A2A Piper Comanche 250 User Manual

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Ergonomic Advice

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ACCU-SIM COMANCHE 250

CONTENTS

6 30 32 34 38 42

48 52 54

DYNAMIC ELEGANCE

DEVELOPER’S NOTES

FEATURES

QUICK-START GUIDE

ACCU-SIM AND THE COMANCHE 250

ACCU-SIM AND THE COMBUSTION ENGINE

PROPELLERS

GENERAL

LIMITATIONS

62 70 74

84 88

100

PERFORMANCE

WEIGHT AND BALANCE

AIRPLANE & SYSTEM DESCRIPTIONS

EMERGENCY PROCEDURES

EMERGENCY PROCEDURES EXPLAINED

AIRPLANE HANDLING, SERVICE & MAINTENANCE

CREDITS

NORMAL PROCEDURES

DYNAMIC ELEGANCE

Mitchell Glicksman

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O AIRPLANE PERSONIFIES THE EPITHET

“Dynamic Elegance” more aptly than does

the Piper Comanche 250.

The unique conjoining of many superlative aeronautic and aesthetic qualities marks this very special aeroplane. It has been said that if an aeroplane looks right, it will fly right. In this it is supposed that the eye’s natural ability to sense the pleasing proportion and intrinsic eiciency of a design is a reliable predictor of similarly excellent aeronautic performance. The Comanche 250 proves that this adage may be relied upon and bears validity. The Piper Comanche takes its well-deserved place on an illustrious list of aeroplanes which are both so very pleasing to the eyes and which are equally capable of superior performance.

There are many including this writer who hold that the Comanche is among the most beautiful of all General Aviation (GA) aircra, if not the most beautiful. From any angle the Comanche treats the eyes. This is what provides its elegance. Its superlative performance is a matter of record and this provides its dynamism. These two great and rare qualities, beauty and performance would be enough in and of themselves to place the Comanche at the pinnacle of GA aircra, but the Comanche possesses an additional quality, one which, aer all, may be its most endearing.

Of all of the high performance GA aircra the Comanche is arguably the least demanding of the relatively low- time pilot. That this is so is not an accident or a fortuitous circumstance -- William Piper specifically intended that it should be so. The Comanche’s forgiving flight characteristics and its refusal to turn and bite an unwary pilot without plenty of warning, its relatively gentle stall, easy handling at low airspeeds and its overall

delightful handling at all airspeeds are confidence boosters for its fortunate pilots.

The Comanche is also particularly exceptional in that it does not achieve its excellent aerodynamic performance at the expense of interior room and comfort; it is among the roomiest and most comfortable of “high performance” aeroplanes. Neither does the Comanche sacrifice useful load nor its generous weight and balance envelope at the altar of high airspeed. It is a highly capable heavy load hauler and its capacious useful load as well as its ability to safely carry baggage and substantial rear seat passengers without straining its a load limits is far better than its closest competitors of equal horsepower -- including and specifically the V-tail Beechcra Bonanza. Perhaps most importantly, the Comanche does not achieve its performance by the intrinsic design features which compromise stable flying characteristics. Its light airframe weight and its generous, high aspect-ratio, laminar flow wing provides the Comanche with high eiciency as well as a low wing loading.

Accordingly, Comanche pilots and owners are particularly loyal and satisfied, and for good reason; the Comanche delivers extraordinarily dynamic performance while embodying the highest degree of aeronautic elegance.

So, how is it that all of these superlative qualities came together in this aeroplane? Well, therein lays the Comanche’s tale, one redolent of aeronautic expertise, prescience, confidence and also of a fierce competitive spirit. As it happens, it all began a little more than ten years before the first Comanche ever flew.

Once upon a time…

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THE MODERN AGE OF THE PRIVATE AIRPLANE BEGINS — ENTER THE BEECHCRAFT BONANZA

Summer, 1945 -- While the world is joyously celebrating the Allied victory in Europe, World War II is still savagely raging in the Pacific. The United States’ combined armed services along with those of its valiant Allies are pressing forward, island by terrible island at horrific human cost, drawing an ever- tightening noose around the neck of the Imperial Empire of Japan. As the final victory and a new era of peace looms nearer and nearer the American General Aviation (GA) industry made up of companies such as Piper, Cessna, Ryan, Stinson, Luscombe and Beechcra is already making plans for what they expect and fervently hope will come aer the War is finally over. Unfortunately or perhaps inevitably, expectations, which are so oen fragile and which are ultimately as insubstantial as vapour are also as precious as dreams; and like dreams expectations are oen rendered irrelevant and are ultimately crushed by brutish reality. Aer almost four years of stifling limitations incurred by the unavailability of raw materials, machinery and workers, all of which and whom went into the War eort, the GA industry had become, or perhaps more accurately had succumbed to becoming manufacturers of solely that which the War Department required and demanded.

Thus, those American GA companies who persevered performed their needed part as highly regulated cost-plus cogs in the War’s wheels, first under the WPB (War Production Board) and then under the OWM (Oice of War Mobilisation), subject as well to the rules and regulations of the OPA (Oice of Price Administration) and the WMC (War Manpower Commission). Piper, for instance, just as it was beginning to achieve the blessings of it’s longworked- for financial success in the late 1930’s was compelled in 1941 to convert its popular J-3 Cub into a military scout, an artillery spotter, a short- field, short distance transport vehicle for a pilot and a single V. I. P., and for a (mercifully) short while, amazingly, a motorless three-place glider trainer. Cessna turned out the AT-17 “Bamboo Bomber”, a multi-engine trainer, the AT-17, etc., Beechcra built the AT-7 Navigator/C-45/UC-45/CT-128 Expeditor

From its inception the Bonanza was intended to largely appeal to the corporate/business community as we see here. However, in this one we also see a little of the Western, “Camp out with your Bonanza” outdoor flavour which was another intended part of the appeal that Beechcraft wanted to make. There would be a lot more of this kind of appe al in ads to come and all of this coming long before the television show of the same name.

