplane of its own. Additionally, the impetus for Cessna to produce a factory tri - gear 170 possibly came because of the well - known tri - gear STC (Supple­mental Type Certificate) for the 172 developed by Met­Co-Air in Fullerton, California, a modification which was being made by many C-170 owners.
In July 1955 the aeroplane destined to become one of the most beloved in its class, the Cessna 172, was in­troduced to the public, touted to now be equipped with “Land - O - Matic” (tri - cycle) landing gear. An overnight
sales success, more than 1,400 were built and sold dur­ing the first year aer its unveiling. Cessnas all-metal and far sleeker - appearing entry into the tri - gear race was more appealing to many than the fabric - covered, and to many stodgy and foreshortened - looking Piper Tri - Pacer.
Aer the C-172’s appearance and huge success, the GA “nosewheel revolution” continued throughout the rest of the ‘50s and into the 60’s until very few GA air­cra, except for special types intended for aerobatics, crop dusting, bush and rough country flying and other specific utility purposes were still being manufactured with tailwheels.
1960 saw a new swept - back tail on the C-172A which looked rakish, but didn’t actually increase per­formance in any way. In 1961 the first C-172 was avail­able as a “Skyhawk”, an upscale, more luxurious ver­sion of the C-172B. However, aer a short while, all C-172s were popularly called “Skyhawks” and the dis­tinction gradually dissolved until 1977, when all C-172s were then and thereaer oicially and simply named “Skyhawks”.
A major change in the fuselage structure and in the overall appearance of the C-172/Skyhawk came in 1963, one year aer the same modification was made
Photo of 1961 C-172A/Skyhawk
Cessna 172/Skyhawk w/ new fuselage
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to the C-182 and to Cessna’s single-engine flagship, the C-210 with the dropped rear fuselage and inclusion of a wraparound rear-view window. Not being an aero­plane likely to ever be involved in aerial combat, un­obstructed vision to the rear might be seen by some as being somewhat superfluous in the 172; but it looked modern, added welcome light and a feeling of extra spaciousness to what is in the fastback versions of the aeroplane a fairly cramped and formerly claustropho­bic environment.
While the original C-172 evolved and was altered over the years as to its appearance (swept fin/rudder, rear view window), available equipment, electronics, soundproofing, landing gear length and construction, control refinements, engine swops, experiments with cantilever wings, retractable landing gear, as well as plans for diesel and electric power; it has always re­mained what it was from the first: a reliable, utilitarian and good- mannered flying machine for four moderate­ly sized people to fly for moderate distances at moder­ate altitudes and airspeeds.
Not an aeroplane which exhibits spectacular perfor­mance numbers, the C-172 nevertheless just keeps on doing what it has done from the first, which is to pro­vide the ordinary private pilot with an excellent, if most moderate way to go aviating; and you know, sometimes moderation is the wisest practice aer all, which during its 43 years and counting, the ever-popular Cessna 172 has well and truly proved.
1959 Cessna 175/Skylark
Photo of 1957 Cessna 180
SIBLINGS AND RELATIONS
THE CESSNA 175/SKYLARK
By 1958, the popularity and commercial success of the C-172/Skyhawk was firmly established. Cessna perceived that there was market for a more powerful C-172 but was unwilling to risk its star seller’s reputa­tion and “brand” recognition by going too far in alter­ing the basic design. Accordingly a new Cessna, the C-175 was developed.
Intended to take its place between the heavier and more powerful Cessna 180 and the C-172/Skyhawk, the C-175 and the “Skylark”, a more luxurious version, was intended to be both close enough and dierent enough to the “Skyhawk” to maintain a familial connection. The powerplant chosen was the Continental GO-300 which is a geared and beefed up 175 h.p. version of the 145 h.p. Continental C-145 engine which powered the Skyhawk. This turned out to be a poor choice of engine. Because it is essentially a 145 h.p. engine pushed to put out 30 more horsepower by gearing the propeller, its TBO (time between overhaul) is only 1,200 hours of operation, whist the un-geared C-145 (O-300)’s TBO is within the industry standard at 1,800 hours.
While there are a number of structural details that dier from the C-172/Skyhawk to accommodate its greater power and weight, the C-175/Skylark looks much like the C-172/Skyhawk, except for a distinct
bulge in the cowling to make room for the rather large and bulky engine gear box. This at least makes the C-175/Skylark an excellent choice for a rather tricky “name that plane” contest.
The C-175/Skylark was not a successful aeroplane for Cessna. Firstly, it did not much improve the C-172/Sky­hawk’s performance all that much. Those who desired the spectacular and legendary performance of a C-180 simply chose it instead, and those who desired a C-180 with tricycle gear chose the C-182/Skylane. Secondly, the C-175/Skylark’s ill-starred GO-300 engine was, per­haps hastily and unfairly perceived to be unreliable, possibly because of its low TBO, and accordingly the C-175/Skylark was largely ignored. Eventually realising that it had clearly made a serious marketing mistake, Cessna wisely dropped the aeroplane from its produc­tion lines aer only four years of tepid sales.
THE CESSNA REIMS - FR172J “REIMS ROCKET”
Built in the mid ‘60s through the mid ‘70s by the French aviation company known alternatively as “So cietè Nouvelle Max Holste, and “Reims Aviation”, the pleasantly named FR172J “Reims Rocket” is essen tially a heavily modified C-172F. Reims Aviation also produced modifications of other Cessna aircra: F150 , F152, F172, F177, F182, F337, and the Reims-Cessna F406 “Caravan”.
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FOREWORD
The Rocket was powered by a fuel-injected, Conti­nental IO-360D of 210h.p. (takeo), 195 h.p. (continu­ous) which was built by Rolls Royce, with a constant speed, controllable propeller, which is also basically the same powerplant that is installed in the twin-engined Cessna 336/337 series.
It was the first 172 to have electrically operated flaps instead of the former manual, lever-operated flaps (which I personally like a lot better). The Re ims Rocket was the prototype aircra for the further
1972 Cessna “Reims Rocket
1965 T-41A,B “Mescalero”
modified U. S. A. F. T-41A “Mescalero” primary trainer (see below).
THE T-41A,B “MESCALERO” – U.S. AIR FORCE PRIMARY TRAINER
In 1964 the U.S. Air Force chose the C-172A to be the aeroplane used for Undergraduate Pilot Training (UPT), later called Initial Military Flight Screening (IMFS) air-
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cra, naming it the T-41A. The Air Force rightly figured that if a prospective Flight Training Cadet could not learn to fly this most docile and forgiving aeroplane in a fairly short time, then he or she was not a likely candi­date for their most rigourous flight - training program, of which your author has some practical knowledge.
The T-41A “Mescalero”, named aer the “Mescalero Apache” tribe of New Mexico, was initially a stock 172. The following year the Air Force, influenced by the in­creased performance of the Cessna Reims - FR172J “Re­ims Rocket”, modified the T-41A with the installation of the same 210h.p. (takeo), 195 h.p. (continuous) Con­tinental IO-360 engine, with a constant-speed control­lable propeller in place of the stock 145hp Continental O-300 and its 7654 fixed-pitch propeller, as was installed in the factory C-172A. This was the T-41B.
Additionally, in 1968 the U. S. Air Force acquired 52 T­41Cs, which had the same engine as the T-41B but with a fixed-pitch climb propeller for the Air Force Academy in Colorado Springs, Colorado, a climb propeller be­ing most useful in that largely vertical territory. Three of these remain at the school and are used by, among others, the Academy’s prestigious show -flying team. A later “D” model of this aeroplane included more sophis­ticated avionics including a proprietary military TACAN (Tactical Air Navigation System) receiver; essentially a hyper-accurate VOR/DME.
The T-41 in its various incarnations was the U.S. Air Force’s Initial Military Flight Screening (IMFS) aircra until 1993, when it was gradually phased out in place of the ill-fated and too-occasionally deadly Slingsby T-3A Firefly. The Air Force has since utilised the Diamond DA20 for this purpose.
1980 R172K Hawk XP on oats
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R172K HAWK XP
Built both in Wichita and Reims between 1977 and ’81, had a fuel injected, Continental IO-360K (IO-360KB) a 210 h.p. engine which was soon derated to 195 h.p. to increase its TBO from 1,500 hours in 1977/ early ’78 to 2,000 hours thereaer, with a constant speed, control­lable propeller. The Hawk XP was basically Cessna’s homegrown answer to the French Reims Rocket and could cruise at 131 knots as opposed to the plain-jane 172’s 120 k cruise. This slight increase in speed was not considered by some to be worth the extra purchase price and operating costs.
However, the one place that the R172K Hawk XP re­ally shines is on the water. A standard 172 is not power­ful enough to be an eective four-passenger floatplane;
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Photos of 1980 Cessna 172RG “Cutlass
however, the Hawk XP on floats is one of GA’s nicest four-seat floatplanes, with its excellent takeo perfor­mance and cruise speed of around 125K, which is very good for a floatplane in its class. (more unimportant in­formation; I oen flew a Hawk yea’ years ago from the old, now long gone and much missed “Suburban Sea­plane Base” in Island Park, N.Y., located near the Long Beach /Island Park Bridge; and it was a class act with lots of get up and go).
the 120 knot C-172 go faster. To do so cost US$19,000 more than the standard 172 so that the landing gear would get out of the way of the oncoming air. How ever, at the end of the day, the RG’s best cruise speed is only 140 knots compared to the 120 or so knots cruise of the standard and much less expensive 172. The extra expense of purchase, maintenance and an nual inspection of a C-172 with retractable gear was not greeted with enthusiasm by many. Additionally, for some, the idea of an aeroplane with wing struts
THE CESSNA 172RG “CUTLASS”
Sometimes humourously (or maybe, not so humour­ously) called the 172 “RRR” (Pirates, Cutlass…what­ever), the “RG” stands for the fact that this 172’s landing gear retracts. Introduced in 1980 and actually appearing on the Cessna 175’s FAA type certificate, the 172 RG is oicially considered to be a variant of the C-175 and not of the C-172. It is powered by the venerable Lycoming O-360-F1A6 engine of 180 h.p. (also the familiar powerplant of the Piper “Coman che 180”, “Archer” and many others), with a constant­speed, controllable propeller. The idea was to make
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hanging out in the breeze and retractable gear seems and looks preposterous, and perhaps it is.
In any event, the C-172RG was a case of not enough go for the buck; and, accordingly, it did not find much favour in the mass GA market. The beginning of a world­wide slump in new GA aircra sales in 1980 didn’t help, either. The RG found a small niche for itself, however, in flight schools which found it to be a relatively low-cost aeroplane for giving pilots the requisite complex aircra
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(controllable propeller - retractable landing gear) expe­rience necessary to obtain a Commercial Pilot’s Certifi­cate in the U.S.
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FOREWORD
NOTEWORTHY FLIGHTS
LONGEST TIME IN THE AIR WORLD’S RECORD FLIGHT
As part of a clever and spectacular fund- raising scheme for the Damon Runyon Cancer Fund, Robert Timm and John Cook took o from McCarran Airfield, Las Vegas, NV in Cessna 172 N9172B on December 4, 1958. What was dierent and newsworthy about this particular takeo was that the next landing did not occur until 64 days, 22 hours, 19 minutes and 5 seconds had elapsed when they landed back at McCarran Airfield on February 4, 1959.
Timm and Cook pulled up all personal necessaries, such as food, water with buckets on ropes and through the specially made accordion door on the passenger’s side from a truck, which drove at full throttle down a long, straight road with the Cessna flying overhead and matching its speed. Fuel was taken on board through a hose, which first fed a special auxiliary fuel tank in the belly of the aeroplane which, in turn, fed the two wing tanks. Extra oil was carried on board and fed to the en­gine through a hole in the instrument panel and firewall.
To accommodate all those cans of oil and other liv­ing necessaries, there was only room in the snug and
crowded cabin for the pilot’s seat. A so, roll-up pad was used as sleeping accommodations for the pilot not on duty.
Problems arose early in the flight when the electric generator, which was driven by the engine, failed. Un­daunted by this setback, the innovative Timm and Cook called for and hauled up a wind - driven generator from an Aeronca Champion, duct-taped it to the right wing strut and plugged it into the aeroplane’s cigarette light­er receptacle, thereby providing electric power for the remainder of the flight, which went without a further hitch.
Once they knew that they had broken the world’s record for endurance in flight, the pilots wisely decided to end their flight as their faithful Cessna’s beleaguered and tired engine was, aer over 1,500 hours of continu­ous operation, starting to lose power. Near the end of the flight, the exhausted 172 could hardly climb away aer refueling and before all ended in tragedy, the time to call it quits was clearly on hand.
This world’s record breaking Cessna 172 can be seen on display in the passenger terminal at McCarran Inter­national Airport, Las Vegas, Nevada.
TO RUSSIA WITH LOVE
On 28 May 1987 at approximately 7:00 p.m., 18 (or pos­sibly 19) year - old Mathias Rust, a German pilot with only around 50 hours of flight experience, flew a rented German - registered Reims Cessna F172P, D-ECJB from Helsinki-Malmi Airport through Soviet airspace to a landing on a bridge near St. Basil’s Cathedral in Red Square, Moscow, U. S. S. R. Rust was detected by but not stopped by Soviet air defense forces.
As it happens, Mr. Rust was luckier than he could have hoped for in that the overhead electric trolly wires that usually run along and above the bridge were un­der repair and had been taken down on the morning of the day he landed there and were replaced the next day. Aer a successful landing, Rust then taxied o the bridge, past the famous Cathedral and came to a stop about 100 metres from the entrance to Red Square. His
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approach and landing was videotaped by a British doc­tor. Rust was promptly arrested, tried and sentenced to 4 years in a labour camp. However, he did not actually serve out his sentence in a labour camp, but instead at the far less rigourous high security Lefortovo temporary detention facility in Moscow. Rust had served less than one year of his sentence, when he was released by order of General Secretary Mikhail Gorbachev in August 1988 as a gesture of good will to the west.
YOUR CESSNA 172R SKYHAWK
This is the aeroplane that almost never was. In fact, there almost were never any more light Cessna aeroplanes built aer 1985. In the mid 1980s, the economy in the United States was in very bad shape, something we know all about again today. Also, a spate of what some might consider unwise, unreasonable and draconian decisions by various courts regarding product liability had crippled manufacturers of light aircra such as Cessna and had rendered their businesses untenable. Accordingly, un­able to thrive in such a hostile insurance climate, Cessna simply closed up shop. Almost ten years went by, but in 1994 President Clinton signed the General Aviation Re­vitalization Act, which eased and limited the manufac­turer’s liability with regard to accidents in which there occurred monetary or property damage and/or personal injury as a result of the operations of a light GA aeroplane.
The result was that in 1995, a new C-172, the “R” model would be produced. This new 172 was an im­provement over the last 172, the “N”, built in 1985, in that the “R” has the larger fuel injected Textron Lycom­ing IO-360-L2A engine. The last 172, the “N” had the smaller, carburetted Lycoming O-320. This Lyc 360 was
de-rated from its usual average 180 h.p. to produce only 160 h.p., which means that it lasts longer and has a greater TBO. Also, the injected Lyc I0-360 produces maximum power at only 2,400 r.p.m. ,making it quieter and more fuel eicient than the faster- turning Lyc 320.
The “R” got a complete interior make-over with ver­tically adjustable, contoured, reclining, 26g seats and an inertia-reel seat belt/harnesses (a responsive echo from the old product liability lawsuits), an eicient multi-level ventilation system (always an important fea­ture for flight simmers), an intercom system for all four seats, and extensive soundproofing which was sorely needed in the aeroplane’s previously overly-loud inte­rior environment.
Structurally, the “R” received stainless steel control cables, dual vacuum pumps, epoxy corrosion protec­tion, larger fuel tanks, tinted windows, better, back-lit, non-glare instruments, a systems annunciator panel, optional wheel fairings, and more radio package choic­es including GPS or IFR GPS.
An upgraded version, the 172S Skyhawk SP was of­fered in 1998 with the full-power Lyc IO-360 rated at 180 h.p., a larger propeller and a leather interior.
Not a generic “C-172”, A2A has specifically modelled every aspect of the C-172R in every detail using the tre­mendous amounts of information of all kinds which were derived from the pilots on our sta’s extensive real-world flying of an excellent example of the Cessna 172R. Taking all of that information, we modelled the most authentic and accurate flight-sim Cessna 172R available, both visually and in its flight characteristics. We do this because we have a passion for flying which we want to share with you. Enjoy!
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DESIGNER’S NOTES

VER TEN YEARS ago, A2A (then Shockwave
Productions) entered the flight simulation scene with strong opinions of what was needed in our flight simulation industry.
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And thus, began our quest to unwind and re-define what the word “simulation” truly means. Today and over a decade later, we have released a new airplane, the Accu-Sim C172 Trainer. This is one of our most ambi tious and important projects to date.
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The month preceding the public release of this air­cra brought a new challenge, and that was “how do we show our customers what this product is?” Everywhere we look, we see brand new substance. While the Cessna 172 is a simple aircra to operate, reproducing and sim­ulating all of the building blocks of this machine is not. The conversations we’ve been having with many com­panies and people in aviation were dierent than most were used too, because here comes this ambitious com­pany A2A having to understand aspects of an airplane that pilots, mechanics, and even many engineers don’t have to know. But we do, because we must produce the exact same product in a dierent world. The wonderful and magical world of flight simulation.
Soon you will be reading and possibly participating in discussions within our simulation community that are virtually identical to the conversations taking place right now throughout the aviation communities, with questions like “what oil do you recommend during the winter months?” “How do you like that propeller?” “Do you lean your engine by ear or using the EGT gauge (ex­haust gas temperature)?”
Your Accu-Sim airplane has been developed as we go back and forth from the airport to our development workstations. Not only does the aircra and its systems persist from flight to flight, even engine temperatures persist. So if you land at an airport on a cold day, park the plane, turn your computer o, grab lunch and return an hour later, you will find an engine that is still warm. If you wait until the next morning to fly, it will be what
is known as “cold soaked.” However, if you plugged in your electric engine heater you can come back anytime and find a nice, warm engine waiting for you. Warm up times will be much shorter, and your engine will actu­ally last longer. This is what aircra owners talk about, and do.
However, probably the most ambitious new feature in the Accu-Sim C172 Trainer is the Pre-Flight Inspection (a virtual walk-around). You can now, more than ever, visu­ally see the state of the airplane. You can check for water in the fuel, inspect various hinges, check the oil, tires, and even wiggle the flaps by hand to see how secure they are. In fact, this walk around system is so complete, that we could hand this product to a future pilot who has never even gotten close to a Cessna 172 and a week later, ask him or her to perform a pre-flight inspection on the real aircra. The result would be a person with a solid under­standing of what parts and systems need to be checked and why, and this would have all been learned without realizing it since it was, in this case, interactive and fun.
“Fun” is a key word to learning and has been the core of Accu-Sim since its inception. To be truly immersed in a simulation, is to truly have fun. This is who we are, flight simmers. We block out the world around us and want to get ourselves lost in an alternate reality. This is simula­tion. But it must be true. When you do something as simple as turn an ignition key and engage a starter, there are things you can expect to happen…. physical things. Much of our interpretation of the physical world around us is known to us, subconsciously. We instinctively know when something looks and feel right and conversely, when something “just doesn’t seem right.” During our development of our Accu-Sim aircra, we are continually looking, probing, and testing all kinds of combinations of things to make sure the physical world in Accu-Sim is as true as we can make it to the natural world we all live in.
Pilots and aircra enthusiasts are a discerning, sen­sitive bunch. We’re tough to please, which helps define who we are. We welcome everyone to the new Accu­Sim C172 Trainer. We hope you get not just hours, but months if not years of growth and enjoyment from it.
THE AIR TO AIR SIMULATIONS TEAM
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FEATURES