The main picture is interesting. These men must have been as small as elves to have that much head and shoulder room in the Bonanza’s cabin. Also, those guys in the back had better have been very slim and lightweight, the V-tail Bonanza cannot take much of an af t load.

versions of its sturdy and thoroughly excellent twin-engine Model 18, and so on with regard to all within the GA industry.

The irony of it was that for all of the splendid work and muscular energy spent producing aircra for the war eort, none of these very mission- specific wartime airplanes were designed for or expected to ever be made available to the public at any future time. And so, while a small profit (very small to be sure) was earned from their military manufacturing eorts, the commercial aspects of GA manufacturers, at least for the duration of the War, came to a complete halt.

This is not to say that Piper and the other GA manufacturers did not sincerely desire to do their part in helping to win the war. Their oicers and employees were as patriotic as the best Americans and their strenuous eorts substantially enabled the inevitable victory. That being said, as the War progressed they patiently waited and anxiously looked forward to the postwar era wherein they might finally reap the

sweet commercial rewards of their recent sacrifices by selling great shiploads of civilian airplanes to hoards of distinctly aviation- friendly and flight- familiar ex-service pilots.

In the summer of 1945, as the War wound down to its end, the owners, CEOs and Boards of American General Aviation manufacturers expected, or if you prefer, dreamed that their anxiously anticipated heighday was truly nigh. Aer all, they reasoned (with a heavy dose of wishful thinking) that when all of those young aviators come home aer having experi enced the joy and freedom of flying, they would surely wish to continue in a simi lar vein and become owners and pilots of their own airplanes. They further rea soned that when these young men (and some young women as well) having been released from the armed services sal lied forth en masse, clamouring for airplanes to buy, the American GA Industry would be right there, blithely and heartily ready, cheerfully awaiting their chance

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Notice the slow-moving automobile traffic below over which the sleek, sparkling silver Bonanza effortlessly travels.

More “C ampout with your Bonanza”. Business and pleasure combined — irresistible appeal.

Pure business appeal. Note the oil rig pictured. The upscale and super- expensive Bonanza was strongly pitched to the burgeoning oil business.

to supply the anxious needs and desires of these valiant and victorious aerial vet

erans. In any event, it sounded right and no one apparently thought that there was any flaw in that analysis and expectation.

One aircra manufacturer however, Beechcra, did more than merely dream. With the surrender of the Empire of Japan on September 2, 1945 which marked the end of W.W. II, the world commenced to dig itself out of mountains of ruin and rubble, account for and mourn numberless victims, and as soon as might be possible to get on with life in the bright and promising era of Peace. In the United States that which had been interrupted by the war was now busy re-commencing. GA manufacturers were now free to produce aeroplanes for the public with an unlimited supply of necessary materials and workers.

While virtually all of the other GA manufacturers planned on oering pretty much the same aircra or types of aircra that they has built in the pre-war 30’s; Piper oering the J-3 “Cub”, Cessna oering a distinctly pre-war style aeroplane, the 5 seat C-190/195 as well as the two-place, tailwheel equipped C-120, Taylorcra, Aeronca, Stinson and Luscombe all once again oering their pre-war designs; Beechcra had another idea, a new idea.

Beechcra was bent upon producing a brand- new aeroplane, something not

only entirely dierent from anything that they had previously built, but something new and exciting that had not yet been seen in the GA world. This was the seminal Bonanza Model 35 which was to become the airplane that sparked and kick-started post-war modern General Aviation.

Remarkably prescient in every way, Beechcra well-named the new aeroplane, “Bonanza”. Even before Beechcra had actually sold a single aeroplane, it was already a remarkable economic success. Shortly aer its grand introduction to the public by way of press releases and magazine advertisements, corporations, businesses and wealthy professionals placed almost 1,500 orders in advance of its release with thousands more orders soon to come. Without any question the Bonanza was an unqualified and immediate roaring success.

In 1947 Beechcra embarked upon a very powerful and sweeping advertising campaign to debut and introduce to the public what it was confident would create a sea-change in GA aviation. Beechcra was right on all counts.

Let’s take a close look at a variety of advertisements that illustrate the new market Beechcra expected to serve with the Bonanza. Here are some early (1947) ads which were part of the campaign to introduce the Bonanza to the public:

BEECHCRAFT’S BIG IDEA

Designed by Ralph Harmon and his associates in 1945 as the war was coming to an end, the Model 35 Bonanza had its first test flight on December 22, 1945. Incorporating all of what was then known about aerodynamics, aircra structure and aviation technology, the Bonanza’s clean, stressed skin (monocoque) all-metal structure was reminiscent of the recently lionised Spitfires and Mustangs and in virtually every way was a distinct departure from previous mostly fabric covered, fixedundercarriage, tailwheel GA aircra.

The first Bonanza, the Model 35, had a retractable tricycle undercarriage, a distinctive V-tail which was unique for GA aircra and had seats for four adults. The first Bonanzas were originally equipped with an interesting and curious laminated wood, electrically controlled, pilot adjustable, fixed pitch propeller. This was not an automatic constant speed propeller which was a common item even by 1945, but was a variable pitch unit electrically adjustable by the pilot to meet power requirements. Some early Bonanzas that are still flying still have this kind of propeller; however, most of these propellers have been converted to metal blades.

The Model 35 was powered by a simple to manage and inexpensive to run sixcylinder, horizontally opposed, air cooled

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165 hp Continental E-165 engine (O-470 family). High performance GA aircra, including Beechcra’s, had traditionally been powered by large 7 or 9 cylinder, round radial engines which were thirsty of fuel and oil. A moderate sized, horizontally opposed engine in the Bonanza was a breath of fresh air which engendered the colour of progressive modernism while promising low fuel and oil consumption and a much quieter cabin.

Unsurprisingly, the Bonanza spectacularly burst onto the GA market and was undisputedly and justly acclaimed by all to be the first of a new breed of GA aircra.

In 1945 at the time that the Bonanza was being conceptualised, what late in the following decade would become a new GA culture largely populated by casual weekend aviation hobbyists who were primarily relatively low-time VFR-only pilots and who flew in order to take their friends and families alo for pleasant, good-weather aerial jaunts and vacations and to consume that $100 hamburger in a restaurant at some distant airport, did not yet exist, nor could it then have then been foreseen. Accordingly, in 1945 Beechcra’s design philosophy and the targeted market for the Bonanza was, as we shall see, in no way aimed at the part-time aviation aficionados to come, but at an entirely different group of highly experienced pilots who it was expected would own and/or be hired to fly Bonanzas for businesses and corporations.

Beechcra’s goal and expectations for the Bonanza were clear: To create the fastest aeroplane for its horsepower that could carry up to four in relative comfort which would be primarily purchased by prosperous individuals, corporations and businesses to be used as a luxury executive transport flown by experienced, exmilitary service pilots.

Yes, all during the war most Americans hoped for, waited for, and expected that peace would bring forth a brave and prosperous New World, a World which in August, 1945 had finally arrived. Beechcra’s particularly clear prescience was that this New World’s skies would be greatly populated with aircra of all shapes and sizes in general and with its new, game changing Bonanza in particular.

As said, Beechcra’s plan included the idea that those who would mostly be

flying the Bonanza would be primarily those valiant young ex-Army, Navy and Marine Corps aeroplane drivers who had of late been regularly flying and fighting at 40,000’ and at up to 400 MPH +. Many of these soon- to- be Bonanza pilots had regularly flown massive, heavy, fourengine aircra on perilous high-altitude, long-range missions over Europe, East Asia and throughout the Pacific Theatre. It was assumed that they would not likely regard flying the neat and trim little fourseat Bonanza with its 165 h.p. engine to be much of a challenge. These were the pilots whom Beechcra expected would be filling the rolls of those who would be flying corporate V.I.P. s, business oicers and representatives to and from board and sales meetings all over the country in post-war peacetime America. Beechcra’s mission was to see that as many of them as possible would be flying Bonanzas.

Beechcra’s vision turned out to be at least partly true as it was primarily extransport and bomber pilots who filled out applications with businesses and corporations of all kinds to become aerial chaueurs. Apparently most of the fighter pilots had had more than their fill of what was, from their perspective, the “joy” and “thrill” of flying.

What this meant regarding the design of the Bonanza was that Beechcra properly understood that these ex-military pilots would need no coddling when it came to providing an aeroplane suitable for them to fly. Accordingly, taking extra care to design the Bonanza to be a gentle and easy handing aeroplane for a multitude of casual, weekend, sportsman pilots did not appear to be any part of Beechcra’s intent or concern. It seemed that a clean design was paramount, which could be sold most readily, i.e. performance -- high speed, fast climb, long range, eiciency, comfort, as well as owner’s prestige and a kind of modern-world cool sexiness -- everything that makes an aeroplane exciting and satisfying to behold and to fly.

Not surprisingly the Bonanza’s fastgrowing reputation as the “best”, and “most modern” private aeroplane attracted a great many wealthy and wellhealed professionals and “sportsmen”, many of whom had no more than perhaps a few hundred hours flight time, if that much, and who were largely of limited

aeronautic experience. They were used to possessing whatever they wished and could easily aord the newest of the new and the best of the best. Not accidentally Beechcra had placed Bonanza squarely in that class of possessions; but therein was the rub.

All aeroplanes are subject to that most basic law of physics: where one thing is gained, another must be diminished. Accordingly, the design of all aeroplanes necessitates many compromises. For instance, maximum airspeed and performance for available power is generally and most readily obtained at the expense of various other flight characteristics that would, say, make the aeroplane suitable as a casual touring aeroplane, and vice versa. Compromises in design must be made favouring that which the manufacturer sees as its goal for any particular aeroplane. To achieve specific design goals such as high airspeed, comfortable cabin space, long range, heavy load carrying, gentle handling, moderate runway requirements, etc. designers make choices regarding an aircra’s dimensions, geometry, proportion, materials, weight, airfoils, thicknesses, shapes, wing and power loading, etc. In creating a design which would extract maximum airspeed from available power, the Bonanza’s designers clearly made specific choices and compromises, many of which did not favour the low-time pilot.