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What you can expect from your A2A Accu-Sim C172 Trainer.
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 Experience one of the world’s most
popular trainer airplanes.
 Pure3D Instrumentation now with natural 3D
appearance with exceptional performance.
 Designed for both professional commer-
cial pilot training and entertainment.
 Immersive pre-flight inspection system designed
by pilots while operating the actual Cessna 172.
 A true propeller simulation.
 Electric starter with accurate cranking power.
 Dynamic ground physics including both
hard pavement and soft grass modeling.
 Primer-only starts are now possible. Accu-Sim
monitors the amount of fuel injected and it’s effectiveness to start and run the engine.
 Persistent airplane where systems, cor-
rosion, and temperatures are simu­lated even when the computer is off.
 Immersive in-cockpit, physics-driven sound
environment from A2A engineered recordings.
 Complete maintenance hangar inter-
nal systems and detailed engine tests including compression checks.
 Piston combustion engine modeling. Air comes
in, it mixes with fuel and ignites, parts move, heat up, and all work in harmony to produce the wonderful sound of a Lycoming 360 engine. Now the gauges look beneath the skin of your aircraft and show you what Accu-Sim is all about.
 A total audible cockpit and ound engi-
neered by A2A sound professionals.
 In cockpit pilot’s map for handy
in-flight navigation.
 Authentic fuel delivery includes prim-
ing and proper mixture behavior. Mix­ture can be tuned by the book using the EGT or by ear. It’s your choice.
 All models include A2A specialized materials
with authentic metals, plastics, and rubber.
 Airflow, density and its temperature not
only affect the way your aircraft flies, but how the internal systems operate.
 Real-world conditions affect system condi-
tions, including engine temperatures.
 Spark plugs can clog and eventually foul if
the engine is allowed to idle too low for too long. Throttling up an engine with oil-soaked spark plugs can help clear them out.
 Overheating can cause scoring of cylinder head
walls which could ultimately lead to failure if warnings are ignored and overly abused
 Engine, airframe, cockpit panel and individual
gauges tremble from the combustion engine.
 Authentic drag from the airframe and flaps
 Authentic Bendix King Avionics stack includ-
ing the KMA 26 Audio Panel, two KX 155A NAV/COMMS, KR 87 ADF, KT 76C Transpon­der, KN 62A DME, and K AP 140 Two Axis Autopilot with altitude pre-selection.
 Three in-sim avionics configurations including
no GPS, GPS 295, or the GNS 400. Built-in, auto­matic support for 3rd party GNS 430 and 530.
 As with every A2A aircraft, it is gorgeously con-
structed, inside and out, down to the last rivet.
 System failures, including flaps that can
independently jam or break based on the actual forces put upon them. If you deploy your flaps at too high a speed, you could find yourself in a very dangerous situation.
 Authentic battery. The battery capac-
ity is based on temperature. The major draw comes from engine starting.
 Oil pressure system is affected by oil vis-
cosity (oil thickness). Oil viscosity is af­fected by oil temperature. Now when you
 Designed and built to be flown “By The Book.”
 Visual Real-Time Load Manager, with the ability
to load fuel, people, and baggage in real-time.
 Four naturally animated passengers that
can sit in any seat including the pilot’s.
start the engine, you need to be care­ful to give the engine time to warm
 Eight commercial aviation sponsors have
supported the project including Phil­lips 66 Aviation, Champion Aerospace, and Knots2u speed modifications.
 3D Lights ‘M’ (built directly into the model).
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QUICK-START GUIDE

Everything you need to get cleared for take-off as soon as possible.
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HANCES ARE, IF you are reading this manual, you have properly installed the A2A Accu-Sim C172 Trainer. Howev­er, in the interest of customer support,
C
here is a brief description of the setup process, system requirements, and a quick start guide to get you up quickly and eiciently in your new aircra.
SYSTEM REQUIREMENTS
The A2A Simulations Accu-Sim C172 Trainer requires the following to run:
▶ Requires licensed copy of
Lockheed Martin Prepar3D
▶ Service Pack 2 (SP2) required
NOTE: while the A2A Accu-Sim C172 Trainer may work with SP1 or earlier, many of the features may not work correctly, if at all. We cannot attest to the accuracy of the flight model or aircra systems under such condi tions, as it was built using the SP2 SDK. Only Service Pack 2 is required. The Acceleration expansion pack is fully supported but is NOT REQUIRED.
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OPERATING SYSTEM:
▶ Windows XP SP2 ▶ Windows Vista ▶ Windows 7 ▶ Windows 8
PROCESSOR:
▶ 2.0 GHz single core processor (3.0GHz and/or
multiple core processor or better recommended)
HARD DRIVE:
▶ 250MB of hard drive space or better
VIDEO CARD:
▶ DirectX 9 compliant video card with at least 128
MB video ram (512 MB or more recommended)
OTHER:
▶ DirectX 9 hardware compatibility and audio
card with speakers and/or headphones
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QUICK-START GUIDE
INSTALLATION
Included in your downloaded zipped (.zip) file, which you should have been given a link to download aer purchase, is an executable (.exe) file which, when accessed, contains the automatic installer for the soware.
To install, double click on the ex­ecutable and follow the steps pro­vided in the installer soware. Once complete, you will be prompted that installation is finished.
IMPORTANT: If you have Microso Se- curity Essentials installed, be sure to
make an exception for Lockheed Mar tin Prepar3D as shown on the right.
REALISM SETTINGS
The A2A Simulations Accu-Sim C172 Trainer was built to a very high de­gree of realism and accuracy. Be­cause of this, it was developed using the highest realism settings avail­able in Lockheed Martin Prepar3D.
The following settings are rec­ommended to provide the most ac­curate depiction of the flight model. Without these settings, certain fea­tures may not work correctly and the flight model will not perform ac­curately. The figure below depicts the recommended realism settings for the A2A Accu-Sim C172 Trainer.
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FLIGHT MODEL
To achieve the highest degree of real­ism, move all sliders to the right. The model was developed in this manner, thus we cannot attest to the accuracy of the model if these sliders are not set as shown above. The only excep tion would be “Crash tolerance.”
INSTRUMENTS AND LIGHTS
Enable “Pilot controls aircra lights” as the name implies for proper control of lighting. Check “Enable gyro dri” to provide realis­tic inaccuracies which occur in gyro compasses over time.
“Display indicated airspeed” should be checked to provide a more realistic simulation of the air­speed instruments.
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ENGINES
Ensure “Enable auto mixture” is NOT checked. The Spitfire has a fully working automatic mixture control and this will interfere with our extensively documented and modeled mixture system.
FLIGHT CONTROLS
It is recommended you have “Auto-
rudder” turned o if you have a means of controlling the rudder input, either via side swivel/twist on your specific joystick or rudder pedals.
ENGINE STRESS DAMAGES ENGINE
(Acceleration Only). It is recom­mended you have this UNCHECKED.
QUICK FLYING TIPS
 To Change Views Press A or SHIFT + A.
 Keep the engine at or above 800 RPM. Fail-
ure to do so may cause spark plug fouling. If your plugs do foul (the engine will sound rough), try running the engine at a higher RPM. You have a good chance of blowing them clear within a few seconds by doing so. If that doesn’t work, you may have to shut down and visit the maintenance hangar.
 On landing, once the airplane settles
slowly pull back on the stick for addi­tional elevator braking while you use your wheel brakes. Once the airplane has slowed down you can raise your flaps.
 Be careful with high-speed power-on dives
(not recommended in this type of aircaft), as you can lose control of your aircraft if you exceed the max allowable speed.
 For landings, take the time to line up
and plan your approach. Keep your eye on the speed at all times.
 Using a Simulation Rate higher than
4× may cause odd system behavior.
 A quick way to warm your engines is to
re-load your aircraft while running.
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ACCU-SIM AND THE C172 TRAINER

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Experience flight simulation like never before with Accu-Sim.
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CCU-SIM IS A2A Simulations’ growing flight simulation engine, which is now connectable to oth­er host simulations. In this case,
A
we have attached our Accu-Sim C172 Trainer to Lockheed Martin Prepar3D to provide the maximum amount of realism and immersion possible.
WHAT IS THE PHILOSOPHY BEHIND ACCU-SIM?
Pilots will tell you that no two air­cra are the same. Even taking the same aircra up from the same airport to the same location will re-
sult in a dierent experience. For
example, you may notice one
day your engine is running a
bit hotter than usual and
you might just open your
cowl flaps a bit more and be on your way, or maybe this is a sign of something more serious devel­oping under the hood. Regardless, you expect these things to occur in a simulation just as they do in life. This is Accu-Sim, where no two flights are ever the same.
Realism does not mean having a diicult time with your flying. While Accu-Sim is created by pilots, it is built for everyone. This means ev­erything from having a professional crew there to help you manage the systems, to an intuitive layout, or just the ability to turn the system
on or o with a single switch. How­ever, if Accu-Sim is enabled and the needles are in the red, there will be consequences. It is no longer just an aircra, it’s a simulation.
ACTIONS LEAD TO CONSEQUENCES
Your A2A Simulations Accu-Sim air­cra is quite complete with full sys­tem modeling and flying an aircra such as this requires constant at­tention to the systems. The infinite changing conditions around you and your aircra have impact on these systems. As systems operate both inside and outside their limita­tions, they behave dierently. For example, the temperature of the air that enters your carburetor has a direct impact on the power your engine can produce. Pushing an engine too hard may produce just slight damage that you, as a pilot, may see as it just not running quite as good as it was on a previous flight. You may run an engine so hot,
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ACCU-SIM AND THE C172 TRAINER
that it catches fire. However, it may not catch fire; it may just quit, or may not run smoothly. This is Accu­Sim – it’s both the realism of all of these systems working in harmony, and all the subtle, and sometimes not so subtle, unpredictability of it all. The end result is when flying in an Accu-Sim powered aircra, it just feels real enough that you can almost smell the avgas.
YOUR AIRCRAFT TALKS
We have gone to great lengths to bring the internal physics of the air frame, engine, and systems to life. Now, when the engine coughs, you can hear it and see a pu of smoke. If you push the engine too hard, you can also hear signs that this is happening. Just like an actual pilot, you will get to know the sounds of your aircra, from the tires scrubbing on landing to the stresses of the airframe to the window that is cracked opened.
BE PREPARED – STAY OUT OF TROUBLE
The key to successfully operating al­most any aircra is to stay ahead of the curve and on top of things. Air
Aircraft persistence is one of the key features of Accu­Sim. Maintain your C172 from ight to ight in the Maintenance Hanger.
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cra are not like automobiles, in the sense that weight plays a key role in the creation of every component. So, almost every system on your aircra is created to be just strong enough to give you, the pilot, enough margin of error to operate safely, but these mar gins are smaller than those you find in an automobile. So, piloting an aircra requires both precision and respect of the machine you are managing.
It is important that you always keep an eye on your oil pressure and engine temperature gauges. On cold engine starts, the oil is thick and until it reaches a proper operating temperature, this thick oil results in much higher than normal oil pressure. In extreme cold, once the engine is started, watch that oil pressure gauge and idle the engine as low as possible, keeping the oil pressure under 120psi.
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PERSISTENT AIRCRAFT
Every time you load up your Accu­Sim C172 Trainer, you will be flying the continuation of the last aircra which includes fuel, oil, coolant levels along with all of your system
conditions. So be aware, no longer will your aircra load with full fuel every time, it will load with the same amount of fuel you le o when you quit your last flight. You will learn the easy or the hard way to make, at the very least, some ba­sic checks on your systems before jumping in and taking o, just like a real aircra owner.
Additionally, in each flight things will sometimes be dierent. The gauges and systems will never be exactly the same. There are just too many moving parts, variables, changes, etc., that continuously al­ter the condition of the airplane, its engine and its systems.
NOTE:
Signs of a damaged engine may be lower RPM (due to increased friction), or possibly hotter engine temperatures.
SOUNDS GENERATED BY PHYSICS
Lockheed Martin Prepar3D, like any piece of soware, has its limi­tations. Accu-Sim breaks this open by augmenting the sound system with our own, adding sounds to provide the most believable and im-
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mersive flying experience possible. The sound system is massive in this Accu-Sim C172 Trainer and includes engine sputter / spits, bumps and jolts, body creaks, engine detona­tion, runway thumps, and flaps, dy­namic touchdowns, authentic sim­ulation of air including bueting, shaking, broken flaps, primer, and almost every single switch or lever in the cockpit is modeled. Most of these sounds were recorded from the actual aircra and this sound environment just breaks open an entirely new world. However, as you can see, this is not just for enter­tainment purposes; proper sound is critical to creating an authentic and believable flying experience. Know that when you hear something, it is being driven by actual system phys­ics and not being triggered when a certain condition is met. There is a big dierence, and to the simula­tion pilot, you can just feel it.
GAUGE PHYSICS
Each gauge has mechanics that al­low it to work. Some gauges run o of engine suction, gyros, air pres­sure, or mechanical means. The RPM gauge may wander because of the slack in the mechanics, or the gyro gauge may fluctuate when starting the motor, or the gauge needles may vibrate with the motor or jolt on a hard landing or turbulent buet.
The gauges are the windows into your aircra’s systems and there­fore Accu-Sim requires these to be­have authentically.
LANDINGS
Bumps, squeaks, rattles, and stress all happens in an aircra, just when it is taxiing around the ground. Now take that huge piece of lightweight metal and slam it on the pavement. It’s a lot to ask of your landing gear. Aircra engineer’s don’t design the landing gear any more rugged than they have too. So treat it with kid gloves on your final approach. Kiss the pavement. Anything more is just asking too much from your aircra.
Accu-Sim watches your landings, and the moment your wheels hit the pavement, you will hear the ap propriate sounds (thanks to the new sound engine capabilities). Slam it on the ground and you may hear metal
The gauges are the windows into your aircraft’s systems and therefore Accu­Sim requires these to behave authentically.
Don’t get lazy
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on approach! Every landing is a challenging with Accu-Sim.
crunching, or just kiss the pavement perfectly and hear just a nice chirp or scrub of the wheels. This landing system part of Accu-Sim makes every landing challenging and fun.
YOUR TURN TO FLY SO ENJOY
Accu-Sim is about maximizing the joy of flight. We at A2A Simulations are passionate about aviation, and are proud to be the makers of both the A2A Simulations Accu-Sim C172 Trainer, and its accompanying Ac­cu-Sim expansion pack. Please feel free to email us, post on our forums, or let us know what you think. Shar­ing this passion with you is what makes us happy.
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ACCU-SIM AND THE COMBUSTION ENGINE

The piston pulls in the fuel / air mixture, then compresses the mixture on its way back up.
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The spark plug ignites the compressed air / fuel mixture, driving the piston down (power), then on it’s way back up, the burned mixture is forced out the exhaust.
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HE COMBUSTION ENGINE is basically an air pump. It creates power by pulling in an air / fuel mixture, igniting it, and turning the explosion into usable power. The explosion
T
pushes a piston down that turns a crank­sha. As the pistons run up and down with controlled explosions, the cranksha spins. For an automobile, the spinning cranksha is connected to a transmis­sion (with gears) that is connected to a drivesha, which is then connected to the wheels. This is liter­ally “putting power to the pavement.” For an aircra, the cranksha is connected to a propeller sha and the power comes when that spinning propeller takes a bite of the air and pulls the aircra forward.
The basic principles of how your engine produces power and allows you to fly.
The main dierence between an engine designed for an automobile and one designed for an aircra is the aircra engine will have to produce power up high where the air is thin. To function better in that high, thin air, a supercharger can be installed to push more air into the engine.
OVERVIEW OF HOW THE ENGINE WORKS AND CREATES POWER
Fire needs air. We need air. Engines need air. Engines are just like us as – they need oxygen to work. Why? Because fire needs oxygen to burn. If you cover a fire, it goes out because you starved it of oxygen. If you have ever used a wood stove or fireplace, you know when you open the vent to allow more air to come in, the fire will burn more. The same principle applies to an engine. Think of an engine like a fire that will burn as hot and fast as you let it.
Look at these four images on the le and you will un­derstand basically how an engine operates.
The piston pulls in the fuel / air mixture, then com­presses the mixture on its way back up.
The spark plug ignites the compressed air / fuel mix­ture, driving the piston down (power), then on it’s way back up, the burned mixture is forced out the exhaust.
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ACCU-SIM AND THE COMBUSTION ENGINE
AIR TEMPERATURE
Have you ever noticed that your car engine runs smoother and stronger in the cold weather? This is because cold air is denser than hot air and has more oxygen. Hotter air means less power.
MIXTURE
Just before the air enters the com­bustion chamber it is mixed with fuel. Think of it as an air / fuel mist.
A general rule is a 0.08% fuel to air ratio will produce the most pow­er. 0.08% is less than 1%, meaning for every 100 parts of air, there is just less than 1 part fuel. The best economical mixture is 0.0625%.
Why not just use the most economical mixture all the time?
Because a leaner mixture means a hotter running engine. Fuel actually acts as an engine coolant, so the richer the mixture, the cooler the engine will run.
However, since the engine at high power will be nearing its maxi­mum acceptable temperature, you would use your best power mix­ture (0.08%) when you need power (takeo, climbing), and your best economy mixture (.0625%) when throttled back in a cruise when en­gine temperatures are low.
So, think of it this way:
▶ For HIGH POWER, use
a RICHER mixture.
▶ For LOW POWER, use
a LEANER mixture.
WEAK
STRONG
THE MIXTURE LEVER
Most piston aircra have a mix­ture lever in the cockpit that the pilot can operate. The higher you fly, the thinner the air, and the less fuel you need to achieve the same mixture. So, in general, as you climb you will be gradually pull ing that mixture lever backwards, leaning it out as you go to the high er, thinner air.
How do you know when you have the right mixture?
The standard technique to achieve the proper mixture in flight is to lean the mixture until you just no­tice the engine getting a bit weaker, then richen the mixture until the engine sounds smooth. It is this threshold that you are dialing into your 0.08%, best power mixture. Be aware, if you pull the mixture all the way back to the leanest position, this is mixture cuto, which will stop the engine.
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Cold air is denser and so provides more oxygen to your engine. More oxygen means more power.
Just before the air enters the combustion chamber it is mixed with fuel. Think of it as an air / fuel mist. When you push the throttle forward, you are opening a valve allowing your engine to suck in more fuel / air mixture.
INDUCTION
As you now know, an engine is an air pump that runs based on timed explosions. Just like a forest fire, it would run out of control unless it is limited. When you push the throttle forward, you are opening a valve allowing your engine to suck in more fuel / air mixture. When at full throttle, your engine is pulling in as much air as your intake system will allow. It is not unlike a watering hose – you crimp the hose and re­strict the water. Think of full power as you just opening that water valve and letting the water run free. This is 100% full power.
In general, we don’t run an air­plane engine at full power for ex­tended periods of time. Full power is only used when it is absolutely necessary, sometimes on takeo, and otherwise in an emergency sit­uation that requires it. For the most part, you will be ‘throttling’ your motor, meaning you will be be set­ting the limit.
MANIFOLD PRESSURE = AIR PRESSURE
You have probably watched the weather on television and seen a large letter L showing where big storms are located. L stands for
LOW BAROMETRIC PRESSURE
(low air pressure). You’ve seen the H as well, which stands for HIGH BAROMETRIC PRESSURE (high air pressure). While air pressure changes all over the world based on weather conditions, these air pres­sure changes are minor compared to the dierence in air pressure with altitude. The higher the altitude, the much lower the air pressure.
On a standard day (59°F), the air pressure at sea level is 29.92Hg BAROMETRIC PRESSURE. To keep things simple, let’s say 30Hg is stan­dard air pressure. You have just taken o and begin to climb. As you reach higher altitudes, you notice your rate of climb slowly getting lower. This is because the higher you fly, the thinner the air is, and the less power your engine can pro­duce. You should also notice your
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MANIFOLD PRESSURE decreases as you climb as well.
Why does your manifold pressure decrease as you climb?
Because manifold pressure is air pressure, only it’s measured in­side your engine’s intake manifold. Since your engine needs air to breath, manifold pressure is a good indicator of how much power your engine can produce.
Now, if you start the engine and idle, why does the manifold pressure go way down?
When your engine idles, it is being choked of air. It is given just enough air to sustain itself without stalling. If you could look down your car­buretor throat when an engine is idling, those throttle plates would look like they were closed. However if you looked at it really closely, you would notice a little space on the edge of the throttle valve. Through that little crack, air is streaming in. If you turned your ear toward it, you could probably even hear a loud sucking sound. That is how much that engine is trying to breath. Those throttle valves are located at the base of your carburetor, and
your carburetor is bolted on top of your intake manifold. Just below those throttle valves and inside your intake manifold, the air is in a near vacuum. This is where your manifold pressure gauge’s sensor is, and when you are idling, that sensor is reading that very low air pressure in that near vacuum.
As you increase power, you will notice your manifold pressure comes up. This is simply because you have used your throttle to open those throttle plates more, and the engine is able to get the air it wants. If you apply full power on a normal engine, that pressure will ultimately reach about the same pressure as the outside, which really just means the air is now equalized as your en
­gine’s intake system is running wide open. So if you turned your engine o, your manifold pressure would rise to the outside pressure. So on a standard day at sea level, your manifold pressure with the engine o will be 30”.
IGNITION
The ignition system provides timed sparks to trigger timed explo­sions. For safety, aircra are usu­ally equipped with two completely
The air and fuel are compress by the piston, then the ignition system adds the spark to create a controlled explosion.
independent ignition systems. In the event one fails, the other will continue to provide sparks and the engine will continue to run. This means each cylinder will have two spark plugs installed.
An added advantage to having two sparks instead of one is more sparks means a little more power. The pilot can select Ignition 1, Igni­tion 2, or BOTH by using the MAG switch. You can test that each igni­tion is working on the ground by selecting each one and watching your engine RPM. There will be a slight drop when you go from BOTH to just one ignition system. This is normal, provided the drop is within your pilot’s manual limitation.
ENGINE TEMPERATURE
All sorts of things create heat in an engine, like friction, air temp, etc., but nothing produces heat like
COMBUSTION.
The hotter the metal, the weaker its strength.
Aircra engines are made of alu­minum alloy, due to its strong but lightweight properties. Aluminum maintains most of its strength up to about 150°C. As the temperature approaches 200°C, the strength starts to drop. An aluminum rod at
The hotter the metal, the weaker its strength.
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0°C is about 5× stronger than the same rod at 250°C, so an engine is most prone to fail when it is run­ning hot. Keep your engine tem­peratures down to keep a healthy running engine.
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ACCU-SIM AND THE COMBUSTION ENGINE
LUBRICATION SYSTEM (OIL)
An internal combustion engine has precision machined metal parts that are designed to run against other metal surfaces. There needs to be a layer of oil between those surfaces at all times. If you were to run an engine and pull the oil plug and let all the oil drain out, aer just minutes, the en gine would run hot, slow down, and ultimately seize up completely from the metal on metal friction.
There is a minimum amount of oil pressure required for every en­gine to run safely. If the oil pressure falls below this minimum, then the engine parts are in danger of making contact with each other and incur­ring damage. A trained pilot quickly learns to look at his oil pressure gauge as soon as the engine starts, because if the oil pressure does not rise within seconds, then the engine must be shut down immediately.
Above is a simple illustration of a cranksha that is located between two metal caps, bolted together. This is the very cranksha where all of the engine’s power ends up. Vital oil is pressure-injected in between these surfaces when the engine is run­ning. The only time the cranksha ever physically touches these metal caps is at startup and shutdown. The moment oil pressure drops below its minimum, these surfaces make con­tact. The cranksha is where all the power comes from, so if you starve this vital component of oil, the en­gine can seize. However, this is just one of hundreds of moving parts in an engine that need a constant sup­ply of oil to run properly.
Without the layer of oil between the parts, an engine will quickly overheat and seize.
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MORE CYLINDERS, MORE POWER
The very first combustion engines were just one or two cylinders. Then, as technology advanced, and the demand for more power in­creased, cylinders were made larg­er. Ultimately, they were not only made larger, but more were added to an engine.
Below are some illustrations to show how an engine may be configured as more cylinders are added.
The more cylinders you add to an engine, the more heat it pro­duces. Eventually, engine manu­facturers started to add additional
“rows” of cylinders. Sometimes two engines would literally be mated together, with the 2nd row being ro­tated slightly so the cylinders could get a direct flow of air.
THE PRATT & WHITNEY R4360
Pratt & Whitney took this even fur­ther, creating the R4360, with 28 Cylinders (this engine is featured in the A2A Boeing 377 Stratocruiser). The cylinders were run so deep, it became known as the “Corn Cob.” This is the most powerful piston aircra engine to reach production. There are a LOT of moving parts on this engine.
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The “Corn Cob,” the most powerful piston aircraft engine to reach production.
TORQUE VS HORSEPOWER
Torque is a measure of twisting force. If you put a foot long wrench on a bolt, and applied 1 pound of force at the handle, you would be applying 1 foot-pound of torque to that bolt. The moment a spark triggers an explo sion, and that piston is driven down, that is the moment that piston is cre ating torque, and using that torque to twist the cranksha. With a more powerful explosion, comes more torque. The more fuel and air that can be exploded, the more torque. You can increase an engine’s power by ei ther making bigger cylinders, adding more cylinders, or both.
Horsepower, on the other hand, is the total power that engine is creat ing. Horsepower is calculated by com­bining torque with speed (RPM). If an engine can produce 500 foot pounds of torque at 1,000 RPM and produce the same amount of torque at 2,000 RPM, then that engine is producing twice the horsepower at 2,000 RPM than it is at 1,000 RPM. Torque is the twisting force. Horsepower is how fast that twisting force is being applied.
If your airplane has a torque me­ter, keep that engine torque within the limits or you can break internal components. Typically, an engine produces the most torque in the low to mid RPM range, and highest horsepower in the upper RPM range.
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PROPELLERS