Aer a tragic V-tail separation during early flight testing in 1946 which caused the death of the test pilot and extensive re-design and re-testing of the tail surfaces (but not to a suicient degree as we shall see), the existing problems seemed to be cured and all went well. By the end of 1947 the first gleaming silver Bonanzas rolled o the assembly lines. In its class and for its time it was the epitome of GA aeronautical design and engineering -- fast, beautiful and looking like nothing that had come before. Sure, it was pricey at the then great sum of $7,975.00 ($84,613.32 in

2015), however a 2015 Bonanza G36 costs approximately $691,390 depending upon installed electronics, equipment, etc.), but to its well-healed purchasers price was no object. In fact, the Bonanza’s high price guaranteed exclusivity and granted its owner distinct prestige and pride of ownership.

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The would-be fighter pilot ’s dream, the Cavalier Mustang appe ars here in civilian pain t. Many were finished in “military” colours and some wi th authentic camouflage and markings. While surely an exciting prospective mount for any pilot, the Cavalier required long and extensive training and was expensive to both purchase and to maintain. It wasn’t for everyone and was not produced in large numbers.

The Bonanza early safety record might have been bet ter if more of these pilots entered general aviation after the war.

Upon the pre-production introduction of the Bonanza through an extensive advertising campaign (see above) more than 1,400 paid pre-orders for the aeroplane flowed into Beechcra’s sales oices like a raging tide. Once production commenced the waiting list to purchase a Bonanza was in the many thousands.

Unfortunately, in those transitory and

awkward post-war years the Bonanza’s commercial success story was not at all the rule but the great exception. Encouraged by the early and enormous success of Beechcra’s Bonanza the other GA aeroplane manufactures breathlessly anticipated that they, too, might experience similar success and so they waited for the long- predicted hordes of customers to come crashing in and snatching up their aeroplanes. They waited, and waited and waited.

As virtually all of the rest of the GA industry lay substantially dormant, the Bonanza firmly and thoroughly established Beechcra as the cutting edge and the undisputed leading GA aircra manufacturer throughout the late 40’s and through 1950s.

From its introduction the Bonanza had been and was intended to be an instant status symbol, a totem upon which its owner might boldly announce apparent success and wealth. Very like Rolex,

Cadillac or Rolls-Royce, its exclusive high price and universally recognised quality put the Bonanza in an exclusive class which was highly attractive to businesses and individuals who wished to be seen and regarded as having the means to indulge themselves in such conspicuous, “goldhatted, high- bouncing” consumerism. And so it was that throughout the 50’s the Bonanza’s reputation and sales continued to soar and dominate the GA industry; its place at the top of the GA food chain remaining essentially unchallenged.

However, during the late 40’s and early 50’ the Bonanza did have a few notable ambitious would-be competitors such as the ultimate exotic, the civilianised P-51 fighter -- The Cavalier Mustang, the North American/Ryan Navion, a four place lowwing, all- metal GA aircra based, no less, upon the airframe of the P-51, the sleek and swi Meyers 200, the eicient but cosy Mooney MK-20, the classic Bellanca 14-13 Cruisair Senior and the 14-19-2 “230”

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North American /Ryan Navion. If it looks a lot like a four-place Mustang, it’s not a coincidence. Its spacious interior and good handling made and continues to make the Navion a popular choice. Around 3,00 0 were built and many are s till flying.

Meyer s 200. Similar in appearance and per formance to the Navion but without the Navion’s “Mustang” heritage, the excellent Meyers 200 nevertheless should have been but was not a commercial success.

The Globe Swift. Two place and aerobatic it was and is the classic “poor man’s” fighter aircraft. Many were sold, but being so small and lightweight, it was not really in competition with the Bonanza and was never a real challenge.

The Bellanc a Cruisemaster. A totally original design, fabric covered plywood struc ture with a wooden spar wing. Quirky in appearance and manufactured using old-school construction methods and materials, the otherwise excellently performing Bellanca was not a popular post-w ar choice.

Cruisemaster, and the sporty, aerobatic, two-place Globe/Temco Swi. However, as excellent as these aeroplanes were and are, not one of them, nor all of them together put an appreciable dent in the sales and popularity of Beechcra’s star and king of the single-engine GA hill.

PIPER STEPS UP TO THE PLATE

During Wold War II while it was perforce turning out militarized versions of the J-3 and, of all things, glider trainers created by cutting o a J-3’a engine and replacing it with a streamlined nose section, Piper Aircra did not entirely intend to rest upon the popularity of its J-3 Cub as its sole post-war product. The Comanche which was to come to light in 1958 was Piper’s first low-wing, all metal, single engine aeroplane, but it was not the first one of that type that they contemplated. At least two Piper designs intended to be produced aer the war were created in 1944, the PA-6 Sky Sedan and the PA-7 Skycoupe.

Originally named the PWA-6 and looking very like the Ryan Navion, the prototype Sky Sedan was a fabric-covered metal frame, four-place, low-wing, “family” oriented aeroplane. Originally designed to be powered by a 140 hp Franklin engine, the prototype was later actually powered by a 165 hp Continental E-165 engine (ironically the same engine as was used in the Bonanza). While a favourite of William Piper, the Sky Sedan’s performance with its relatively anaemic engine was predictably unexceptional and disappointing, so the project was laid to rest until aer the war. In 1947 the second and last Sky Sedan, named PA-6, was now all metal, was now powered by a more appropriate 205hp Continental E-185 engine, and had a one-piece windscreen.

Most painfully cognizant of the Beechcra Bonanza’s well-deserved success, by the middle 1950s Piper Aircra was anxious to produce its own modern, all metal, retractable gear, high performance single-engine aeroplane. Seeking to enter and to dominate the high-performance GA business aeroplane market and unseat the now long-term, highly successful Bonanza, Piper Aircra made ready to topple the King and to take its place on the GA highperformance business aeroplane throne.

To this end, what became the Piper

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PA-24 Comanche was developed to be “The Bonanza Killer”. It was Piper Aircra’s ambitious intention to not only put an end to the Bonanza’s reign, but to put Piper firmly on the map as GA’s leading and most advanced aircra manufacturer. Piper knew that to do all of this would require an exceptional aeroplane, one that was built and performed to the highest standards, was roomy and comfortable on long flights, had solid, stable, predictable handling and exhibited gentle and forgiving flight characteristics.

Of all, this last requirement was key. Piper, having analysed the Bonanza design was well-aware that as a trade-o for its outstanding performance, Beechcra had incorporated features in the Bonanza which compromised pitch and roll stability, C. G. loading, slow and departed flight regimes (stall/spin) and ease of flying, making their otherwise excellent aeroplane more than a bit if a handful for lowtime and less experienced pilots. Piper could clearly see the potential commercial benefit of creating a better handling and performing aircra using more modern techniques and knowledge, and was confident that their new aeroplane would be highly competitive and would deliver excellent performance without going down the same route of the Bonanza.

Another 1945 press release regarding the PA-6.

A 1945 advertisement to tes t the water as to how the public might react to the Sky Sedan. The performance claims therein are, well…a bit optimistic.

THE CRACK IN THE KING’S MIRROR

For all of its beauty, innovation, performance and commercial success the Bonanza, when Piper more closely looked upon it, showed that it possessed a number of serious design compromises which Piper believed were dubious at best and alarmingly dangerous at worst. Mr. Piper was convinced that he and his company had the ability to design and produce an equal or better performing aeroplane in every respect. By applying more advanced aerodynamics and with a stronger, better configured airframe, their new airplane would possess overall gentle and predictable handling as well as solid, high speed performance without compromise.

To be fair to Beechcra, by the time that Piper began to design the Comanche in 1957, the Bonanza design was then more than a decade old, and had fundamentally changed very little and was showing its age. Yes, over the years Beechcra

1947 Piper PA-6 Sk y Sedan planned advertisement photo. This is the second and the last one to be built. Note: GA aircr aft adver tising then and today makes all aeroplanes look roomier than they may actually be by placing in the cock pit the smallest available passengers it can find for photographs. Note the emaciated looking pilot and the miniature children.

Piper PA-7 Skycoupe looking like something from the film “H. G. Well’s Things to Come”.

The only Skycoupe ever built. An interesting and futuristic design, “It didn’t fly worth a damn!” said Pug Piper of it.

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THE HENRY FORD OF AVIATION

illiam T. Piper was an extraordinary person.

dream perhaps, that the light, private aeroplane would become as ubiquitous in American society as had the automobile. Merely having an idea (or a dream) was not; however, what made Mr. Piper extraordinary. Mr. Piper was, one might reasonably say, a stubborn man. Once this idea had firmly situated itself in his imagination, he went to work to make it become a reality, and through fire and flood he never ceased applying all of his being towards that end.

aeroplane manufacturing business until 1929 just as the Great Depression was about to commence. He was not an engineer nor even at that time a pilot (he did eventually obtain his private pilot’s licence in 1941 at the age of 60). Up until then Piper had been a successful crude petroleum developer operating a number of lucrative oil wells in and around Bradford, Pennsylvania. Piper only became aware of the Taylor Aircra Company and its economic failure by accident in that he was one of a number of successful local businessmen who were seeking to shore up failing businesses in Bradford so as maintain and foster local industry.

He had an idea, a

Piper did not enter the

In 1929 Piper, seeing that the Taylor company was about to drown he purchased $600 worth of Taylor Co.’s then worthless stock. Unfortunately this salvatory investment was insuicient to stave o incipient commercial disaster and Taylor went bankrupt in 1931. Piper then bought the land and buildings owned by Taylor Co. at the bankruptcy sale for $761.00 and permitted Taylor to use the facilities rentfree. Piper became the treasurer and a board member of the new Taylor Aircra Company with C. G. Taylor the President in charge of engineering. Piper reserved for himself the responsibility to raise capitol for the new company and was, appropriately, the chief salesman.

Aer a few abortive and tentative attempts to re-invigorate Taylor Aircra Piper persuaded C. G. Taylor to design an entirely new and far simpler aeroplane than the old complex Taylor “Chummy” which was expensive to build and, accordingly, carried too high a sales price. That new aeroplane eventually became the J-3 Cub.

There are many similarities between Henry Ford and William T. Piper. Both men recognized early in their careers that there was an untapped market for their particular products that could be opened wide if an aordable

and reliable product became available. They both understood that a good, solid but no-frills automobile/aeroplane could be designed and so economically manufactured that it could be oered at a price that most Americans could aord. Like Ford, Piper also implemented a kind of assembly line to produce aeroplanes, cannibalising an old, broken carnival Ferris wheel and parts from an old barn.

Despite his eorts to streamline the Piper aircra assembly process, the hard fact is that aeroplanes require far more skilled hands-on work to build that do automobiles. Accordingly, Piper needed a fairly large, well trained work force in his factory. By 1940, with America still deep in the throes of the Depression, he employed more than 1,000 men and women full time, average age 23, to build Piper aeroplanes.