What you need to know about the propeller as and Accu-Sim pilot.
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EFORE YOU LEARN about how dierent propellers work, first you must understand the basics of the common airfoil, which is the reason why a wing creates li, and in this case, why a propel-
B
It is interesting to note when discussing Bernoulli and Newton and how they relate to li, that both theories on how li is created were presented by each man not knowing their theory would even­tually become an explanation for how li is created.
They both were dealing with other issues of their day.
ler creates thrust.
THE BERNOULLI THEORY
This has been the traditional theory of why an airfoil creates li: Look at the image above which shows you how the shape of an airfoil splits the oncoming air. The air above is forced to travel further than the air at the bottom, essentially stretching the air and creating a lower pressure, or vacuum. The wing is basically sucked up, into this lower pressure. The faster the speed, the greater the li.
THE NEWTON THEORY
As the air travels across the airfoil’s upper and lower surfaces, li is created by BENDING the air down with great force at its trailing edge, and thus, the Newtonian force of opposite and equal reaction apply.
WHAT WE DO KNOW (AND WHAT THE PILOT NEEDS TO KNOW)
The airfoil is essentially an air diverter and the li is the reaction to the diverted air. An airfoil’s li is de pendent upon its shape, the speed at which it is trav­eling through the air, and its angle to the oncoming air (angle of attack).”
It is important that you note that we have delib­erately not entered into the details and complete aerodynamics involved with either of the above ex planations for li as they go beyond the scope of this manual.
Unfortunately over time, the Bernoulli theory spe­cifically has been misrepresented in many textbooks causing some confusion in the pilot and flight training community. Misrepresentations of Bernoulli such as the “equal transit theory” and other incorrect variations on Bernoulli have caused this confusion. Rather than get into a highly technical review of all this we at A2A sim­ply advise those interested in the correct explanation of Bernoulli to research that area with competent authority.
For the purposes of this manual, A2A just wants you to be aware that both Bernoulli and Newton represent complete explanations for how li is created.
The main thing we want to impress upon you here is that when considering li and dealing with Bernoulli and Newton, it is important and indeed critical to understand that BOTH explanations are COMPLETE EXPLANA
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TIONS for how li is created. Bernoulli and Newton do NOT add to form a total li force. EACH theory is simply a dierent way of COMPLETELY explaining the same thing.
BOTH Bernoulli and Newton are in fact in play and
acting simultaneously on an airfoil each responsible completely and independently for the li being created
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on that airfoil.
Hopefully we have sparked your interest in the direc­tion of proper research.
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PROPELLERS
WHAT IS A STALL?
In order for a wing to produce ef­ficient li, the air must flow com­pletely around the leading (front) edge of the wing, following the contours of the wing. At too large an angle of attack, the air cannot con­tour the wing. When this happens, the wing is in a “stall.”
Typically, stalls in aircra oc­cur when an airplane loses too much airspeed to create a sui­cient amount of li. A typical stall exercise would be to put your air­cra into a climb, cut the throttle, and try and maintain the climb as long as possible. You will have to gradually pull back harder on the stick to maintain your climb pitch and as speed decreases, the angle of attack increases. At some point, the angle of attack will become so great, that the wing will stall (the nose will drop).
STALL
The angle of attack has become too large. The boundary layer vortices have separated from the top surface of the wing and the incoming flow no longer bends
Stall. A wing that is stalled will be unable to create signicant lift.
completely around the leading edge. The wing is stalled, not only creating little li, but significant drag.
CAN A PROPELLER STALL?
What do you think? More on this below.
LIFT VS ANGLE OF ATTACK
Every airfoil has an optimum angle at which it attacks the air (called angle of attack, or AoA), where li is at it’s peak. The li typically starts when the wing is level, and increases until the wing reaches its optimum angle, lets say 15-25 de­grees, then as it passes this point, the li drops o. Some wings have a gentle drop, others can actually be so harsh, as your angle of attack increases past this critical point, the li drops o like a cli. Once you are past this point of li and the angle is so high, the air is just being plowed around in circles, creating almost no li but plenty of drag. This is what you experi­ence when you stall an aircra. The bueting or shaking of the aircra at this stall position is actually the turbulent air, created by your stall­ing wing, passing over your rear
Look at the cross section of a propeller blade. Essentially, the same process creates lift.
LEFT: Level Flight. A wing creating moderate lift. Air vortices (lines) stay close to the wing. RIGHT: Climb. Wing creating signicant lift force. Air vortices still close to the wing.
stabilizer, thus shaking the air­cra. This shaking can sometimes become so violent, you can pop rivets and damage your airframe. You quickly learn to back o your stick (or yoke) when you feel those shudders approaching.
Notice in the diagram on the next page, how the airfoil creates more li as the angle of attack in
­creases. Ideally, your wing (or pro­peller) will spend most of it’s time moving along the le hand side of this curve, and avoid passing over the edge. A general aviation plane that comes to mind is the Piper Cherokee. An older version has what we call a “Hershy bar wing” because it is uniform from the root to the tip, just like an Hershy choc
­olate bar. Later, Piper introduced the tapered wing, which stalled more gradually, across the wing. The Hershy bar wing has an abrupt stall, whereas the tapered wing has a gentle stall.
A propeller is basically a wing except that instead of relying on incoming air for li, it is spinning around to create li, it is perpendic­ular to the ground, creating a back­wards push of air, or thrust. Just remember, whether a propeller is
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a fixed pitch, variable pitch, or con­stant speed, it is always attacking a variable, incoming air, and lives within this li curve.
FROM STALL TO FULL POWER
With brakes on and idling, the angle at which the prop attacks the still air, especially closer to the propeller hub, is almost al ways too great for the prop to be creating much li. The prop is mostly behaving like a brake as it slams it’s side into the air. In real ity, the prop is creating very little li while the plane is not moving. This eect is known as prop stall, and is part of the Accu-Sim prop physics suite.
Once done with your power check, prepare for takeo. Once you begin your takeo run, you may notice the aircra starts to pull harder aer you start rolling forward. This is the propeller start ing to get its proper “bite” into the air, as the propeller blades come out of their stalled, turbulent state and enter their comfortable high li angles of attack it was designed for. There are also other good physics going on during all of
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these phases of flight, that we will just let you experience for the first time yourself.
PROP OVERSPEED
A fixed speed prop spends almost all of it’s life out of it’s peak thrust angle. This is because, unless the aircra is travelling at a specific speed and specific power it was designed for, it’s either operating too slow or too fast. Lets say you are flying a P-40 and have the pro­peller in MANUAL mode, and you are cruising at a high RPM. Now you pitch down, what is going to happen? The faster air will push your prop faster, and possibly be­yond it’s 3,000 RPM recommended limit. If you pitch up your RPM will drop, losing engine power and pro­peller eiciency. You really don’t have a whole lot of room here to play with, but you can push it (as many WWII pilots had to).
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SPECIFICATIONS

As a pilot you must always be aware of what your aircraft can do … and what it can’t.
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HIS SECTION OUTLINES the capabili­ties and limitations of your Accu-Sim C172 aircra. Learning this informa­tion is of vital importance if you are
T
to successful master the aircra, while ignoring it will likely lead to many trips to the Maintenance Hang­er for repairs.
PERFORMANCE SPECIFICATIONS
Note that high speed figures are with wheel fairings. Subtract 2 kias when removed. Performance data is supplied for the “R” (or “160 HP”) model only.
SPEEDS
▶ Maximum at Sea Level: 123 ktas ▶ Cruise, 80% Power at 8000 ft: 122 ktas
RANGE
Recommended lean mixture with fuel allowance for en­gine start, taxi, takeo, climb and 45 minutes reserve.
▶ 80% Power @ 8000 ft (max): 580 nm / 4.8 hrs ▶ 60% Power @ 10000 ft (econ):
Range 687 nm / 6.6 hrs ▶ Rate Of Climb At Sea Level: 720 fpm ▶ Service Ceiling: 13,500 ft
TAKEOFF
▶ Ground Roll: 945 ft ▶ Total Distance Over 50 ft Obstacle: 1685 ft
LANDING
▶ Ground Roll : 550 ft ▶ Total Distance Over 50 ft Obstacle : 1295 ft
STALL SPEED
▶ Flaps Up, Power Off: 51 kcas ▶ Flaps Down, Power Off: 47 kcas
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SPECIFICATIONS
GENERAL
ENGINE
▶ Textron Lycoming, IO-360-L2A, Normally
aspirated, direct drive, air-cooled, horizon­tally opposed, fuel injected, four cylinder engine with 360 cu. in. displacement.
▶ Horsepower Rating and Engine Speed:
 160 rated BHP at 2,400 RPM.
PROPELLER
▶ Two blade, Fixed pitch, 75” 70° pitch Mc-
Cauley, Model Number 1C235/LFA7570.
FUEL
Fuel Capacity:
 Total Capacity: 56.0 U.S. gallons.  Total Usable: 53.0 U.S. gallons.  Total Capacity Each Tank: 28.0 U.S. gallons.  Total Usable Each Tank: 26.5 U.S. gallons.
▶ 100LL Grade Aviation Fuel
OIL
Oil Capacity:
 Sump: 8 U.S. Quarts  Total: 9 U.S. Quarts
▶ Recommended Viscosity
for Temperature Range:
 Above 16°C (60°F) 50 (w100)  -18°C (0°F) to 32°C (90°F) 20W-50  All Temperatures 15W-50
MAX WEIGHTS
▶ Max Takeoff Weight: 2450 lbs. ▶ Max Baggage Area Weight: 120lbs
STANDARD AIRPLANE WEIGHTS
▶ Standard Empty Weight: 1639 lbs. ▶ Maximum Useful Load (total fuel, pas-
sengers, and baggage): 818 lbs
LIMITATIONS
VNE (Never Exceed)
Do not exceed 163 kias in any speed operation.
VNO (Maximum Structural)
Do not exceed 129 kias except in smooth air, and then only with caution.
VA (Maneuvering Speed)
Do not make full or abrupt control movements above this speed.
 2,450 lbs.: 99 kias  2,000 lbs.: 92 kias  1,600 lbs.: 82 kias
VFE (Maximum Flap Speed)
Do not exceed this speed with flaps
 10° Flaps: 110 kias  10° to 30° Flaps: 85 kias
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AIRSPEED INDICATOR MARKINGS
WHITE ARC (flaps extended)
 Full Flap Operating Range (33 – 85 kias)  Lowest speed at maximum weight
with full flaps is 33 kias
 Maximum speed permissible with flaps
extended beyond 10° is 85 kias
GREEN ARC (flaps retracted)
 Normal Operating Range (44 – 129 kias)  Lowest speed at maximum weight with is 44 kias  Maximum structural cruising speed is 129 kias
YELLOW ARC
 Operations must be conducted with cau-
tion and only in smooth air (129-163 kias)
RED LINE
 Maximum speed for all operations is 163 kias
POWERPLANT LIMITATIONS
CENTER OF GRAVITY LIMITS
Center of Gravity Range:
 Forward: 35.0 inches a of datum at 1950
lbs. or less, with straight line variation to
40.0 inches a of datum at 2450 lbs.  A: 47.3 inches a of datum at all weights.  Reference Datum: Lower por-
tion of front face of firewall.
MANEUVER LIMITS
Maneuvers And Recommended Entry Speed*
 Chandelles 105 kias  Lazy Eights 105 kias  Steep Turns 95 kias  Stalls (Except Whip Stalls) Slow Deceleration
* Abrupt use of the controls is prohibited above 99 kias.
Aerobatics that may impose high loads should not be attempted. The important thing to bear in mind in flight maneuvers is that the airplane is clean in aerodynamic design and will build up speed quickly with the nose down. Proper speed control is an essential requirement for execution of any maneuver, and care should always be exercised to avoid excessive speed which in turn can impose excessive loads. In the execution of all maneu­vers, avoid abrupt use of controls.
FLIGHT LOAD FACTOR LIMITS
Flight Load Factors
(Maximum Takeoff Weight - 2450 lbs.):
 *Flaps Up +3.8g, -1.52g  *Flaps Down +3.0g
*The design load factors are 150% of the above, and in
all cases, the structure meets or exceeds design loads.
▶ Flap Limitations
 Approved Takeo Range: 0° to 10°  Approved Landing Range: 0° to 30°
▶ Maximum Engine Speed: 2400 RPM.
NOTE: The static RPM range (full throttle when
stopped at sea level) is 2,065 – 2,165 RPM. ▶ Maximum Oil Temperature: 245°F (118°C). ▶ Oil Pressure, Minimum: 20 PSI, Maximum: 115 PSI.
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NORMAL OPERATIONS

Airspeeds for normal operation of the C172.
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ERE IS A brief sum­mury of the airspeeds required for normal op­erations of the Accu-Sim
H
AIRSPEEDS FOR NORMAL OPERATION
Unless otherwise noted, the following speeds are based on a maximum weight of 2450 pounds and may be used for any lesser weight.
TAKEOFF
▶ Normal Climb Out: 70-80 kias ▶ Short Field Takeoff, Flaps 10°,
Speed at 50 Feet: 57 kias
ENROUTE CLIMB, FLAPS UP
NORMAL
Sea Level: 75-85 kias 10,000 Feet: 70-80 kias
BEST RATE-OF-CLIMB
Sea Level: 79 kias 10,000 Feet: 71 kias
BEST ANGLE-OF-CLIMB
Sea Level: 60 kias 10,000 Feet: 65 kias
C172 aircra.
LANDING APPROACH
▶ Normal Approach, Flaps Up: 65-75 kias ▶ Normal Approach, Flaps 30°: 60-70 kias ▶ Short Field Approach, Flaps 30°: 62 kias
BALKED LANDING
▶ Maximum Power, Flaps 20°: 55 kias
MAXIMUM RECOMMENDED TURBULENT AIR PENETRATION SPEED
▶ 2450 lbs: 99 kias ▶ 2000 lbs: 92 kias ▶ 1600 lbs: 82 kias
MAXIMUM DEMONSTRATED CROSSWIND VELOCITY
▶ Takeoff or Landing: 15 kts
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CHECKLISTS

Normal operations checklists and procedures for the Accu-Sim C172 Trainer.
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CABIN
1. Pitot Tube Cover — REMOVE. Check for pitot blockage.
2. Pilot’s Operating Handbook — AVAILABLE IN THE AIRPLANE
3. Airplane Weight and Balance — CHECKED
4. Parking Brake — SET
5. Control Wheel Lock — REMOVE
6. Ignition Switch — OFF
7. Avionics Master Switch — OFF
WARNING: When turning on the master switch, using an external power
source, or pulling the propeller through by hand, treat the propeller as if the ignition switch were on. Do not stand, nor allow anyone else to stand, within the arc of the propeller, since a loose or broken wire or a component malfunction could cause the propeller to rotate.
8. Master Switch — ON
9. Fuel Quantity Indicators — CHECK QUANTITY AND ENSURE LOW
FUEL ANNUNCIATORS (L LOW FUEL R) ARE EXTINGUISHED
10. Avionics Master Switch — ON
11. Avionics Cooling Fan — CHECK AUDIBLY FOR OPERATION
12. Avionics Master Switch — OFF
13. Static Pressure Alternate Source Valve — OFF
14. Annunciator Panel Switch — PLACE AND HOLD IN TST POSITION and ensure all annunciators illuminate
NOTE: When Master Switch is turned ON, some annunciators will flash for
approximately 10 seconds before illuminating steadily. When panel TST switch is toggled up and held in position, all remaining lights will flash un­til the switch is released.
15. Fuel Selector Valve — BOTH
16. Fuel Shuto Valve — ON (Push Full In)
17. Flaps — EXTEND
18. Pitot Heat — ON (Carefully check that pitot tube
is warm to the touch within 30 seconds)
19. Pitot Heat — OFF
20. Master Switch — OFF
21. Elevator Trim — SET for takeo
22. Baggage Door — CHECK, lock with key
23. Autopilot Static Source Opening (if installed) — CHECK for blockage
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CHECKLISTS
BEFORE STARTING ENGINE
1. Preflight Inspection — COMPLETE
2. Passenger Briefing — COMPLETE
3. Seats and Seat Belts — ADJUST and LOCK Ensure inertia reel locking.
4. Brakes — TEST and SET
5. Circuit Breakers — CHECK IN
6. Electrical Equipment — OFF
NOTE: the avionics master switch must be o during engine start to prevent
possible damage to avionics.
7. Avionics Master Switch — OFF
8. Fuel Selector Valve — BOTH
9. Fuel Shuto Valve — ON (push full in)
10. Avionics Circuit Breakers — CHECK IN
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STARTING ENGINE (WITH BATTERY)
1. Throttle — OPEN  INCH
2. Mixture — IDLE CUTOFF
3. Propeller Area — CLEAR
4. Master Switch — ON
5. Flashing Beacon — ON
NOTE: If engine is warm, omit priming procedure of steps 6, 7, and 8 below.
6. Auxiliary Fuel Pump Switch — ON
7. Mixture — SET to FULL RICH (full forward) until stable fuel flow is indicated (usually 3 to 5 seconds), then set to IDLE CUTOFF (full a) position.
8. Auxiliary Fuel Pump — OFF
9. Ignition Switch — START (release when engine starts)
10. Mixture — ADVANCE smoothly to RICH when engine starts.
NOTE: If engine floods (engine has been primed too much), turn o auxiliary fuel pump, set mixture to idle cuto, open throttle 1/2 to full, and motor (crank) engine. When engine starts, set mixture to full rich and close throttle promptly.
11. Oil Pressure — CHECK
12. Navigation Lights — ON as required
13. Electrical System – CHECK FOR PROPER OPERATION:
a. Master Switch — OFF
b. Taxi and Landing Light Switches – ON (provides an initial electrical load on the system).
c. Engine RPM — REDUCE to idle (Minimum alternator output occurs at idle)
d. Master Switch — ON (taxi and landing lights on)
NOTE: (The ammeter should indicate in the negative direction, showing that the alternator out­put is below the load requirements, but the battery is supplying current to the system.)
e. Engine RPM — INCREASE to approximately 1500 RPM (as engine RPM increases,
alternator output should increase to meet the system load requirements)
f. Ammeter and Low Voltage Annunciator – CHECK (the ammeter should
indicate in the positive direction, showing that the alternator is supplying current and the Low Voltage Annunciator (VOLTS) should not be lighted)
NOTE: If the indications, as noted in Step “d” and Step “f”, are not observed, the electrical system is not functioning properly. Corrective maintenance must be performed to provide for proper electrical system operation before flight.
14. Avionics Master Switch — ON
15. Radios – ON
16. Flaps — RETRACT
17. Mixture — LEAN for ground operations.
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CHECKLISTS
BEFORE TAKEOFF
1. Parking Brake — SET
2. Passenger Seat Backs — MOST UPRIGHT POSITION
3. Seats and Seat Belts — CHECK SECURE
4. Cabin Doors — CLOSED and LOCKED
5. Flight Controls — FREE and CORRECT
6. Flight Instruments — CHECK and SET
7. Fuel Quantity — CHECK
8. Mixture — RICH
9. Fuel Selector Valve — RECHECK BOTH
10. Throttle — 1800 RPM
a. Magnetos — CHECK (RPM drop
should not exceed 150 RPM on either magneto or 50 RPM dierential between magnetos).
b. Vacuum Gage — CHECK
c. Engine Instruments and
Ammeter — CHECK
11. Annunciator Panel — Ensure no
annunciators are illuminated
12. Throttle — CHECK IDLE
13. Throttle — 1000 RPM or LESS
14. Throttle Friction Lock — ADJUST
15. Strobe Lights — AS DESIRED
16. Radios and Avionics — SET
17. NAV/GPS Switch (if installed) — SET
18. Autopilot (if installed) — OFF
19. Elevator Trim — SET for takeo
20. Wing Flaps — SET for takeo (0°-10°)
21. Brakes – RELEASE
NORMAL TAKEOFF
1. Wing Flaps — 0°-10°
2. Throttle — FULL OPEN
3. Mixture — RICH (above 3000 feet, LEAN to obtain maximum RPM)
4. Elevator Control — LIFT NOSE WHEEL (at 55 kias)
5. Climb Speed — 70-80 KIAS
6. Wing Flaps — RETRACT
SHORT FIELD TAKEOFF
1. Wing Flaps — 10°
2. Brakes — APPLY
3. Throttle — FULL OPEN
4. Mixture — RICH (above 3000 feet, LEAN to obtain maximum RPM)
5. Brakes — RELEASE
6. Elevator Control — SLIGHTLY TAIL LOW
7. Climb Speed — 57 KIAS (until
all obstacles are cleared)
8. Wing Flaps — RETRACT slowly aer reaching 60 kias
ENROUTE CLIMB
1. Airspeed — 70-85 KIAS
NOTE: If a maximum performance climb is necessary, use speeds shown in the Rate Of Climb chart later in this manual.
2. Throttle — FULL OPEN
3. Mixture — RICH (above 3000 feet, LEAN to obtain maximumRPM)
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CRUISE
SHORT FIELD LANDING
1. Power — 2000-2400 RPM (No more than 80% is recommended)
2. Elevator Trim — ADJUST
3. Mixture — LEAN
DESCENT
1. Power — AS DESIRED
2. Mixture — ADJUST for smooth operation
3. Altimeter — SET
4. NAV/GPS Switch — SET
5. Fuel Selector Valve — BOTH
6. Wing Flaps — AS DESIRED (0° - 10°
below 110 kias, 10° - 30° below 85 kias)
BEFORE LANDING
1. Pilot and Passenger Seat Backs — MOST UPRIGHT POSITION
2. Seats and Seat Belts — SECURED AND LOCKED
3. Fuel Selector Valve — BOTH
4. Mixture — RICH
5. Landing/Taxi Lights — ON
6. Autopilot (if installed) — OFF
NORMAL LANDING
1. Airspeed — 65-75 KIAS (flaps UP)
2. Wing Flaps — AS DESIRED (0°-10°
below 110 kias, 10°-30° below 85 kias)
3. Airspeed — 60-70 KIAS (flaps DOWN)
4. Touchdown — MAIN WHEELS FIRST
5. Landing Roll — LOWER NOSE WHEEL GENTLY
6. Braking — MINIMUM REQUIRED
1. Airspeed — 65-75 KIAS (flaps UP)
2. Wing Flaps — FULL DOWN (30°)
3. Airspeed — 62 KIAS (until flare)
4. Power — REDUCE to idle
aer clearing obstacle
5. Touchdown — MAIN WHEELS FIRST
6. Brakes — APPLY HEAVILY
7. Wing Flaps — RETRACT
BALKED LANDING
1. Throttle — FULL OPEN
2. Wing Flaps — RETRACT TO 20°
3. Climb Speed — 55 KIAS
4. Wing Flaps — 10° (until obstacles
are cleared), RETRACT (aer reaching a safe altitude and 60 kias)
AFTER LANDING
1. Wing Flaps — UP
SECURING AIRPLANE
1. Parking Brake — SET
2. Electrical Equipment, Autopilot (if installed) — OFF
3. Avionics Master Switch — OFF
4. Mixture — IDLE CUT OFF (pulled full out)
5. Ignition Switch — OFF
6. Master Switch — OFF
7. Control Lock — INSTALL
8. Fuel Selector Valve – LEFT or RIGHT to prevent cross feeding
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PROCEDURES EXPLAINED