In the United States in the late 1930’s and early 1940’s the volume of all light aircra sales did not even approach one- hundredth the volume of sales of automobiles and Piper Aircra Co.’s share of the aviation business was, of course, only a percentage of that. Piper could only aord to pay his employees a maximum wage of .40¢ per hour while the contemporary automobile worker made as much as .93¢ per hour. To keep

his employees he oered them incentives, as had Henry Ford in his early days.

He oered his factory workers the opportunity to rent a Piper Cub to take lessons in or to just to fly if they already were pilots for no more than the cost of the gasoline and oil, which equalled approximately $1.00 per hour. In an article about William T. Piper Fortune magazine said, ‘’He could tap an unlimited reservoir of smart, eager boys, so crazy about flying that they were willing to work for nothing if they could only start their days o by laying hands on a Cub wing.” As a sales incentive Piper also oered any J-3 purchaser eight hours free flight instruction. As a kind of gentle “payola” he extended this to the media as well, oering free flight training to writers who would help to expose the public to Piper’s aeroplanes.

Like Ford, Piper had a firm conception of what his company’s economic place was and how he could use it to foster Piper sales. Regarding the vast economic Depression that was overtaking the world in the 1930s Piper later said, ‘’Everyone who was still flying was starved into using Cubs.’’ Also like Ford, Piper chose a single colour for his aeroplanes. Ford had chosen black, Piper chose yellow.

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F-4U-1 Corsair “Birdcage” landing during aircraft carrier trials on the USSSangamon on 25 September 1942. With flaps full down the left wing has suddenly stalled befor e the right wing, a trait common to the NACA 23000 series airfoil which was incorporated in this aeroplane. (notice that the pilot has applied full right rudder to try to prevent going over the side. He has correctly applied no right aileron because trying to pick up a wing with aileron when in a stalled condition in an aeroplane of this class is usually a fatal mist ake.)

had made a scant few improvements and changes to the original Model 35, specifically with regard to higher performance specs created by simply increasing horsepower, but the Bonanza of the middle to late 50’s was essentially and substantially the same as the 1946 model.

The 1957 Bonanza “H” was the first of the high-powered Bonanzas. Except for the marked increase in horsepower it, too, remained essentially the same as the 1947 Model 35. It has the Model 35’s highly tapered wing with an area of only 177.6 sq. . to liing its 3,050 lb. gross weight (aer various supplemental type certificates (S T Cs). This puts its wing loading (maximum gross weight divided by wing area) at 17.17 lbs. /sq. ., which was then the highest wing loading for a single-engine GA aeroplane of its class and size (excepting the Cavalier which was, of course, a civilianized P-51). As a comparison, a lighter Piper Comanche at 2,800 lbs. gross weight with a wing area of 178 sq. . has a lower wing loading of 15.7 lbs. /sq. .

That the Bonanza’s wing was smaller than perhaps it ought to have been was a deliberate design choice. The shorter span and less wetted area of the Bonanza’s wing permitted greater airspeed but, of course, greatly increased the Bonanza’s wing loading. Such airspeed gains as may be had thereby come at the expense of ease of

flying for less experienced pilots and more importantly, of safety for all pilots.

An aeroplane with a higher wing loading is more critical of less- than- expert piloting techniques, particularly at lower airspeeds and is more likely to literally turn and bite if not handled expertly and well. Aircra with high wing loadings are more likely to suddenly enter an accelerated stall (reaching critical Alpha) even whilst airspeed is well above normal stalling airspeed (Vso) by turning too sharply and/or suddenly applying positive pitch. Also, a high wing loaded aircra is usually more likely to spin out of an ordinary stall and more likely to spin out of an uncoordinated turn at low airspeeds.

While Beechcra actually experimented with a laminar flow airfoil on early Bonanza prototypes, it ultimately and conservatively selected the old NACA 23000 series airfoils (wing root - 23016.5, wingtip - 23012) for the Bonanza. The NACA 23000 series airfoil dates back to 1935 and was very widely used throughout that and the following decade. The U. S. Navy F-4U Corsair and F-8-F Bearcat incorporate this airfoil.

While the NACA 23000 series airfoils are reasonably useful for higher airspeed applications provided appropriate power is available, it does not produce as predictable and benign departed

flight characteristics as the Comanche’s even faster and far more modern, scientifically designed NACA 64(2)-A215 laminar airfoil. This is partially but primarily because the 23000 series of airfoils exhibit a rapid Cl (Coeicient of Li) decline when approaching stall Alpha (angle of attack) and thereby are likely to produce a rather abrupt stall/spin.

Precipitous le wing drop during landing was a serious and dangerous problem for the F-4U-1 Corsair which, like the Bonanza, incorporates a NACA 23000 series airfoil. This and other problems initially disqualified the Corsair for U.S. Navy aircra carrier duty (although the Royal Navy, desperate for a real, purpose-designed carrier aeroplane, gladly accepted it even with its serious low speed handling flaws in June 1943 as the “Corsair I.”)

Accordingly, if for example when flying an aeroplane with this airfoil such as the Bonanza a pilot should overshoot his turn to final, pulling harder to tighten the turn may result in a sudden stall with an accompanying sharp wing drop or possibly an over- the- top spin. Even during a normal landing with full flaps, getting too slow in a Bonanza can result in a sudden wing drop, etc. Both of these scenarios have resulted in numerous fatal accidents during landings in the Bonanza.