A more in-depth look at the normal operation procedures.
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HIS SECTION WILL give you a more detailed look at the normal operating procedures covered by the
T
checklists.
STARTING ENGINE
The Lycoming IO-360 engine in your Cessna 172R is fuel injected, and priming is done using both the electric fuel pump and the mixture control. Turn the electric fuel pump on (pumps fuel through the lines and builds up pressure). Carefully watch your fuel flow gauges and push the mixture control in. You will hear a slight dierence in the fuel pump as the primer starts to flow and the fuel flow gauge will rise just slightly. Once you see an indication, wait 3-5 seconds, then pull back on the mixture control and turn o the electric fuel pump. The engine is now primed.
To start the engine, in the real aircra make sure you clear the area with a loud “CLEAR PROP”, wait a few seconds and scan the area. Crack the throttle then turn the starter key to the START posi­tion. Once the engine begins to catch, push the mixture control IN and adjust the throttle to maintain about 1,000 RPM.
When the engine starts, smooth­ly advance the mixture control to full rich and retard the throttle to desired idle speed. If the engine is
under primed (most likely in cold weather with a cold engine) it will not start at all, and additional prim­ing will be necessary. Aer starting, if the oil pressure gauge does not begin to indicate pressure within 30 seconds in the summer time and approximately one minute in very cold weather, stop the engine and investigate. Lack of oil pressure can cause serious engine damage.
NOTE: Additional details concerning cold weather starting and operation may be found under COLD WEATHER OPERATION paragraphs in this sec tion.
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RECOMMENDED STARTER DUTY CYCLE
Crank the starter for 10 seconds followed by a 20 second cool down period. This cycle can be repeated two additional times, followed by a ten minute cool down period before resuming cranking. Aer cool down, crank the starter again, three cycles of 10 seconds followed by 20 seconds of cool down. If the engine still fails to start, an inves­tigation to determine the cause should be initiated.
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PROCEDURES EXPLAINED
LEANING FOR GROUND OPERATIONS
▶ For all ground operations,
after starting the engine and when the engine is running smoothly:
a. Set the throttle
to 1200 RPM.
b. Lean the mixture for
maximum RPM.
c. Set the throttle to an RPM
appropriate for ground operations (800 to 1000 RPM recommended)
NOTE: If ground operation will be re­quired aer the BEFORE TAKEOFF checklist is completed, lean the mix ture again (as described above) until ready for the TAKEOFF checklist.
TAXIING
When taxiing, it is important that speed and use of brakes be held to a minimum and that all controls be utilized to maintain directional control and balance. Taxiing over loose gravel or cinders should be done at low engine speed to avoid abrasion and stone damage to the propeller tips.
BEFORE TAKEOFF
WARM UP
If the engine idles (approximately 600 RPM) and accelerates smoothly, the airplane is ready for takeo. Since the engine is closely cowled for eicient in-flight engine cool­ing, precautions should be taken to avoid overheating during pro­longed engine operation on the ground. Also, long periods of idling may cause fouled spark plugs.
MAGNETO CHECK
The magneto check should be made at 1800 RPM as follows. Move ignition switch first to R po sition and note RPM. Next move switch back to BOTH to clear the other set of plugs. Then move switch to the L position, note RPM and return the switch to the BOTH position. RPM drop should not ex ceed 150 RPM on either magneto or show greater than 50 RPM dif
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ferential between magnetos. If there is a doubt concerning opera tion of the ignition system, RPM checks at higher engine speeds will usually confirm whether a deficiency exists. An absence of RPM drop may be an indication of faulty grounding of one side of the ignition system or should be cause for suspicion that the mag neto timing is set in advance of the setting specified.
ALTERNATOR CHECK
Prior to flights where verification of proper alternator and alterna­tor control unit operation is essen­tial (such as night or instrument flights), a positive verification can be made by loading the electrical system momentarily (3 to 5 sec­onds) with the landing light or by operating the wing flaps during the engine runup (1800 RPM). The am­meter will remain within a needle width of its initial reading if the al­ternator and alternator control unit are operating properly.
LANDING LIGHTS
If landing lights are to be used to en­hance the visibility of the airplane in the traic pattern or enroute, it is recommended that only the taxi light be used. This will extend the service life of the landing light ap­preciably.
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TAKEOFF
POWER CHECK
It is important to check full throttle engine operation early in the take­o roll. Any sign of rough engine op­eration or sluggish engine accelera­tion is good cause for discontinuing the takeo. If this occurs, you are justified in making a thorough full throttle static runup before another takeo is attempted. The engine should run smoothly and turn ap­proximately 2100 RPM with mixture leaned to provide maximum RPM. Prior to takeo from fields above 3000 feet elevation, the mixture should be leaned to give maximum RPM in a full throttle, static runup. Aer full throttle is applied, adjust the throttle friction lock clockwise to prevent the throttle from creep­ing back from a maximum power position. Similar friction lock ad­justments should be made as re­quired in other flight conditions to maintain a fixed throttle setting.
WING FLAP SETTINGS
Normal takeos are accomplished with wing flaps 0°-10°. Using 10° wing flaps reduces the ground roll and total distance over an obsta­cle by approximately 10 percent. Flap deflections greater than 10° are not approved for takeo. If 10° wing flaps are used for takeo, they should be le down until all obsta-
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cles are cleared and a safe flap re­traction speed of 60 kias is reached. On a short field, 10° wing flaps and an obstacle clearance speed of 57 kias should be used.
So or rough field takeos are performed with 10° flaps by liing the airplane o the ground as soon as practical in a slightly tail low atti­tude. If no obstacles are ahead, the airplane should be leveled o im­mediately to accelerate to a higher climb speed. When departing a so field with an a C.G. loading, the elevator trim should be adjusted towards the nose down direction to give comfortable control wheel forces during the initial climb.
CROSSWIND TAKEOFF
Takeos into strong crosswind con­ditions normally are performed with the minimum flap setting necessary for the field length, to minimize the dri angle immediately aer take­o. With the ailerons partially de­flected into the wind, the airplane is accelerated to a speed slightly higher than normal, then pulled o briskly to prevent possible settling back to the runway while driing. When clear of the ground, make a coordinated turn into the wind to correct for dri.
ENROUTE CLIMB
Enroute climbs are performed with flaps up and full throttle and at speeds 5 to 10 kias higher than best rate-of-climb speeds for the best combination of performance, visibility and engine cooling. The mixture should be full rich below 3000 feet and may be leaned above 3000 feet for smoother operation or to obtain maximum RPM. For maximum rate of climb, use the best rate-of-climb speeds shown in the Rate of Climb chart later in this manual. If an obstruction dictates the use of a steep climb angle, the best angle-of-climb speed should be used with flaps up and maximum power. Climbs at speeds lower than the best rate-of-climb speed should be of short duration to improve en­gine cooling.
CRUISE
Normal cruise is performed be- tween 60% and 80% power. The engine RPM and corresponding fuel consumption for various altitudes can be determined by using the cruise charts later in this manual.
The Cruise Performance charts provide the pilot with detailed infor mation concerning the cruise perfor- mance of the Model 172R in still air. Power and altitude, as well as winds alo, have a strong influence on the time and fuel needed to complete any flight. The Cruise Performance Table illustrates the true airspeed and nau tical miles per gallon during cruise for various altitudes and percent powers, and is based on standard conditions and zero wind. This table should be used as a guide, along with the avail able winds alo information, to deter­mine the most favorable altitude and power setting for a given trip. The se lection of cruise altitude on the basis of the most favorable wind conditions and the use of low power settings are significant factors that should be con sidered on every trip to reduce fuel consumption. In addition to power settings, proper leaning techniques also contribute to greater range and are figured into cruise performance tables. To achieve the recommended lean mixture fuel consumption, the mixture should be leaned using the exhaust gas temperature (EGT) indi cator as noted.
CRUISE PERFORMANCE TABLE
ALTITUDE
Sea Level 113 12.3 108 13.4 100 14.5
4000 feet 117 12.8 111 13.9 103 14.9
8000 feet 122 13.3 115 14.3 105 15.3
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LEANING USING THE EGT INDICATOR
At or below 80% power in level
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80% POWER 70% POWER 60% POWER
KTAS NMPG KTAS NMPG KTAS NMPG
RECOMMENDED LEAN PER EGT TABLE
MIXTURE
DESCRIPTION
Recommended Lean 50° Rich of Peak EGT
Best Economy Peak EGT
cruise flight, the exhaust gas tem­perature (EGT) indicator is used to lean the fuel-air mixture for best performance or economy. The Cruise Performance charts are based on the EGT to adjust the mix­ture to Recommended Lean per EGT Table below.
Use the mixture control to slowly lean, from full rich or maximum RPM mixture, while monitoring the EGT indicator. As the EGT indication be­gins to increase, continue to slowly lean the mixture until an EGT indi­cation decrease is just detectable.
XHAUST GAS
TEMPERATURE
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PROCEDURES EXPLAINED
Reverse the adjustment slowly in the rich direction until an EGT indi­cation decrease is again just detect­able, then set the EGT index pointer to match the peak indication. The mixture may be leaned slightly to return to peak EGT or may be further richened to Recommended Lean mixture as desired. Continuous op-
eration at mixture settings lean of peak EGT is prohibited. Any change
in altitude or throttle position will require that peak EGT be redeter­mined and the desired mixture be reset. Under some conditions, en­gine roughness may occur at peak EGT. In this case, operate at Recom­mended Lean mixture.
As noted in EGT Table, operation at peak EGT provides the best fuel economy. Operation at peak EGT results in approximately 4% greater range and approximately a 3 knot decrease in airspeed from the fig­ures shown in the Performance sec­tion of this handbook. Recommend­ed Lean mixture provides best level cruise performance(generally close to “best power” or maximum RPM).
NOTE: The EGT indicator requires several seconds to respond to mixture adjustments and changes in exhaust gas temperature. More rapid changes in EGT indication are neither neces sary nor desirable. Determining peak EGT and setting the desired mixture should take approximately one min ute when the adjustments are made suiciently slowly and accurately.
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TAKEOFF checklist is com-
plete re-lean the mixture as described above until ready for the TAKEOFF checklist.
2. Lean the mixture for maxi­mum RPM during full throttle climbs above 3000 feet. The mixture may remain leaned (maximum RPM at full throttle) for practicing maneuvers such as stalls and slow flight.
3. Lean the mixture for maximum RPM during all operations at any altitude, including those below 3000 feet, when using 80% or less power.
NOTE: When cruising or maneuver­ing at 80% or less power, the mixture may be further leaned until the EGT indicator needle peaks and is then enrichened 50°F. This is especially applicable to cross-country training flights, but should be practiced dur ing transition flight to and from the practice area as well. Using the above recommended procedures can provide fuel savings in excess of 5% when com
-
-
pared to typical training operations at full rich mixture. In addition, the above procedures will minimize spark plug fouling since the reduction in fuel consumption results in a proportional reduction in tetraethyl lead passing through the engine.
STALLS
The stall characteristics are con­ventional and aural warning is pro­vided by a stall warning horn which sounds between 5 and 10 kias above the stall in all configurations.
LANDING
NORMAL LANDING
Normal landing approaches can be made with power on or power o with any flap setting desired. Sur­face winds and air turbulence are usually the primary factors in de­termining the most comfortable ap­proach speeds. Steep slips should be avoided with flap settings great­er than 20° due to a slight tendency for the elevator to oscillate under certain combinations of airspeed, sideslip angle, and center of gravity loadings.
FUEL SAVINGS PROCEDURES FOR FLIGHT TRAINING OPERATIONS
For best fuel economy during flight training operations, the following procedures are recommended.
1. After engine start and for all ground operations, set the throttle to 1200 RPM and lean the mixture for maxi­mum RPM. Leave the mixture at this setting until begin­ning the BEFORE TAKEOFF checklist. After the BEFORE
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Actual touchdown should be
made with power o and on the main wheels first to reduce the landing speed and subsequent need for braking in the landing roll. The nose wheel is lowered to the runway gently aer the speed has diminished to avoid unnecessary nose gear loads. This procedure is especially important in rough or so field landings.
SHORT FIELD LANDING
For a short field landing in smooth air conditions, make an approach at 62 kias with 30° flaps using enough power to control the glide path. (Slightly higher approach speeds should be used under turbulent air conditions.) Aer all approach ob­stacles are cleared, progressively reduce power and maintain the ap­proach speed by lowering the nose of the airplane. Touchdown should be made with power o and on the main wheels first. Immediately aer touchdown, lower the nose wheel and apply heavy braking as required. For maximum brake eec­tiveness, retract the flaps, hold the
control wheel full back, and apply maximum brake pressure without sliding the tires.
CROSSWIND LANDING
When landing in a strong cross­wind, use the minimum flap setting required for the field length. If flap settings greater than 20° are used in sideslips with full rudder deflec­tion, some elevator oscillation may be felt at normal approach speeds. However, this does not aect con­trol of the airplane. Although the crab or combination method of dri correction may be used, the wing low method gives the best control. Aer touchdown, hold a straight course with the steerable nose wheel and occasional braking if necessary.
The maximum allowable cross­wind velocity is dependent upon pilot capability as well as airplane limitations. Operation in direct crosswinds of 15 kts has been dem­onstrated.
BALKED LANDING
In a balked landing (go-around)
climb, reduce the flap setting to 20° immediately aer full power is applied. If obstacles must be cleared during the go-around climb, reduce the wing flap set ting to 10° and maintain a safe airspeed until the obstacles are cleared. Above 3000 feet, lean the mixture to obtain maximum RPM. Aer clearing any obstacles, the flaps may be retracted as the air plane accelerates to the normal flaps up climb speed.
-
-
COLD WEATHER OPERATION
When air temperatures are below 20°F (-6°C), the use of an external preheater and an external power source are recommended whenever possible to obtain positive starting and to reduce wear and abuse to the engine and electrical system. Preheat will thaw the oil trapped in the oil cooler, which probably will be congealed prior to starting in ex­tremely cold temperatures.
HOT WEATHER OPERATION
Avoid prolonged engine operation on the ground.
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PERFORMANCE CHARTS
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What you need to know to plan your flights.
ERFORMANCE DATA CHARTS
on the following pages are presented so that you may know what to expect from
P
the airplane under various conditions, and also, to facilitate the planning of flights in detail and with reasonable accuracy. The data in the charts has been computed from ac­tual flight tests with the airplane and engine in good condition and approx­imating average piloting techniques.
It should be noted that performance information presented in the range and endurance profile charts al­lows for 45 minutes reserve fuel at the specified power setting. Fuel flow data for cruise is based on the recom­mended lean mixture setting at all altitudes. Some inde­terminate variables such as mixture leaning technique, fuel metering characteristics, engine and propeller con­dition, and air turbulence may account for variations of 10% or more in range and endurance. Therefore, it is im­portant to utilize all available information to estimate the fuel required for the particular flight and to flight plan in a conservative manner.
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PERFORMANCE CHARTS
STALL SPEEDS AT 2450 POUNDS
MOST REARWARD CENTER OF GRAVITY
FLAP
SETTING
UP 44 48 53 63
10° 35 38 42 50
30° 33 36 40 47
MOST FORWARD CENTER OF GRAVITY
FLAP
SETTING
UP 44 48 53 63
10° 37 40 44 53
30° 33 36 40 47
CONDITIONS
Power O
NOTES
1. Altitude loss during a stall recovery may be as much as 230 feet.
2. KIAS values are approximate.
3. Maximum demonstrated crosswind component is 15 kts (not a limitation).
ANGLE OF BANK
30° 45° 60°
ANGLE OF BANK
30° 45° 60°
SHORT FIELD TAKEOFF DISTANCE AT 2450 POUNDS
0°C 10°C 20°C 30°C 40°C
Pressure
Altitude
(.)
Sea Level 845 1510 910 1625 980 1745 1055 1875 1135 2015
1000 925 1660 1000 1790 1075 1925 1160 2070 1245 2220
2000 1015 1830 1095 1970 1185 2125 1275 2290 1365 2455
3000 1115 2020 1205 2185 1305 2360 1400 2540 1505 2730
4000 1230 2245 1330 2430 1435 2630 1545 2830 1655 3045
5000 1355 2500 1470 2715 1585 2945 1705 3175 1830 3430
6000 1500 2805 1625 3060 1750 3315 1880 3590 2020 3895
7000 1660 3170 1795 3470 1935 3770 2085 4105 2240 4485
8000 1840 3620 1995 3975 2150 4345 2315 4775 - - - - - -
CONDITIONS
Flaps 10° Full Throttle Prior to Brake Release Paved, level, dry runway Zero Wind Li O: 51 kias Speed at 50 : 57 kias
Ground
Roll (.)
Total . to Clear
50.
Obstacle
Ground
Roll (.)
NOTES
1. Short field technique as specified.
2. Prior to takeo from fields above 3000 feet elevation, the mixture should be leaned to give maximum RPM in a full throttle, static runup.
3. Decrease distances 10% for each 9 kts headwind. For operation with tail winds up to 10 kts, increase distances by 10% for each 2 kts.
4. For operation on dry, grass runway, increase distances by 15% of the ground roll” figure.
5. Where distance value has been deleted, climb performance is minimal.
Total . to Clear
50.
Obstacle
Ground
Roll (.)
Total . to Clear
50.
Obstacle
Ground
Roll (.)
Total . to Clear
50.
Obstacle
Ground
Roll (.)
Total . to Clear
Obstacle
50.
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MAXIMUM RATE-OF-CLIMB AT 2450 POUNDS
Pressure
Altitude
(.)
Sea Level 79 830 770 705 640
2000 77 720 655 595 535
4000 76 645 585 525 465
6000 74 530 475 415 360
8000 72 420 365 310 250
10,000 71 310 255 200 145
12,000 69 200 145 - - - - - -
CONDITIONS
Flaps Up Full Throttle
NOTE
Mixture leaned above 3000 feet for maximum RPM.
Climb Speed (KIAS)
RATE OF CLIMB (FPM)
-20°C 0°C 20°C 40°C
TIME, FUEL AND DISTANCE TO CLIMB AT 2450 POUNDS
Pressure
Altitude
(.)
Temp.
(°C)
Climb Speed (KIAS)
Rate of
Climb (FPM)
Sea Level 15 79 720 0 0.0 0
1000 13 78 670 1 0.4 2
2000 11 77 625 3 0.7 4
3000 9 76 575 5 1.2 6
4000 7 76 560 6 1.5 8
5000 5 75 515 8 1.8 11
6000 3 74 465 10 2.1 14
7000 1 73 415 13 2.5 17
8000 -1 72 365 15 3.0 21
9000 -3 72 315 18 3.4 25
10,000 -5 71 270 22 4.0 29
11,000 -7 70 220 26 4.6 35
12,000 -9 69 170 31 5.4 43
CONDITIONS
Flaps Up Full Throttle Standard Temperature
NOTES
1. Add 1.1 gallons of fuel for engine start, taxi and takeo allowance.
2. Mixture leaned above 3000 feet for maximum RPM.
3. Increase time, fuel and distance by 10% for each 10°C above standard temperature.
4. Distances shown are based on zero wind.
FROM SEA LEVEL
Time
(min.)
Fuel Used
(gal.)
Distance
(nm.)
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PERFORMANCE CHARTS
CRUISE PERFORMANCE
Pressure
Altitude
20°C BELOW STANDARD
(.)
RPM
2000 2250 - - - - - - - - - 79 115 9.0 74 114 8.5
2200 79 112 9.1 74 112 8.5 70 111 8.0
2100 69 107 7.9 65 106 7.5 65 105 7.1
2000 61 101 7.0 58 99 6.6 55 97 6.4
1900 54 94 6.2 51 91 5.9 50 89 5.8
4000 2300 - - - - - - - - - 79 117 9.1 75 117 8.6
2250 80 115 9.2 75 114 8.6 70 114 8.1
2200 75 112 8.6 70 111 8.1 66 110 7.6
2100 66 106 7.6 62 105 7.1 59 103 6.8
2000 58 100 6.7 55 98 6.4 53 95 6.2
1900 52 92 6.0 50 90 5.8 49 87 5.6
6000 2350 - - - - - - - - - 80 120 9.2 75 119 8.6
2300 80 117 9.2 75 117 8.6 71 116 8.1
2250 76 115 8.7 71 114 8.1 67 113 7.7
2200 71 112 8.1 67 111 7.7 64 109 7.3
2100 63 105 7.2 60 104 6.9 57 101 6.6
2000 56 98 6.4 53 96 6.2 52 93 6.0
TEMPERATURE
% BHP KTAS GPH % BHP KTAS GPH % BHP KTAS GPH
STANDARD
TEMPERATURE
20°C ABOVE STANDARD
TEMPERATURE
8000 2400 - - - - - - - - - 80 122 9.2 76 121 8.7
2350 81 120 9.3 76 119 8.7 71 118 8.2
2300 76 117 8.7 71 116 8.2 68 115 7.8
2200 68 111 7.7 64 110 7.3 61 107 7.0
2100 60 104 6.9 57 102 6.6 55 99 6.4
2000 54 96 6.2 52 94 6.0 51 91 5.9
10,000 2350 76 119 8.8 72 118 8.2 68 117 7.8
2300 72 116 8.3 68 115 7.8 65 113 7.4
2250 68 113 7.8 65 112 7.4 61 109 7.1
2200 65 110 7.4 61 108 7.0 59 105 6.7
2100 58 102 6.6 55 100 6.4 54 97 6.2
2000 52 94 6.1 51 91 5.9 50 88 5.8
12,000 2350 73 119 8.3 69 117 7.9 65 115 7.5
2300 69 115 7.9 65 113 7.5 62 111 7.1
2250 65 112 7.5 62 109 7.1 59 107 6.8
2200 62 108 7.1 59 105 6.8 57 103 6.6
2100 56 100 6.4 54 97 6.2 53 94 6.1
CONDITIONS
2450 Pounds Recommended Lean Mixture At All Altitudes.
NOTE
Performance is shown for an airplane equipped with speed fairings, which increase the cruise speeds by approximately two kias.
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RANGE PROFILE
45 MINUTES RESERVE
53 galLONS USABLE FUEL
ENDURANCE PROFILE
45 MINUTES RESERVE
53 galLONS USABLE FUEL
CONDITIONS
2450 Pounds Recommended Lean Mixture for Cruise At All Altitudes Standard Temperature Zero Wind
NOTES
1. This chart allows for the fuel used for engine start, taxi, takeo and climb, and the distance during climb.
2. Performance is shown for an airplane equipped with speed fairings, which increase the cruise speeds by approximately two kias.
CONDITIONS
2450 Pounds Recommended Lean Mixture for Cruise At All Altitudes Standard Temperature
NOTE
1. This chart allows for the fuel used for engine start, taxi, takeo and climb, and the time during climb.
SHORT FIELD LANDING DISTANCE AT 2450 POUNDS
0°C 10°C 20°C 30°C 40°C
Pressure
Altitude
(.)
Sea Level 525 1250 540 1280 560 1310 580 1340 600 1370
1000 545 1280 560 1310 580 1345 600 1375 620 1405
2000 565 1310 585 1345 605 1375 625 1410 645 1440
3000 585 1345 605 1380 625 1415 650 1445 670 1480
4000 605 1380 630 1415 650 1450 670 1485 695 1520
5000 630 1415 650 1455 675 1490 700 1525 720 1560
6000 655 1455 675 1490 700 1530 725 1565 750 1605
7000 680 1495 705 1535 730 1570 755 1610 775 1650
8000 705 1535 730 1575 755 1615 780 1655 810 1695
CONDITIONS
Flaps 30° Power O Maximum Braking Paved, level, dry runway Zero Wind Speed at 50 : 62 kias
Ground
Roll (.)
Total . to Clear
50.
Obstacle
Ground
Roll (.)
NOTES
1. Short field technique as specified in.
2. Decrease distances 10% for each 9 kts headwind. For operation with tail winds up to 10 kts, increase distances by 10% for each 2 kts.
3. For operation on dry, grass runway, increase distances by 45% of the “ground roll” figure.
4. If landing with flaps up, increase the approach speed by 7 kias and allow for 35% longer distances.
Total . to Clear
50.
Obstacle
Ground
Roll (.)
Total . to Clear
50.
Obstacle
Ground
Roll (.)
Total . to Clear
50.
Obstacle
Ground
Roll (.)
Total . to Clear
Obstacle
50.
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67

EMERGENCIES

Emergency procedures and checklists.
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HIS SECTION PROVIDES checklist and ex­plained procedures for coping with emer­gencies that may occur. Emergencies caused by airplane or engine malfunctions
T
are extremely rare if proper preflight in­spections and maintenance are practiced. En-route weather emergencies can be minimized or elimi­nated by careful flight planning and good judgment when unexpected weather is encountered. However, should an emergency arise, the basic guidelines de­scribed in this section should be considered and ap­plied as necessary to correct the problem.
AIRSPEEDS FOR EMERGENCY OPERATION
▶ Engine Failure After Takeoff
 Wing Flaps Up: 65 kias  Wing Flaps Down: 60 kias
▶ Maneuvering Speed
 2450 lbs: 99 kias  2100 lbs: 92 kias
 1600 lbs: 82 kias Maximum Glide: 65 kias Precautionary Landing With Engine Power: 60 kias
▶ Landing Without Engine Power
 Wing Flaps Up: 65 kias
 Wing Flaps Down: 60 kias
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EMERGENCIES
ENGINE FAILURE DURING TAKEOFF ROLL
1. Throttle — IDLE
2. Brakes — APPLY
3. Wing Flaps — RETRACT
4. Mixture — IDLE CUT OFF
5. Ignition Switch — OFF
6. Master Switch — OFF
ENGINE FAILURE IMMEDIATELY AFTER TAKEOFF
1. Airspeed — 65 kias (flaps UP)- 60 kias (flaps DOWN)
2. Mixture — IDLE CUT OFF
3. Fuel Shuto Valve — OFF (Pull Full Out)
4. Ignition Switch — OFF
5. Wing Flaps — AS REQUIRED
6. Master Switch — OFF
7. Cabin Door — UNLATCH
8. Land — STRAIGHT AHEAD
ENGINE FAILURE DURING FLIGHT (RESTART PROCEDURES)
1. Airspeed — 65 KIAS
2. Fuel Shuto Valve — ON (push full in)
3. Fuel Selector Valve — BOTH
4. Auxiliary Fuel Pump Switch — ON
5. Mixture — RICH (if restart
has not occurred)
6. Ignition Switch — BOTH (or START if propeller is stopped)
NOTE: If the propeller is windmilling, the engine will restart automatically within a few seconds. If the propeller has stopped (possible at low speeds), turn the ignition switch to START, ad­vance the throttle slowly from idle and lean the mixture from full rich as re­quired for smooth operation.
7. Auxiliary Fuel Pump Switch — OFF
NOTE: If the fuel flow indicator im­mediately drops to zero (indicating an engine-driven fuel pump failure), return the Auxiliary Fuel Pump Switch to the ON position.
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EMERGENCY LANDING
PRECAUTIONARY LANDING
WITHOUT ENGINE POWER
1. Passenger Seat Backs — MOST
UPRIGHT POSITION
2. Seats and Seat Belts — SECURE
3. Airspeed — 65 KIAS (flaps UP) - 60 kias (flaps DOWN)
4. Mixture — IDLE CUT OFF
5. Fuel Shuto Valve — OFF (Pull Full Out)
6. Ignition Switch — OFF
7. Wing Flaps — AS REQUIRED
(30° recommended)
8. Master Switch — OFF (when landing is assured)
9. Doors — UNLATCH PRIOR TO TOUCHDOWN
10. Touchdown — SLIGHTLY TAIL LOW
11. Brakes — APPLY HEAVILY
WITH ENGINE POWER
1. Passenger Seat Backs — MOST
UPRIGHT POSITION
2. Seats and Seat Belts — SECURE
3. Airspeed — 60 KIAS
4. Wing Flaps — 20°
5. Selected Field — FLY OVER, noting
terrain and obstructions, then retract flaps upon reaching a safe altitude and airspeed
6. Avionics Master Switch and Electrical Switches — OFF
7. Wing Flaps — 30° (on final approach)
8. Airspeed — 60 KIAS
9. Master Switch — OFF
10. Doors — UNLATCH PRIOR TO TOUCHDOWN
11. Touchdown — SLIGHTLY TAIL LOW
12. Ignition Switch — OFF
13. Mixture — IDLE CUTOFF
14. Brakes — APPLY HEAVILY
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EMERGENCIES
ENGINE FIRE DURING START ON GROUND
1. Ignition Switch — START, Continue Cranking to get a start which would suck the flames and accumulated fuel into the engine
If engine starts:
2. Power — 1700 RPM for a few minutes
3. Engine — SHUTDOWN and inspect for damage
If engine fails to start:
4. Throttle — FULL OPEN
5. Mixture — IDLE CUT OFF
6. Cranking — CONTINUE
7. Fuel Shuto Valve — OFF (Pull Full Out)
8. Auxiliary Fuel Pump — OFF
9. Fire Extinguisher — OBTAIN (have ground
attendants obtain if not installed)
10. Engine — SECURE
a. Master Switch — OFF
b. Ignition Switch — OFF
11. Parking Brake — RELEASE
12. Airplane — EVACUATE
13. Fire — EXTINGUISH using fire extinguisher, wool blanket, or dirt
14. Fire Damage — INSPECT, repair damage or replace damaged
components or wiring before conducting another flight
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ENGINE FIRE IN FLIGHT
1. Mixture — IDLE CUT OFF
2. Fuel Shuto Valve — OFF (Pull Full Out)
3. Auxiliary Fuel Pump Switch — OFF
4. Master Switch — OFF
5. Cabin Heat and Air — OFF (except overhead vents)
6. Airspeed — 100 KIAS (If fire is not extinguished, increase
glide speed to find an airspeed - within airspeed limitations
- which will provide an incombustible mixture)
7. Forced Landing — EXECUTE (as described in Emergency Landing Without Engine Power)
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AMMETER SHOWS EXCESSIVE RATE OF CHARGE (FULL SCALE DEFLECTION)
1. Alternator — OFF
2. Nonessential Electrical Equipment — OFF
3. Flight — TERMINATE as soon as practical
LOW VOLTAGE ANNUNCIATOR (VOLTS) ILLUMINATES DURING FLIGHT (AMMETER INDICATES DISCHARGE)
NOTE: Illumination of “VOLTS” on the annunciator panel may oc­cur during low RPM conditions with an electrical load on the system such as during a low RPM taxi. Under these conditions, the annun­ciator will go out at higher RPM. The master switch need not be recy­cled since an overvoltage condition has not occurred to deactivate the alternator system.
1. Avionics Master Switch — OFF
2. Alternator Circuit Breaker (ALT FLD) — CHECK IN
3. Master Switch — OFF (both sides)
4. Master Switch — ON
5. Low Voltage Annunciator (VOLTS) — CHECK OFF
6. Avionics Master Switch — ON
If low voltage annunciator (VOLTS) illuminates again:
7. Alternator-- OFF
8. Nonessential Radio and Electrical Equipment — OFF
9. Flight — TERMINATE as soon as practical
LEFT VACUUM (L VAC) ANNUNCIATOR OR RIGHT VACUUM (VAC R) ANNUNCIATOR ILLUMINATES.
NOTE: If vacuum is not within normal operating limits, a failure has occurred in the vacuum system and partial panel procedures may be required for continued flight.
1. Vacuum Gage — CHECK to ensure vacuum within normal operating limits.
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73

EMERGENCIES EXPLAINED

A more detailed look at the emergency procedures.
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HE FOLLOWING AMPLIFIED
Emergency Procedures elaborate upon informa­tion contained in the Emer-
T
gency Procedures Check­lists portion of this section. These procedures also include information not readily adaptable to a checklist format, and material to which a pilot could not be expected to refer in res­olution of a specific emergency. This information should be reviewed in detail prior to flying the airplane, as well as reviewed on a regular basis to keep pilot’s knowledge of proce­dures fresh.
ENGINE FAILURE
If an engine failure occurs during the takeo roll, the most important thing to do is stop the airplane on the remaining runway. Those extra items on the checklist will provide added safety aer a failure of this type. Prompt lowering of the nose to maintain airspeed and establish a glide attitude is the first response to an engine failure aer takeo. In most cases, the landing should be planned straight ahead with only small changes in direction to avoid obstructions. Altitude and airspeed are seldom suicient to execute a 180° gliding turn necessary to re-
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turn to the runway. The checklist procedures assume that adequate time exists to secure the fuel and ig­nition systems prior to touchdown. Aer an engine failure in flight, the most important course of action is to continue flying the airplane. Best glide speed should be established as quickly as possible. While glid­ing toward a suitable landing area, an eort should be made to identify the cause of the failure. If time per­mits, an engine restart should be at­tempted as shown in the checklist. If the engine cannot be restarted, a forced landing without power must be completed.
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EMERGENCIES EXPLAINED
FORCED LANDINGS
If all attempts to restart the engine fail and a forced landing is immi­nent, select a suitable field and pre­pare for the landing as discussed under the Emergency Landing With­out Engine Power checklist. Trans­mit Mayday message on 121.5 MHz giving location and intentions and squawk 7700. Before attempting an “o airport” landing with engine power available, one should fly over the landing area at a safe but low al­titude to inspect the terrain for ob­structions and surface conditions, proceeding as discussed under the Precautionary Landing With Engine Power checklist. Prepare for ditch­ing by securing or jettisoning heavy objects located in the baggage area and collect folded coats for protec­tion of occupants’ face at touch­down. Transmit Mayday message on 121.5 MHz giving location and in­tentions and squawk 7700. Avoid a landing flare because of diiculty in judging height over a water surface. The checklist assumes the avail­ability of power to make a precau­tionary water landing. If power is not available, use of the airspeeds noted with minimum flap exten­sion will provide a more favorable attitude for a power o ditching. In a forced landing situation, do not set the AVIONICS MASTER switch or the airplane MASTER switch to the OFF position until a landing is assured. When these switches are in the OFF position, the airplane electrical systems are de-energized. Before performing a forced landing, especially in remote and mountain­ous areas, activate the ELT trans­mitter by positioning the cockpit­mounted switch to the ON position.
LANDING WITHOUT ELEVATOR CONTROL
Trim for horizontal flight (with an airspeed of approximately 65 kias and flaps set to 20°) by using throttle and elevator trim controls. Then do not change the elevator trim control setting; control the glide angle by adjusting power exclusively. At the landing flare (round-out), the nose
down moment resulting from pow-
er reduction is an adverse factor
and the airplane may land on the
nose wheel. Consequently, at flare,
the elevator trim control should be
adjusted toward the full nose up
position and the power adjusted so
that the airplane will rotate to the
horizontal attitude for touchdown.
Close the throttle at touchdown.
FIRES
Although engine fires are extremely
rare in flight, the steps of the appro-
priate checklist should be followed
if one is encountered. Aer comple-
tion of this procedure, execute a
forced landing. Do not attempt to
restart the engine. The initial indi-
cation of an electrical fire is usually
the odor of burning insulation. The
checklist for this problem should re-
sult in elimination of the fire.
TOTAL VACUUM
SYSTEM FAILURE
If both the vacuum pumps fail in
flight, the directional indicator and
attitude indicator will be disabled,
and the pilot will have to rely on the
turn coordinator if he inadvertently
flies into clouds. If an autopilot is in-
stalled, it too may be aected. The
following instructions assume that
only the electrically powered turn
coordinator is operative, and that
the pilot is not completely profi-
cient in instrument flying.
SPINS
NEVER INTENTIONALLY SPIN an air-
cra that is not designed and built to
be spun (aerobatic aircra).
Should an inadvertent spin oc­cur, the following recovery proce­dure should be used:
1. Retard throttle to idle position.
2. Place ailerons in neu-
tral position.
3. Apply and hold full rud-
der opposite to the di-
rection of rotation.
4. Just after the rudder reaches
the stop, move the control
wheel briskly forward far enoughto break the stall. Full down elevator may be required at aft center of gravity loadings to as­sure optimum recoveries.
5. Hold these control inputs until rotation stops. Premature relaxation of the control inputs may extend the recovery.
6. As rotation stops, neutralize rudder, and make a smooth recovery from the resulting dive.
NOTE: If disorientation precludes a vi­sual determination of the direction of rotation, the symbolic airplane in the turn coordinator may be referred to for this information.
ROUGH ENGINE OPERATION OR LOSS OF POWER
SPARK PLUG FOULING
A slight engine roughness in flight may be caused by one or more spark plugs becoming fouled by carbon or lead deposits. This may be verified by turning the ignition switch momentarily from BOTH to either L or R position. An obvious power loss in single ignition op­eration is evidence of spark plug or magneto trouble. Assuming that spark plugs are the more likely cause, lean the mixture to the rec­ommended lean setting for cruis­ing flight. If the problem does not clear up in several minutes, deter­mine if a richer mixture setting will produce smoother operation. If not, proceed to the nearest airport for repairs using the BOTH position of the ignition switch unless ex­treme roughness dictates the use of a single ignition position.
MAGNETO MALFUNCTION
A sudden engine roughness or mis­firing is usually evidence of magne­to problems. Switching from BOTH to either L or R ignition switch po­sition will identify which magneto is malfunctioning. Select dierent power settings and enrichen the mixture to determine if continued operation on BOTH magnetos is possible. If not, switch to the good
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magneto and proceed to the near­est airport for repairs.
ENGINE-DRIVEN FUEL PUMP FAILURE
Failure of the engine-driven fuel pump will result in an immediate loss of engine power, similar to fuel exhaustion or starvation, but while operating from a fuel tank contain­ing adequate fuel. A sudden reduc­tion in indicated fuel flow will occur just before loss of engine power. If the engine-driven fuel pump fails, immediately set the auxiliary fuel pump switch (FUEL PUMP) to the ON position to restore engine pow- er. The flight should be terminated as soon as practical and the engine­driven fuel pump repaired.
LOW OIL PRESSURE
If the low oil pressure annunciator (OIL PRESS) illuminates and oil temperature remains normal, the oil pressure sending unit or relief valve may be malfunctioning. Land at the nearest airport to inspect the source of trouble. If a total loss of oil pressure is accompanied by a rise in oil temperature, there is good reason to suspect an engine failure is imminent. Reduce engine power immediately and select a suitable forced landing field. Use only the minimum power required to reach the desired touchdown spot.
ELECTRICAL POWER SUPPLY SYSTEM MALFUNCTIONS
Malfunctions in the electrical pow­er supply system can be detected by periodic monitoring of the am­meter and low voltage annuncia­tor (VOLTS ); however, the cause of these malfunctions is usually dii­cult to determine. A broken alterna­tor drive belt or wiring is most likely the cause of alternator failures, al­though other factors could cause the problem. A defective alternator control unit can also cause malfunc­tions. Problems of this nature con­stitute an electrical emergency and should be dealt with immediately. Electrical power malfunctions usu­ally fall into two categories: exces-
sive rate of charge and insuicient rate of charge. The following para­graphs describe the recommended remedy for each situation.
EXCESSIVE RATE OF CHARGE
Aer engine starting and heavy electrical usage at low engine speeds (such as extended taxiing) the battery condition will be low enough to accept above normal charging during the initial part of a flight. However, aer thirty min­utes of cruising flight, the ammeter should be indicating less than two needle widths of charging current. If the charging rate were to remain above this value on a long flight, the battery would overheat and evapo­rate the electrolyte at an excessive rate. Electronic components in the electrical system can be adversely aected by higher than normal volt­age. The alternator control unit in­cludes an overvoltage sensor which normally will automatically shut down the alternator if the charge voltage reaches approximately 31.5 volts. If the overvoltage sensor mal­functions, as evidenced by an ex­cessive rate of charge shown on the ammeter, the alternator should be turned o, nonessential electrical equipment turned o and the flight terminated as soon as practical.
INSUFFICIENT RATE OF CHARGE
The low voltage annunciator (VOLTS ) may come on and amme-
ter discharge indications may occur during low RPM conditions with an electrical load on the system, such as during a low RPM taxi. Under these conditions, the annuciator will go o at higher RPM.
If the overvoltage sensor should
shut down the alternator and trip the alternator circuit breaker (ALT FLD), or if the alternator output is low, a discharge rate will be shown on the ammeter followed by illumi­nation of the low voltage annuncia­tor (VOLTS ). Since this may be a “nui­sance” trip out, an attempt should be made to reactivate the alternator system. To reactivate, set the avion­ics master switch to the OFF posi­tion, check that the alternator circuit breaker (ALT FLD) is in, then set both sides of the master switch to the OFF position and then to the ON posi­tion. If the problem no longer exists, normal alternator charging will re­sume and the low voltage annuncia­tor (VOLTS ) will go o. The avionics master switch may then be returned to the ON position. If the annuncia­tor illuminates again, a malfunction is confirmed. In this event, the flight should be terminated and/or the cur­rent drain on the battery minimized because the battery can supply the electrical system for only a limited period of time. Battery power must be conserved for later operation of the wing flaps and, if the emergency occurs at night, for possible use of the landing lights during landing.
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A detailed look at the various parts and systems of the C172.
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T
HIS SECTION PROVIDES description
and operation of the airplane and its systems.
FLIGHT CONTROLS
The airplane’s flight control system consists of conventional aileron, rudder, and elevator control surfac­es. The control surfaces are manu­ally operated through cables and mechanical linkage using a control wheel for the ailerons and eleva­tor, and rudder/brake pedals for the rudder.
TRIM SYSTEM
A manually operated elevator trim system is provided. Elevator trim­ming is accomplished through the elevator trim tab by utilizing the vertically mounted trim control wheel in the cockpit. Forward rota­tion of the trim wheel will trim nose down; conversely, a rotation will trim nose up.
INSTRUMENT PANEL
The instrument panel is of all-metal construction, and is designed in segments to allow related groups of instruments, switches and controls to be removed without removing the entire panel. For specific de­tails concerning the instruments, switches, circuit breakers, and con­trols on the instrument panel, refer to related topics in this section.
PILOT PANEL LAYOUT
Flight instruments are contained in a single panel located in front
of the pilot. These instruments are designed around the basic “T” con­figuration. The gyros are located immediately in front of the pilot, and arranged vertically over the control column. The airspeed in­dicator and altimeter are located to the le and right of the gyros, respectively. The remainder of the flight instruments are clustered around the basic “T”. An annuncia­tor panel is located above the al­timeter and provides caution and warning messages for fuel quan­tity, oil pressure, low vacuum and low voltage situations.
To the right of the flight instru-
ments is a sub panel which contains engine tachometer and various navigational heading instruments. To the le of the flight instruments is a sub panel which contains a le/ right fuel quantity indicator, an oil temperature/oil pressure indicator, a vacuum gage/ammeter, an EGT/ fuel flow indicator, a digital clock/ OAT indicator and the avionics cir­cuit breaker panel.
Below the engine and flight in-
struments are circuit breakers and switches for the airplane systems and equipment. Master, Avionics Master and Ignition Switches are also located in this area of the pan­el. The parking brake control is posi­tioned below the switch and circuit breaker panel.
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COCKPIT FAMILIARIZATION
The center panel contains various avionics equipment arranged in a vertical rack. This arrangement allows each component to be re­moved without having to access the backside of the panel. Below the panel are the throttle, mixture, alter­nate static air and lighting controls.
1. Oil Temp and Oil Pressure Indicator.
2. Fuel Quantity Indicator.
3. Vacuum Gauge and Ammeter.
4. EGT/Fuel Flow Indicator.
5. Digital Clock/O.A.T. Indicator.
6. Turn Indicator.
7. Airspeed Indicator.
8. Directional Gyro.
9. Attitude Indicator.
10. Tachometer.
11. Vertical Speed Indicator.
12. Altimeter.
13. Annunciator Panel.
14. ADF Bearing Indicator.
15. Course Deviation and Glide
Slope Indicators.
16. GPS Receiver.
17. Audio Control Panel.
18. NAV/COM Radio #1
19. NAV/COM Radio #2
20. ADF Receiver.
21. Transponder.
22. Autopilot.
23. Hour Meter.
24. Cabin Air Control.
25. Cabin Heat Control.
26. Flap Switch and Position Indicator.
27. Mixture Control.
28. Alternate Static Air Control.
29. Throttle Control.
30. Radio and Panel Dimming Control.
31. Glareshield and Pedes-
tal Dimming Control.
32. Avionics Master Switch.
33. Pitot Heat Switch.
34. External Lighting Switches.
35. Fuel Pump Switch.
36. Battery Master Switch.
37. Ignition Switch.
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38. Controls Lock.
39. Parking Brake.
40. Elevator Trim Control
and Position Indicator.
41. Fuel Selector.
42. Fuel Shutoff Valve Control.
43. Pilots Manual.
GROUND CONTROL
Eective ground control while taxi­ing is accomplished through nose wheel steering by using the rudder pedals; le rudder pedal to steer le and right rudder pedal to steer right. When a rudder pedal is depressed, a spring loaded steering bungee (which is connected to the nose gear and to the rudder bars) will turn the nose wheel through an arc of ap­proximately 10° each side of center. By applying either le or right brake, the degree of turn may be increased up to 30° each side of center.
WING FLAP SYSTEM
The single-slot type wing flaps, are extended or retracted by position­ing the wing flap switch lever on the instrument panel to the desired flap deflection position. The switch lever is moved up or down in a slot­ted panel that provides mechani­cal stops at the 10°, 20° and 30° positions. To change flap setting, the flap lever is moved to the right to clear mechanical stops at the 10° and 20° positions. A scale and pointer to the le of the flap switch indicates flap travel in degrees. The wing flap system circuit is protected by a 10- ampere circuit breaker, la­beled FLAP, on the le side of the control panel.
LANDING GEAR SYSTEM
The landing gear is of the tricycle type, with a steerable nose wheel and two main wheels. Wheel fair­ings are optional equipment for both the main and nose wheels. Shock absorption is provided by the tubular spring steel main land­ing gear struts and the air/oil nose gear shock strut. Each main gear wheel is equipped with a hydrauli­cally actuated disc type brake on the inboard side of each wheel.
CONTROL LOCKS
A control lock is provided to lock the aileron and elevator control surfac­es to prevent damage to these sys­tems by wind bueting while the air­plane is parked. The lock consists of a shaped steel rod and flag. The flag identifies the control lock and cau­tions about its removal before start­ing the engine. To install the control lock, align the hole in the top of the pilot’s control wheel sha with the hole in the top of the sha collar on the instrument panel and insert the rod into the aligned holes. Installa­tion of the lock will secure the aile­rons in a neutral position and the elevators in a slightly trailing edge down position. Proper installation of the lock will place the flag over the ignition switch. In areas where
high or gusty winds occur, a control surface lock should be installed over the vertical stabilizer and rudder. The control lock and any other type of locking device should be removed prior to starting the engine.
ENGINE
The airplane is powered by a hori­zontally opposed, four cylinder, overhead valve, air cooled, fuel injected engine with a wet sump lubrication system. The engine is a Lycoming Model IO-360-L2A and is rated at 160 horsepower at 2400 RPM. Major accessories include a starter and belt driven alternator mounted on the front of the engine, and dual magnetos, dual vacuum pumps, and a full flow oil filter mounted on the rear of the engine accessory case.
ENGINE CONTROLS
Engine power is controlled by a throttle located on the switch and control panel above the center ped­estal. The throttle is open in the full forward position and closed in the full a position. A friction lock, which is a round knurled knob, is located at the base of the throttle and is operated by rotating the lock clockwise to increase friction or counterclockwise to decrease it.
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The mixture control, mounted ad­jacent to the throttle control, is a red knob with raised points around the circumference and is equipped with a lock button in the end of the knob. The rich position is full forward, and full a is the idle cuto position.
ENGINE INSTRUMENTS
Engine operation is monitored by the following instruments: oil pres­sure/oil temperature indicator, ta­chometer and exhaust gas tempera­ture (EGT) indicator. In addition, the annunciator panel contains a red OIL PRESS annunciator which comes on when the oil pressure is low.
Oil pressure signals are generated from an oil pressure line/transducer combination. An oil pressure line is routed from the upper front of the engine case to the rear engine bale. At the bale, the oil pressure line is connected to a transducer. This transducer produces an electrical signal which is translated into a pres sure reading by the oil pressure gage located on the LH instrument panel.
In addition, a separate low oil pressure indication is provided through the panel annunciator. This annunciator is wired to a pressure switch located on the rear of the en­gine accessory case.
When oil pressure is below 20 PSI, the switch grounds and com­pletes the annunciator circuit, illu­minating the red OIL PRESS light. When pressure exceeds 20 PSI, the ground is removed and the OIL PRESS annunciator goes out.
NOTE: The low oil pressure switch is also connected to the hour (Hobbs) meter. When pressure exceeds 20 PSI, a ground is supplied to the hour meter, completing the hour meter circuit.
Oil temperature signals are gener­ated from a resistance-type probe lo­cated in the engine accessory case. As oil temperature changes, the probe resistance changes. This resistance is translated into oil temperature read ings on the cockpit indicator.
The engine driven mechanical tachometer is located on the in-
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strument panel to the right of the pilot’s control wheel. The instru­ment is calibrated in increments of 100 RPM and indicates both engine and propeller speed. An hour meter in the lower section of the dial re­cords elapsed engine time in hours and tenths. Instrument markings include the normal operating range (green arc) from 1900 to 2400 RPM.
The exhaust gas temperature (EGT) indicator is located on the LH instrument panel as part of the EGT/ Fuel Flow indicator. Since exhaust gas temperature varies with fuel-air ration (mixture), density altitude, throttle position and RPM, the in­strument is a useful aid in adjust­ing the mixture for best economy or performance. The EGT indicator allows the pilot to lean (reduce the proportion of fuel in the fuel-air mixture) to a known value using the maximum or “peak” exhaust gas temperature as a reference. An index pointer which can be po­sitioned manually is provided for the pilot to mark the location of the peak. Never lean using EGT when operating at more than 80% power
The EGT system uses a thermo­couple in the in the engine exhaust (tailpipe) to supply a voltage pro­portional to exhaust gas tempera­ture. The EGT indicator responds to the voltage developed by the
thermocouple. As the mixture is leaned (from full rich), the exhaust gas temperature will increase to a maximum value as the stoichio­metric (most chemically eicient) fuel-air ratio is achieved and will decrease if the mixture continues to be leaned.
MY ENGINE IS SMOKING
Remember, your engine is a piston­powered air pump. Valves open, a piston sucks in air / fuel, ignites it, another valve opens on the next stroke, and it ejects the burned mix­ture out the exhaust. During this time, oil below is lubricating those cylinder walls and piston rings keep that oil below and out of the combustion chamber. Well, all the above is how things are supposed to work, but as all things in life, nothing is perfect.
BLUE SMOKE
If your cylinders are worn or dam­aged, the cylinders can suck oil up past these rings. This oil is then present when the chamber com­busts, burning it, and ejecting it. Two things happen. You will see blue smoke coming out the exhaust and oil sediments will build inside your combustion chamber, slowly degrading that cylinder’s ability to properly work.
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BLACK SMOKE
Your engine is a vacuum pump, sucking in an air / fuel mixture, ig­niting it, then ejecting the burned remains. However, if you have a bad cylinder, a faulty ignition, fouled plugs, or fuel injection issues, the complete burning of the air / fuel mixture can be compromised. The result is black smoke (unburned fuel) seen coming out of the cyl­inders. If you see black smoke, get the aircra on the ground and to a maintenance facility to find the cause of the problem.
ENGINE LUBRICATION SYSTEM
The engine utilizes a full pressure, wet sump-type lubrication system with aviation grade oil used as the lubricant. The capacity of the en­gine sump (located on the bottom of the engine) is eight quarts. Oil is drawn from the sump through an oil suction strainer screen into the engine-driven oil pump.
An oil filler cap/oil dipstick is lo­cated at the right rear of the engine. The filler cap/ dipstick is accessible through an access door on the top right side of the engine cowling. The engine should not be operated on less than five quarts of oil. For extended flight, fill to eight quarts (dipstick indication only). For en­gine oil grade and specifications, refer to of this handbook.
OIL PRESSURE
Oil is the lifeblood of your engine. The countless metal parts in motion depend on constantly having a film of oil covering and separating them. Theoretically, there should be no metal on metal contact, but pressur ized oil in between. Some times sim­ply having oil continuously splashed on the part is enough, yet other times actual pressure is required to keep these metal parts separated. The heavy cranksha that is responsible for twisting the propeller is one part that is in critical need of this pres sure at all times. Running the engine without oil pressure for just minutes is enough to seize up the engine.
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OIL TEMPERATURE
Understanding how temperature af­fects the viscosity of the lubricant is very important (viscosity is the term used to describe the lubricants re­sistance to flow). As your engine oil increases in temperature, it’s vis­cosity decreases, which means that it flows more freely. And vice-versa, as the lubricant cools down, it’s vis­cosity increases, making it more re­sistant to flow.
Accusim models this eect of oil viscosity, so understanding how it aects you, the pilot, is important.
When you start your engine on a cold morning, know that the oil in­side your engine has a high viscosi­ty. You must be respectful of this, as pushing an engine with thick, cold oil can cause premature oil system leaks or worse.
If you must start a very cold en­gine, give it just enough throttle to keep it running (not so low that it is struggling to run). Hold the idle at the lowest possible RPM and wait for the oil temperature to rise. As it rises, the oil will thin, and you may also notice the RPM actually increase due to the thinner oil being easier to push through all those small areas. So ultimately, as the oil temperature rises the oil pressure drops.
IGNITION AND STARTER SYSTEM
Engine ignition is provided by two engine-driven magnetos, and two spark plugs in each cylinder. The right magneto fires the lower right and upper le spark plugs, and the le magneto fires the lower le and upper right spark plugs. Normal operation is conducted with both magnetos due to the more com­plete burning of the fuel/air mixture with dual ignition.
Ignition and starter operation is controlled by a rotary-type switch located on the le switch and con­trol panel. The switch is labeled clockwise, OFF, R, L, BOTH, and START. The engine should be oper­ated on both magnetos (BOTH posi­tion) except for magneto checks. The R and L positions are for checking
purposes and emergency use only. When the switch is rotated to the spring loaded START position, (with the master switch in the ON posi­tion), the starter contactor is closed and the starter, now energized, will crank the engine. When the switch is released, it will automatically return to the BOTH position.
ELECTRIC STARTER
The C172 Trainer has a direct-drive, electric starter, which functions very much the same way as the starter used in automobiles.
Turning the starter on, engages the starter motor to the engine, and it cranks the engine over with electricity. As the engine is turning over, the pilot is providing the en­gine with all of its fuel and ignition requirements, with the expectation
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AIRPLANE & SYSTEMS DESCRIPTION
the engine starts firing (combust­ing), and begins to run on its own power (using fuel and spark).
Once the engine reaches a cer­tain speed, the starter motor auto­matically disengages and the en­gine runs free,
AIR INDUCTION SYSTEM
The engine air induction system receives ram air through an intake on the lower front portion of the engine cowling. The intake is cov­ered by an air filter which removes dust and other foreign matter from the induction air. Airflow passing through the filter enters an air box. The air box has a spring-loaded alternate air door. If the air induc­tion filter should become blocked, suction created by the engine will open the door and draw unfiltered air from inside the lower cowl area. An open alternate air door will re­sult in an approximate 10% power loss at full throttle. Aer passing through the air box, induction air enters a fuel/air control unit under the engine, and is then ducted to the engine cylinders through intake manifold tubes.
EXHAUST SYSTEM
Exhaust gas from each cylinder passes through riser assemblies to a muler and tailpipe. Outside air is pulled in around shrouds which are constructed around the outside of the muler to form heating cham­bers which supply heat to the cabin.
COOLING SYSTEM
Ram air for engine cooling enters through two intake openings in the front of the engine cowling. The cooling air is directed around the cylinders and other areas of the engine by baling, and is then ex­hausted through an opening at the bottom a edge of the cowling. No manual cowl flap cooling system control is required.
PROPELLER
The Cessna 172R comes stock from the factory with a two-bladed, fixed-pitch, 75” diameter propeller.
On the real airplane (and in the Accu-Sim maintenance han gar), you can replace this with the same propeller that came in stalled on the Cessna 172S. This higher performance propeller has a flatter pitch, resulting in less resistance that allows the engine to run at a higher RPM under the same conditions.
So, for example, if you hold your brakes on a 172R and apply full power, the engine will peak at about 2,100RPM. Doing the same exercise on a 172S, the engine will peak somewhere between 2,300­2,400RPM. The engine therefore is creating more horsepower on your takeo run with the flatter, higher­RPM 172S propeller.
However, on the other hand, the 172R propeller will cruise at a lower RPM, resulting in better fuel econo­my and a quieter cabin.
Just like you own airplane, the choice is yours.
FUEL SYSTEM
The airplane fuel system consists of two vented integral fuel tanks (one tank in each wing), a three-position selector valve, auxiliary fuel pump, fuel shuto valve, fuel strainer, en­gine driven fuel pump, fuel/air con­trol unit, fuel distribution valve and fuel injection nozzles.
FUEL DISTRIBUTION
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Fuel flows by gravity from the two wing tanks to a three-position se-
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lector valve, labeled BOTH, RIGHT and LEFT and on to the reservoir tank. From the reservoir tank fuel flows through the auxiliary fuel pump, past the fuel shuto valve, through the fuel strainer to an en­gine driven fuel pump.
From the engine driven fuel pump, fuel is delivered to the fuel/ air control unit, where it is metered and directed to a fuel distribution valve (manifold) which distributes it to each cylinder. Fuel flow into each cylinder is continuous, and flow rate is determined by the amount of air passing through the fuel/air control unit.
FUEL INDICATING
Fuel quantity is measured by two float type fuel quantity transmitters (one in each tank) and indicated by an electrically operated fuel quantity indicator on the le side of the instru ment panel. The gauges are marked in gallons of fuel. An empty tank is in dicated by a red line and the number
0. When an indicator shows an empty tank, approximately 1.5 gallons re main in each tank as unusable fuel. The indicators should not be relied upon for accurate readings during skids, slips, or unusual attitudes.
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Each fuel tank also incorporates warning circuits which can detect low fuel conditions and erroneous transmitter messages. Anytime fuel in the tank drops below ap­proximately 5 gallons (and remains below this level for more than 60 seconds), the amber LOW FUEL message will flash on the annun­ciator panel for approximately 10 seconds and then remain steady amber. The annunciator cannot be turned o by the pilot. If the le tank is low, the message will read L LOW FUEL. If the right tank is low, the message will read LOW FUEL R. If both tanks are low, the message will read L LOW FUEL R.
In addition to low fuel annun­ciation, the warning circuitry is designed to report failures with each transmitter caused by shorts, opens or transmitter resistance which increases over time. If the circuitry detects any one of these conditions, the fuel level indicator needle will go to the OFF position (below the 0 mark on the fuel in
­dicator), and the amber annuncia­tor will illuminate. If the le tank transmitter has failed, the mes
­sage will read L LOW FUEL. If the right tank transmitter has failed, the message will read LOW FUEL R. If both tanks transmitters have failed, the message will read L LOW FUEL R.
Fuel pressure is measured by use of a transducer mounted near the fuel manifold. This transduc
­er produces an electrical signal which is translated for the cock
­pit-mounted indicator in gallons­perhour.
surface of the le wing near the wing strut. Both fuel filler caps are also vented.
REDUCED TANK CAPACITY
The airplane may be serviced to a reduced capacity to permit heavi­er cabin loadings. This is accom­plished by filling each tank to the bottom edge of the fuel filler tab, thus giving a reduced fuel load of
17.5 gallons usable in each tank.
FUEL SELECTOR VALVE
The fuel selector valve should be in the BOTH position for takeo, climb, landing, and maneuvers that involve prolonged slips or skids of more than 30 seconds. Operation from either LEFT or RIGHT tank is reserved for cruising flight.
NOTE: When the fuel selector valve handle is in the BOTH position in cruising flight, unequal fuel flow from each tank may occur if the wings are not maintained exactly level. Result
­ing wing heaviness can be alleviated gradually by turning the selector valve handle to the tank in the “heavy” wing. It is not practical to measure the time required to consume all of the fuel in one tank, and, aer switching to the opposite tank, expect an equal duration from the remaining fuel. The airspace in both fuel tanks is intercon
­nected by a vent line and, therefore, some sloshing of fuel between tanks
can be expected when the tanks are nearly full and the wings are not level.
NOTE: When the fuel tanks are  full or less, prolonged uncoordinated flight such as slips or skids can un
­cover the fuel tank outlets. Therefore, if operating with one fuel tank dry or if operating on LEFT or RIGHT tank when  full or less, do not allow the airplane to remain in uncoordinated flight for periods in excess of 30 seconds.
FUEL DRAIN VALVES
The fuel system is equipped with drain valves to provide a means for the examination of fuel in the system for contamination and grade. The system should be examined before each flight and aer each refueling, by using the sampler cup provided to drain fuel from each wing tank sump and the fuel strainer sump. If any evidence of fuel contamination is found, it must be eliminated in ac­cordance with the Preflight Inspec­tion checklist. If takeo weight limi­tations for the next flight permit, the fuel tanks should be filled aer each flight to prevent condensation.
FUEL VENTING
Fuel system venting is essential to system operation. Blockage of the system will result in de
­creasing fuel flow and eventual engine stoppage. Venting is ac
­complished by an interconnect­ing line from the right fuel tank to the le tank. The le fuel tank is vented overboard through a vent line, equipped with a check valve, which protrudes from the bottom
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BRAKE SYSTEM