The Bonanza’s V-tail, so designed to

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reduce drag by eliminating one entire tail surface and to look very cool has its advantages and also some apparent detriments. In addition to its distinctive appearance and even though each of the two surfaces of the V-tail are larger in both span and chord than any of the surfaces of a comparable three - surface conventional cruciform tail, Beech believed that the V-tail would save weight and possibly create a bit less drag. While not hard scientific fact, perhaps the V-tail does help Bonanzas fly a bit faster, but it is reported by many pilots to be not as stable at slower airspeeds as a conventional tail. Some pilots have reported that they “ran out of rudder” in strong cross-wind landings in a Bonanza. This phenomenon might have actually been caused by the Bonanza’s yoke and rudder pedals bungee interconnect system designed to enable coordinated turns with the yoke only. Some pilots have reported that the V-tail’s stall/spin characteristics are, to put it politely, not as benign as those of aeroplanes with a conventional tail; although this may be more due to the Bonanza’s high Alpha- sensitive airfoil. As to V-Tail characteristics, opinions may vary.

Wind-tunnel tests later showed that the Bonanza’s V-tail was also not structurally suiciently robust and it would become the focus of inquiry with regard to fatal accidents involving airframe failure in flight.

Some believe that Beechcra’s original design philosophy regarding the Bonanza, i.e. that since it would be largely flown by highly experienced, professional pilots that its flight characteristics need not lean towards ease of flying for low-time pilots, came home to roost as the number reports of a number of structure-related accidents began to toll during the 1950s. It was discovered that in virtually all of these accidents where the airframe had failed in flight that the probable cause was attributable to either the pilot’s loss of control and/ or the pilot’s over control upon attempting a correction. Most of these accidents occurred whilst a relatively inexperienced pilot was hand-flying the Bonanza in IFR conditions and in many instances while the aeroplane was loaded so that the C. G. (centre of gravity) was chock up against or beyond its maximum permissible a location.

A very serious V-tail Bonanza characteristic is that it is quite sensitive to

Compare how the Comanche’s main wing is set further back, making it more suitable for carr ying heav y aft loads while staying within safe centre of gravity limits.

You can see, by comparison, the Comanche’s wing is 1-2 feet further back.

weight and balance/C.G. considerations. Early V-tail Bonanza’s (Model 35 through 35J) have a rather narrow C. G. range of

9.2”; i.e., between 76” and 85.2” a of the horizontal reference datum line. As a comparison the 1958 Comanche 250’s C. G. range is 12.5”; that is, between

80.5” and 93.0” of the datum line. This indicates the Comanche 250 may be loaded over a far greater distance a of the datum line than a Bonanza 35H. Accordingly, it is particularly easy to inadvertently load an early V-Tail Bonanza a of its rear limits.

It is not well known, but all V-tail Bonanzas, from the first until almost the last, have a down spring connected to the elevator control system which imparts a constant forward push on the control wheel. The elevator trim could override this but it is always “on” and cannot be turned “o”. An elevator control down spring is a

very unusual item for a GA aeroplane. That Beechcra felt that it was necessary to install this on the Bonanza speaks volumes about the V-Tail design. It also makes one wonder if Beechcra knew full well that its speedy little aeroplane had some serious control issues at low airspeeds which additionally would be greatly exacerbated by a too-a C. G. loading. With this revelation one may justly wonder how the V-tail Bonanza originally passed and continued to pass airworthiness muster with the CAA (Civil Aviation Administration) and later the FAA (Federal Aviation Administration).

Ironically, it is the Bonanza’s greatest characteristic, its aerodynamic cleanliness, that has been the cause of a good deal of the peril experienced by low-time Bonanza pilots who have recently transitioned to the Bonanza from lower-performance aircra. Unlike slower fixed gear airplanes, higher performance, streamlined,

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retractable-gear airplanes will pick up speed at an alarming rate by comparison when the nose is lowered in flight. Once airspeed is well-into the airspeed indicator’s yellow arc and certainly if it is past the red line, any attempt to level the wings and/or bring the nose back up which is not executed with extreme delicacy and expertise (and in many instances even when performed so) will result in exceeding design G-load, over-stressing and ultimately distorting the wings and/or the V-tail which then is rendered useless to positively alter the aircra’s pitch so as to regain level flight causing the wings to fail and resulting in the aircra breaking up in flight.

Essentially, it requires very gentle rearward yoke pressure and some good fortune to safely pull an over-speeding Bonanza back to level flight and to slow it down before something breaks. Too much rearward pressure when flying too fast and a wing or two “may assume an independent flight path from the rest of the airframe” (credit to Darryl H.). Combine this trait with an obscured or not visible horizon situation or in actual IFR conditions and where the unstable roll axis causes one of the wings to drop as it will eventually do if not strictly attended to, you have the alltoo-common deadly spiral dive. To make things even worse, if the aircra is loaded near, at or beyond its maximum permissible a C. G., which as said is all-too-easy to do in a V-tail Bonanza, elevator response becomes considerably more sensitive and catastrophic over- control in an attempted pull out becomes even more likely.

Assembling and analysing all of the information at hand over more than a decade the CAB determined that a VFR pilot hand-flying the V-tail Bonanza in IFR conditions was virtually certain to quickly enter into a spiral dive and ultimately suer a fatal crash.