The airplane has a single-disc, hy­draulically actuated brake on each main landing gear wheel. Each brake is connected, by a hydraulic line, to a master cylinder attached to each of the pilot’s rudder ped­als. The brakes are operated by ap­plying pressure to the top of either the le (pilot’s) or right (copilot’s) set of rudder pedals, which are in­terconnected. When the airplane is parked, both main wheel brakes may be set by utilizing the parking brake which is operated by a handle under the le side of the instrument panel. To apply the parking brake, set the brakes with the rudder ped­als, pull the handle a, and rotate it 90° down.
For maximum brake life, keep the brake system properly main­tained, and minimize brake usage during taxi operations and land­ings.
With Accu-Sim, we increase the likelihood of hearing brake noise and squeals as the breaks age. Hearing the occasional squeal is normal, but if your breaks start making noise regularly, bring the plane into the maintenance hangar for a check.
ELECTRICAL SYSTEM AND BATTERY
Accu-Sim installs an authentic period battery into a feature-rich electrical system, thanks to close consultation with our own on-sta electrical engineer and high time pilots. Batteries suer from reduced capacity as they age, have a limited output (34 amp hours), can over­heat if you demand too much from them, and can even load up your entire system if you have a brand new, but dead battery on-line. (ever try to jump start a car with a dead battery and nothing happens? You have to disconnect the dead battery and try again, since the dead bat­tery is stealing all the electricity). The physical laws governing elec­tricity are inexorable as those which govern running water. Our latest and most sophisticated version
of Accu-Sim accurately replicates those physical laws and permits you to see the electrical system at work, via the ammeter on your elec­trical panel and through sounds and behaviour of the various elec­trically driven systems.
VOLTS, AMPS, WATTS, WHAT DOES THIS ALL MEAN?
Without getting too technical, the pilot in command must understand the basics of what is happening in the aircra’s electrical system and components. Volts X Amps = watts. If we use a water hose as an analogy, volts would be the water pressure, amps would be the hose width, and watts would be the amount / rate of water coming out the end. You could have, for example, a 120 volt, 1 amp light bulb would be the same brightness as a 12 volt, 100 amp bulb. The high voltage system is sending high pressure down a small pipe, and the low voltage system is sending low pressure down a large pipe, but each putting out the same amount of water (watts).
If you take a huge draw, for ex­ample running an electric engine starter, voltage will plummet as the battery struggles to supply this current. Your Ammeter will show the current draw. However, play with your lights, pitot heat, etc. and watch how these little changes aect these systems. Remember, your electrical system has a bat­tery and an engine driven electri­cal generator. The battery puts out about 24 volts, while the genera­tor puts out a little more (about 28 volts). This allows your generator to not only drive all of the systems,
but charge the battery at the same time. Remember, your generator is powered by the engine speed, and it does not reach it’s full capacity until about 1,500 RPM. Watch your meters, and you will see and enjoy a genuine electrical system in action.
In addition, weather aects a battery’s performance. Fortunately, you can always visit your mainte­nance hangar for a quick charge or replacement. If you use your bat­tery wisely and correctly, it will last a long time.
ELECTRICAL SYSTEM DESCRIPTION
The airplane is equipped with a 28­volt, direct current electrical sys­tem. The system is powered by a beltdriven, 60-amp alternator and a 24-volt battery, located on the le forward side of the firewall. Power is supplied to most general electri­cal circuits through a split primary bus bar, with an essential bus wired between the two primaries to pro­vide power for the master switch, annunciator circuits and interior lighting.
Each primary bus bar is also con­nected to an avionics bus bar via a single avionics master switch. The primary buses are on anytime the master switch is turned on, and are not aected by starter or external power usage. The avionics buses are on when the master switch and avionics master switch are in the ON position.
The airplane uses a power distri­bution module (J-Box), located on the le forward side of the firewall, to house all relays used throughout the airplane electrical system. In addition, the alternator control unit and the external power connector are housed within the module.
ANNUNCIATOR PANEL
An annunciator panel (with integral toggle switch) is located on the le side of the instrument panel and provides caution (amber) and warn­ing (red) messages for selected por­tions of the airplane systems. The annunciator is designed to flash
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messages for approximately 10 sec­onds to gain the attention of the pilot before changing to steady on. The annunciator panel cannot be turned o by the pilot.
Inputs to the annunciator come from each fuel transmitter, the low oil pressure switch, the vacuum transducers and the alternator con­trol unit (ACU). Individual LED bulbs illuminate each message and may be replaced through the rear of the annunciator. Illumination intensity can be controlled by placing the toggle switch to either the DIM or DAY position.
The annunciator panel can be tested by turning the Master Switch On and holding the annunciator panel switch in the TST position. All amber and red messages will flash until the switch is released.
NOTE: When the Master Switch is turned ON, some annunciators will flash for approximately 10 seconds before illuminating steadily. When the annunciator panel switch is toggled up and held in the TST position, all remaining lights will flash until the switch is released.
MASTER SWITCH
The master switch is a split rocker type switch labeled MASTER, and is ON in the up position and o in the down position. The right half of the switch, labeled BAT, controls all electrical power to the airplane. The le half, labeled ALT, controls the alternator.
CAUTION: Prior to turning the master switch on or o, starting the engine or applying an external power source, the avionics power switch, labeled
avionics power, should be turned o to prevent any harmful transient volt age from damaging the avionics equip­ment.
Normally, both sides of the mas­ter switch should be used simulta­neously; however, the BAT side of the switch could be turned on sepa­rately to check equipment while on the ground. To check or use avion­ics equipment or radios while on the ground, the avionics power switch must also be turned on. The ALT side of the switch, when placed in the o position, removes the al­ternator from the electrical system. With this switch in the o position, the entire electrical load is placed on the battery. Continued opera­tion with the alternator switch in the o position will reduce battery power low enough to open the bat­tery contactor, remove power from the alternator field, and prevent al­ternator restart.
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AVIONICS MASTER SWITCH
Electrical power for Avionics Bus 1 and Avionics Bus 2 is supplied through Primary Bus 2 and Primary Bus 1, respectively. A rocker switch, located between the primary and avionics buses, controls current flow to the avionics buses. Placing the rocker switch in the up (ON) po­sition supplies power to both buses simultaneously. Placing the switch in the down (OFF) position removes power from both buses. The switch is located on the lower le side of the instrument panel.
NOTE: On some aircra certified out­side the United States, the avionics master switch may be split. They are
aligned for independent operation of the buses.
With the switch in the o posi­tion, no electrical power will be applied to the avionics equipment, regardless of the position of the master switch or the individual equipment switches. The avionics power switch should be placed in the OFF position prior to turning the master switch on or o, starting the engine, or applying an external power source.
Each avionics bus also incor­porates a separate circuit breaker installed between the primary bus and the avionics master switch. In the event of an electrical malfunc­tion, this breaker will trip and take the eected avionics bus o-line.
AMMETER
The ammeter/vacuum gauge is lo­cated on the lower le side of the instrument panel. It indicates the amount of current, in amperes, from the alternator to the battery or from the battery to the airplane electrical system. When the engine is operating and the master switch is turned on, the ammeter indicates the charging rate applied to the battery. In the event the alternator is not functioning or the electrical load exceeds the output of the al­ternator, the ammeter indicates the battery discharge rate.
LOW VOLTAGE ANNUNCIATION
The low voltage warning annuncia­tor is incorporated in the annuncia­tor panel and activates when volt­age falls below 24.5 volts. If low voltage is detected, the red annun­ciation VOLTS will flash for approxi­mately 10 seconds before illuminat­ing steadily. The pilot cannot turn o the annunciator.
NOTE: Illumination of the low voltage annunciator and ammeter discharge indications may occur during low RPM conditions with an electrical load on the system, such as during a low RPM taxi. Under these conditions, the light will go out at higher RPM.
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CIRCUIT BREAKERS AND FUSES [NOT MODELED ATM]
All circuit breakers inside the air­plane are of the “push to reset” or “switch/breaker” type. The power distribution module (J-Box) uses either “push to reset” circuit break­ers or spade type (automotive style) fuses. One glass type fuse is also used to provide power to the clock.
On aircra using spade type fuses in the power distribution module (J-Box), a spare fuse is also included. If the spare fuse is used, a replacement spare should be ob­tained and reinstalled before the next flight.
LIGHTING SYSTEMS
EXTERIOR LIGHTING
Exterior lighting consists of naviga­tion lights on the wing tips and top of the rudder, a dual landing/taxi light configuration located in the le wing leading edge, a flashing beacon mounted on top of the ver­tical fin, and a strobe light on each wing tip. In addition, two
courtesy lights are recessed into the lower surface of each wing and provide illumination for each cabin door area.
The exterior courtesy lights (and the rear cabin dome light) are turned on by pressing the rear cabin light switch. Pressing the rear cabin light switch again will extinguish the three lights. The remaining ex­terior lights are operated by break­er/switches located on the lower le instrument panel. To activate these lights, place switch in the UP position. To deactivate light, place in the DOWN position.
Glareshield lighting is accom­plished using a fluorescent light recessed into the glareshield. Ped­estal lighting consists of a single, hooded light located above the fuel selector. Panel lighting is ac­complished using individual lights mounted in each instrument and gauge.
CABIN HEATING, VENTILATING AND DEFROSTING SYSTEM
The temperature and volume of air­flow into the cabin can be regulated by manipulation of the push-pull CABIN HT and CABIN AIR controls. Both controls are the double-but­ton locking type and permit inter­mediate settings. For cabin ventila­tion, pull the CABIN AIR knob out.
To raise the air temperature, pull the CABIN HT knob out ap­proximately  to  inch for a small amount of cabin heat. Additional heat is available by pulling the knob out farther; maximum heat is avail­able with the CABIN HT knob pulled out and the CABIN AIR knob pushed full in. When no heat is desired in the cabin, the CABIN HT knob is pushed full in.
Front cabin heat and ventilat­ing air is supplied by outlet holes spaced across a cabin manifold just forward of the pilot’s and copilot’s feet. Rear cabin heat and air is sup­plied by two ducts from the mani­fold, one extending down each side of the cabin to an outlet just a of the rudder pedals at floor level.
Windshield defrost air is also supplied by two ducts leading from the cabin manifold to defroster outlets near the lower edge of the windshield. Two knobs control sliding valves in either defroster outlet to permit regulation of de­froster airflow. Separate adjust­able ventilators supply additional air; one near each upper corner of the windshield supplies air for the pilot and copilot, and two ventila­tors are available for the rear cabin area to supply air to the rear seat passengers. Additionally, there are ventilators located on the forward cabin sidewall area just below the windshield sill area.
PITOT-STATIC SYSTEM AND INSTRUMENTS
The pitot-static system supplies ram air pressure to the airspeed
INTERIOR LIGHTING
Interior lighting is controlled by a combination of flood lighting, glareshield lighting, pedestal light­ing, panel lighting, and radio light­ing. Flood lighting is accomplished using two lights in the front and a single dome light in the rear. All flood lights are contained in the overhead console, and are turned on and o with push type switches located near each light.
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indicator and static pressure to the airspeed indicator, vertical speed indicator and altimeter. The sys­tem is composed of a heated pitot tube mounted on the lower surface of the le wing, an external static port on the lower le side of the forward fuselage, and the associat­ed plumbing necessary to connect the instruments to the sources. The heated pitot system consists of a heating element in the pitot tube, a 5-amp switch/breaker labeled PI- TOT HEAT, and associated wiring. The switch/breaker is located on the lower le side of the instru-
ment panel. When the pitot heat switch is turned on, the element in the pitot tube is heated electrically to maintain proper operation in possible icing conditions. A static pressure alternate source valve is installed below the throttle, and can be used if the external static source is malfunctioning. This valve supplies static pressure from inside the cabin instead of the ex­ternal static port. If erroneous in­strument readings are suspected due to water or ice in the pressure line going to the standard external static pressure source, the alter-
nate static source valve should be pulled on. Pressures within the cabin will vary with open heater/ vents and windows.
AIRSPEED INDICATOR
The airspeed indicator is calibrat­ed in kias. It incorporates a true airspeed window which allows true airspeed (ktas) to be read o the face of the dial. In addition, the indicator incorporates a win dow at the twelve o’clock posi­tion. The window displays true airspeed, and the window at the twelve o’clock position displays pressure altitude overlayed with a temperature scale. Limitation and range markings (in kias) in clude the white arc (33 to 85 kias), green arc (44 to 129 kias), yellow arc (129 to 163 kias), and a red line (163 kias). To find true airspeed, first determine pressure altitude and outside air temperature. Us ing this data, rotate the lower le knob until pressure altitude aligns with outside air temperature in the twelve o’clock window. True air speed (corrected for pressure and temperature) can now be read in the lower window.
VERTICAL SPEED INDICATOR
The vertical speed indicator depicts airplane rate of climb or descent in feet per minute. The pointer is actuated by atmospheric pressure changes resulting from changes of altitude as supplied by the static source.
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ALTIMETER
Airplane altitude is depicted by a barometric type altimeter. A knob near the lower le portion of the indicator provides adjustment of the instrument’s barometric scale to the current altimeter setting.
VACUUM SYSTEM AND INSTRUMENTS
The vacuum system provides suc­tion necessary to operate the atti­tude indicator and the directional indicator. The system consists of two engine-driven vacuum pumps,
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two pressure switches for measur­ing vacuum available through each pump, a vacuum relief valve, a vac­uum system air filter, vacuum oper­ated instruments, a suction gauge, low vacuum warning on the annun­ciator, and a manifold with check valves to allow for normal vacuum system operation if one of the vacu­um pumps should fail.
ATTITUDE INDICATOR
The attitude indicator is a vacuum air-driven gyro that gives a visual indication of flight attitude. Bank attitude is presented by a pointer at the top of the indicator relative to the bank scale which has index marks at 10°, 20°, 30°, 60°, and 90° either side of the center mark. Pitch and roll attitudes are presented by a miniature airplane superimposed over a symbolic horizon area divid­ed into two sections by a white ho­rizon bar. The upper “blue sky” area and the lower “ground” area have pitch reference lines useful for pitch attitude control. A knob at the bot­tom of the instrument is provided
for in-flight adjustment of the sym­bolic airplane to the horizon bar for a more accurate flight attitude indi­cation.
DIRECTIONAL INDICATOR
The directional indicator is a vacu­um air-driven gyro that displays air­plane heading on a compass card in relation to a fixed simulated air­plane image and index. The indica­tor will precess slightly over a peri­od of time. Therefore, the compass card should be set with the magnet­ic compass just prior to takeo, and readjusted as required throughout the flight. A knob on the lower le edge of the instrument is used to adjust the compass card to correct for precession. A knob on the lower right edge of the instrument is used to move the heading bug.
VACUUM INDICATOR
The vacuum indicator is part of the vacuum/amp indicator, located on the lower le corner of the in­strument panel. It is calibrated in inches of mercury and indicates
vacuum air available for operation of the attitude and directional indi­cators. The desired vacuum range is 4.5 to 5.5 inches of mercury. Nor­mally, a vacuum reading out of this range may indicate a system mal­function or improper adjustment, and in this case, the indicators should not be considered reliable. However, due to lower atmospher­ic pressures at higher altitudes, the vacuum indicator may indicate as low as 4.0 in. Hg. at 20,000 feet and still be adequate for normal sys­tem operation.
LOW VACUUM ANNUNCIATION
Each engine-driven vacuum pump is plumbed to a common mani fold, located forward of the fire­wall. From the tee, a single line runs into the cabin to operate the various vacuum system instru ments. This tee contains check valves to prevent back flow into a pump if it fails. Transducers are located just upstream of the tee and measure vacuum output of each pump. If output of the le pump falls below 3.0 in. Hg., the amber L VAC message will flash on the annunciator panel for approxi mately 10 seconds before turning steady on. If output of the right pump falls below 3.0 in. Hg., the amber VAC R message will flash on the annunciator panel for approxi mately 10 seconds before turning steady on. If output of both pumps falls below 3.0 in. Hg., the amber L VAC R message will flash on the annunciator panel for approxi mately 10 seconds before turning steady on.
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CLOCK / O.A.T. INDICATOR
An integrated clock / O.A.T. / voltme­ter is installed in the upper le side of the instrument panel as standard equipment.
STALL WARNING SYSTEM
The airplane is equipped with a pneumatic type stall warning sys­tem consisting of an inlet in the leading edge of the le wing, an air-operated horn near the upper
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le corner of the windshield, and associated plumbing. As the air­plane approaches a stall, the low pressure on the upper surface of the wings moves forward around the leading edge of the wings. This low pressure creates a dierential pressure in the stall warning sys­tem which draws air through the warning horn, resulting in an au­dible warning at 5 to 10 kias above stall in all flight conditions.
CENTER STACK AVIONICS SUITE
We have spent much time develop­ing extra modes and functions that you won’t find in any P3D airplane, like independent DME receiver, pilot­programmable COMM channels and NAV OBS mode. For example, you should pay attention to the autopi­lot. Even though it may look familiar, you need to learn how to operate it properly or you may find you plane going in completely wrong direction.
The Bendix King avionics suite in your Accu-Sim C172 Trainer is so complete, the best source for your information is straight from the manufacturer. Below are links to the latest manuals online:
C172 BENDIXKING SILVER CROWN PLUS AVIONICS
C172 HONEYWELL KAP140 AUTOPILOT
If these links ever change and become unavailable, visit
www.a2asimulations.com/downloads
for the latest information.
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Navigating the 2D panels and taking care of your aircraft.
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HIS SECTION CONTAINS factory rec­ommended procedures for proper ground handling and routine care and servicing of your airplane. It
T
also identifies certain inspection and maintenance requirements which must be followed if your airplane is to retain that new plane performance and dependability. It is wise to follow a planned schedule of lubrication and preventive maintenance based on climatic and flying conditions en­countered in your locality.
Keep in touch with your local Cessna Service Station and take advantage of their knowledge and experience. Your Cessna Service Station knows your airplane and how to maintain it, and will re­mind you when lubrications and oil changes are necessary, as well as other seasonal and periodic services. The airplane should be regularly inspected and main­tained in accordance with informa­tion found in the airplane main­tenance manual and in company issued service bulletins and service newsletters. All service bulletins pertaining to the aircra by serial number should be accomplished
and the airplane should receive re­petitive and required inspections. Cessna does not condone modifi­cations, whether by Supplemen­tal Type Certificate or otherwise, unless these certificates are held and/or approved by Cessna. Other modifications may void warranties on the airplane since Cessna has no way of knowing the full eect on the overall airplane. Operation of an airplane that has been modi­fied may be a risk to the occupants, and operating procedures and performance data set forth in the operating handbook may no lon­ger be considered accurate for the modified airplane.
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FUEL CONTAMINATION
Fuel contamination is usually the result of foreign material present in the fuel system, and may consist of water, rust, sand, dirt, microbes or bacterial growth. In addition, addi­tives that are not compatible with fuel or fuel system components can cause the fuel to become contami­nated. Before each flight and aer each refueling, use a clear sampler cup and drain at least a cupful of fuel from each fuel tank drain location and from the fuel strainer quick drain valve to determine if contaminants are present, and to ensure the air­plane has been fueled with the prop­er grade of fuel. If contamination is detected, drain all fuel drain points including the fuel reservoir and fuel selector quick drain valves and then gently rock the wings and lower the tail to the ground to move any addi­tional contaminants to the sampling points. Take repeated samples from all fuel drain points until all contami­nation has been removed. If, aer repeated sampling, evidence of con­tamination still exists, the airplane should not be flown. Tanks should be drained and system purged by qualified maintenance personnel. All evidence of contamination must be removed before further flight. If the airplane has been serviced with the improper fuel grade, defuel com­pletely and refuel with the correct grade. Do not fly the airplane with contaminated or unapproved fuel. In addition, Owners/Operators who are not acquainted with a particular fixed base operator should be as­sured that the fuel supply has been checked for contamination and is properly filtered before allowing the airplane to be serviced. Fuel tanks should be kept full between flights, provided weight and balance con­siderations will permit, to reduce the possibility of water condensing on the walls of partially filled tanks. To further reduce the possibility of contaminated fuel, routine mainte­nance of the fuel system should be performed in accordance with the airplane Maintenance Manual. Only the proper fuel, as recommended in
Pilot’s Notes are an excellent quick reference while ying.
this handbook, should be used, and fuel additives should not be used unless approved by Cessna and the Federal Aviation Administration.
2D PANELS
The 2D panels are there to provide the extra functionality needed when there is so much additional information available to you, the pilot.
Each 2D panel is accessed by the key-press combination in parenthe­ses aer the 2D panel title.
PILOT’S NOTES (SHIFT 2)
▶ Outside Temp: is the
ambient temperature
outside the aircraft.
▶ Watch Engine Temps: this
warning will display if your engine temperature is nearing danger limits. Corrective action should be carried out immediately if this warning appears.
▶ Cabin Temperature: displays
how comfortable the tem­perature of the cabin feels.
▶ Ground Speed: this is your
speed in relation to the ground in miles/hour and knots.
▶ Endurance: this figure tells you
approximately how long you could remain in powered flight before running out of fuel. This figure will update throughout your flight, and as such you should take into account that during a climb phase, the endurance will be less than once the aircraft is settled in a cruise configuration.
▶ Range: given in statute (sm)
and nautical miles (nm), this figure will give you an ap­proximation of your maximum range under current fuel consumption and airspeed conditions. Again, this figure will change depend­ing on your flight phase.
▶ Fuel Economy: is the cur-
rent fuel burn rate given in gallons/hour (gph), miles/ gallon (mpg) and nauti­cal miles/gallon (nmpg).
▶ Power Settings: this rep-
resents your clipboard, showing you important information for the correct settings for take off, climb and cruise configurations.
▶ Notes: these are a set of
pages (accessed by the small arrow to the right of the page number) that include infor­mation such as actions to be carried out when first entering the cabin, to landing checks.
CONTROLS (SHIFT 3)
Initially designed to provide a means to perform various in cockpit actions whilst viewing the aircra from an external viewpoint, this
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control panel now provides quick access to a number of dierent commands.
From this panel, you can:
▶ Remove the pilot figure from
the external view (only avail­able whilst the engine is not running). Note the visual change in the aircraft balance when you remove the pilot.
▶ Control electrical systems such
as the generator or magnetos.
▶ Toggle aircraft lighting, both
internal and external.
▶ Change the GPS system
installed in your aircraft, from a bracket mounted handheld unit, to panel mounted units, or no GPS installed at all.
▶ Set whether you want
the aircraft to already be in a Cold and Dark state when you first enter it.
▶ Have your aircraft switch to
a “Used” state, where some aircraft components will immediately show signs of wear. Check your maintenance hangar before you go flying, so that you’re aware of the systems and components that you’ll need to keep an eye on.
▶ Turn Accusim dam-
age on and off.
PAYLOAD AND FUEL MANAGER (SHIFT 4)
The payload and fuel manager not only gives you an overview of your current payload, fuel and oil quanti­ties, it is also an interactive loading screen, where you can:
▶ Add and remove pas-
sengers and baggage.
▶ Increase or decrease
pilot, passenger and baggage weights.
▶ Add or remove oil in the
reservoir, and change the oil viscosity depending on seasonal changes.
▶ Add or remove fuel
from the wing tanks.
▶ Change between viewing
weights and measures in imperial or metric format.
The Pilot’s Map is updated in real-time.
▶ View, at a glance, total aircraft
weight, payload weight, and total fuel quantities.
PILOT’S MAP (SHIFT 5)
The pilot’s map gives full and easy access to information that may be found on real maps, and allows this information to be accessed from the cockpit, as opposed to using the default map via the drop-down menus.
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The accompanying panel to the map allows you to select what infor­mation you want to have displayed on the map, from a compass rose to low altitude airways.
Also note that some of the but­ton selections have an increasing amount of information presented with each subsequent button press.
For example, the APT (Airport) button will show the following in­formation:
APT 1: Airport ID.  APT 2: Airport name.  APT 3: Airport elevation.  APT 4: Airport radio
frequencies.
QUICK RADIOS (SHIFT 6)
This small popup panel provides input for your virtual cockpit radios but in a simplified and easy to use manner. This popup features all the amenities of the actual radios but in a singular unit which allows you to control your communication, navi­gation, ADF and transponder radios from a single source.
MAINTENANCE HANGAR (SHIFT 7)
The maintenance hangar is where you can review the current state of your aircra and its major systems. It is one of the core elements to vi­sualizing Accusim at work.
With the invaluable assistance of your local aircra maintenance engi neer/technician, a.k.a “grease mon­key”, you will be able to see a full and in-depth report stating the following:
▶ A summary of your airframe,
engine and propeller installed.
▶ Total airframe hours, and
engine hours since the
last major overhaul.
▶ General condition
of the engine.
▶ Important notes provided
by the ground crew.
From the maintenance han­gar, you can also carry out a com­plete overhaul, by clicking the COMPLETE OVERHAUL button in
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the bottom right corner. This will overhaul the engine and replace any parts that are showing signs of wear or damage, with new or re­conditioned parts.
In this instance, our mechanic has flagged up several issues which would give us cause for concern.
Firstly, he has noted some cylin­der scoring, and secondly that there is a major problem with the cranksha.
In order to fix these issues we need to inspect the engine in great­er detail. By le clicking the “CHECK ENGINE” text on the engine cover, it will open the following window.
COLOUR CODES:
GREEN: OK
YELLOW: WATCH
RED: MUST FIX OR REPLACE
Our mechanic has already stat­ed that there is a serious issue with our cranksha, as can be seen from the highlighted part in red.
Heavy wear or a component fail­ure will be shown in red, and these
components must be replaced.
The cylinders are shown with a yel­low highlight, but these do not have to be replaced, as a yellow highlight is showing us that the components are worn, but not unserviceable.
We can choose to continue flying with the worn components, but extra care should be used and a close eye kept on those systems/components.
COMPRESSION TEST
At the lower right hand corner is a “COMPRESSION TEST” button, which will tell your mechanic to run a high pressure dierential compression test on the engine cylinders.
This is done by compressed air being applied through a regulator gauge to the tester in the cylinder. The gauge would show the total pres sure being applied to the cylinder.
The compressed air would then pass through a calibrated restrictor and to the cylinder pressure gauge. This gauge would show the actual air pressure within the cylinder.
Any dierence in pressure be­tween the two gauges would indi­cate a leak of air past the engine components, whether that is the valves, piston rings, or even a crack in the cylinder wall itself.
The readings that your mechanic presents to you in the “Compression Test Results” in the notes section, will be annotated with the actual amount of pressure read in the cylinder over the actual pressure that was applied to the cylinder through the regulator.
Low compression on a cylinder isn’t nec essarily a terrible thing, because as the en gine picks up in speed, the worn cylinder becomes productive. It is mostly noticed at lower R.P.M.’s where the cylinder may have trouble firing, and also a marked increase in oil consumption may also occur (sometimes with an accompanying blue smoke out of that cylinder during flight).
However, note that this is a read­ing of the general condition of the cylinders, and lower condition does bring additional risks of failure, or even engine fires.
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PRE-FLIGHT INSPECTION (SHIFT 8)
The Pre-Flight Inspection is anoth­er advancement in bringing real life standard operating procedures into P3D.
The inspection system is done in such a way as to emulate mak­ing your walkaround inspection prior to flight.
There are 19 separate check sheets which are accessed by click­ing the arrows in the bottom right corner of the aircra top-down view window.
As you select the next check sheet, you will automatically be moved to the relevant view around the aircra.
It’s not just a case of clicking the next check sheet over and over again however, as there are actions to be carried out and vi sual checks to be made in order to complete the pre-flight correctly. If you miss something, maybe the landing light lens cover on the leading edge is smashed, expect to be notified by your mechanic in the Maintenance Hangar, as his sharp eye will pick up anything you miss.
The checklist itself shows an overview of the aircra, with your walkaround route in black, and dots to highlight the areas where subsequent checks will be carried out.
The check list starts with actions to be carried out in the cockpit, pri­or to your walkaround.
Ensure that the checklist is car­ried out correctly, as checks and ac­tions missed here, will prevent you from carrying out the proper checks during your walkaround.
The first of the external checks covers the tail area. The checklist now has an additional bottom sec­tion in which specific actions can be carried out, or additional views can be accessed as a reference to what to look out for.
By le clicking on an action but­ton, it will either perform an action, i.e. remove the tail tie down, or it will bring up a reference picture. In
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the example below, we’re looking at the elevator hinges.
As part of the walkaround, checking the fuel tank sump quick drain valves is an extremely im­portant check. If water enters the engine, expect a brief interlude of coughing and spluttering, quickly followed by the sound of silence.
The oil dipstick is not only es­sential in gauging the total oil quantity, but also the condition of the oil. As you put hours on your engine, expect the oil to become darker due to suspended par­ticulates that are too fine to be trapped by the filter. The oil also goes through chemical changes, which over time means that the oil isn’t as capable of protecting your engine as it was when new.
PAUSE CONTROL (SHIFT 9)
The pause controls are made available for those times when you need to be away from the simulation.
By le clicking the various boxes, you will turn that pause command on, and for the Altitude, Time and Distance boxes, a plus and minus arrow allow you to change the val­ues for when the pause command will be issued.
If more than one box is switched on, the first trigger to be reached will pause the simulation.
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CREDITS

MICROSOFT AND LOCKHEED MARTIN:
Creators of Prepar3D
PROJECT MANAGEMENT:
Scott Gentile
LEAD ARTIST (3D MODELING, TEXTURING, GAUGES):
Michal Puto
AIRCRAFT PAINTING:
Michal Puto, Marcelo da Silva
PROGRAMMING:
Robert Rogalski, Michal Krawczyk, Krzysztof Sobczak
CONSULTANT:
Dudley Henriques
FLIGHT DYNAMICS:
Scott Gentile, SD Research
VISUAL EFFECTS AND AUDIO:
Scott Gentile
PUBLIC RELATIONS, WEB DESIGN:
Lewis Bloomfield
MANUAL:
Mitchell Glicksman, Scott Gentile & Matt Newton
MANUAL EDITING AND PROOFREADING:
The beta team
MANUAL GRAPHIC DESIGN:
Mark Kee
SPONSORS:
Phillips66 Aviation, Knots2U, Champion Aerospace, ASL Camguard and Concorde Battery
QUALITY CONTROL BETA TEAM:
The world’s most eective and knowledgeable flight simulation beta team, including Cody Bergland, Forest “FAC257” Crooke, Glenn Cummings (GlennC), Ryan “Hog Driver” Gann, Mitchell Glicksman, Captain Jakey, Erwin Schultze (dutch506), Guenter Steiner, Paul “Gypsy Baron” Strogen, Gunter “Snorre” Schneider, Matt “mattgn” Newton, Lewis Bloomfield & Oskar “lonewulf47” Wagner.
VERY SPECIAL THANKS TO OUR FRIENDS AND FAMILIES WHO STUCK BY US AND WORKED HARD TO SUPPORT OUR EFFORTS.
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C172 MANUAL
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