ABOUT SPIRAL DIVES…

On 16 July 1999, John Kennedy Jr., was flying his new Piper Saratoga II HP, the 300 hp retractable undercarriage Cherokee Six from Essex County Airport, New Jersey to Martha’s Vineyard on a hot and hazy summer’s evening with his wife and her sister also on board. He had only 310 total flying hours and only 36 hours in this demanding, high-performance aeroplane, some instrument training but no instrument

Spiral Dive

ticket. At some point over the water he lost sight of the horizon and suered from spatial disorientation. Inevitably, one of the Saratoga’s wings went down and the nose dropped. As airspeed wildly increased he tried to pull up nose to slow the aeroplane but merely tightened the spiral until the Saratoga hit the water.

Many Bonanza pilots who were not professionals and those who were not used toflying such a clean airplane which was additionally unstable in roll found the aeroplane to be more than a safe handful.

In the 1950s and early 1960s legal IFR flying activity by GA pilots was very rare. The IFR system was then still fairly crude and not so widely available as it is today. Additionally, in those days very few GA and even ex-military pilots had instrument ratings or had received any serious IFR training. Accordingly, the vast majority of Bonanza pilots were strictly VFR rated and this was what got so many of them into serious trouble.

As time passed and more and more V-tail Bonanza in-flight structural breakups were reported, in 1989 Beechcra performed a series of wind-tunnel and other practical tests on the V-tail Bonanza. It was discovered that as designed the sensitive V-tail could not be relied upon to permit safe pilot application in the pitch axis even when the aeroplane was flown within and at one corner of its certified flight performance envelope. This could result in structural failure of the V-tail which would cause the aircra to quickly exceed its safe airspeed limit and break up in flight.

V-TAIL AND C.G.

hen the C.G. is too far a in any aeroplane the pilot will experi-

is able to takeo without mishap, overly sensitive elevator control at cruising airspeeds and a sharp deficiency of elevator control at low airspeeds, such as when

taking o and landing.

predecessor to the NTSB - National Transportation Safety Board) accident records show that a too far a C. G. was tragically all-too-oen the probable cause of fatal accidents involving early V-tail Bonanza’s. They found that in many instances an inexperienced or negligent V-tail Bonanza pilot loaded the aeroplane even slightly too far a and thereaer experienced serious, oen fatal lowairspeed pitch control deficiency and/ or pitch over- control at high airspeeds leading to structural failure.

that modern, cruciform- tail Bonanza (which is actually the Debonair) have very generous horizontal weight and balance envelopes and do not suer from the above mentioned condition.

considered to be rather light and sensitive in normal operations, and while the aeroplane is only modestly stable in the pitch axis (constant hunting whilst cruising), it is far less stable in the roll axis.

Reinforcements, stieners and cus were applied to the V-tail which caused Beechcra a good deal of angst as this was proof positive that the Bonanza’s original design which was produced for 35 years was not adequate and was a contributing cause of many fatal accidents.

In 1960, Beechcra produced the Debonair, a slightly dressed- down Bonanza with a conventional cruciform tail. Many pilots report that the Debonair is a better flying aeroplane than the Bonanza at all times and particularly when in turbulence and that it does not tend to “hunt” in pitch during normal cruise as do V- tail Bonanzas. Most significantly, the conventional tail Debonair’s fatal accident record is 24 times better than the V-tail Bonanza’s. Because of all of the above in 1982 Beechcra stopped production of the V-tail Bonanza, dropped the Debonair model

ence, assuming that he or she

CAB (Civil Aeronautics Board the

It should be mentioned in all fairness

The early V-tail Bonanza’s controls are

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Mooney M-20 with German registration on an airfield in Germany

and name, and continued to produce and develop what is, in fact the conventional tail Debonair, now calling it Bonanza.

To be fair, much of what caused lowtime pilots to have a very high rate of fatal accidents when flying the Bonanza was, as with John Kennedy, Jr. in the similarly high - performance Saratoga, more due to

1958 Piper Comanche 250

their inexperience with high-performance aircra than any fault of the thoroughbred, high - spirited Beechcra. However, because of its extremely high accident rate, mostly while being flown by private pilots without instrument ratings and no more than 300-400 hours total flight time, the Bonanza became popularly known as

the “The Doctor Killer”, referring to the many well-o physicians who could aord to purchase one, but who lacked suicient flight time and expertise to fly it safely, and who thereby came to a tragic end.

Additionally, as said, there have been a rash of Bonanza structural failure accidents having to do with wings being pulled o aer unintended over-speeding and too abrupt pull outs.

ENTER THE COMANCHE

William T. Piper knew that in seeking to enter the high-performance, single-engine business aeroplane market and challenging the iconic Bonanza that he was he was taking on a very tough, commercially risky task. As mentioned, from the company’s inception, all production Piper aircra had been high wing, fabric covered aircra. However, by the mid-1950’s Piper was already planning for the future and making changes towards the production of a more modern fleet. Indicative of this, in 1954, in a single dramatic and bold

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move, Piper splashed into the modern GA market with its first low-wing, retractable undercarriage, all- metal aeroplane -- the four-seat, twin-engine PA-23 Apache which was the first Piper to be named for a Native American tribe.

Closely following his original concept of simplicity which had created the venerable “Cub”, Piper had his engineers design a simple, no frills and relatively inexpensive but well-performing light twin, the Piper Apache. It quickly proved to be highly popular and, among other things, filled the niche as an ideal and economical multiengine trainer and well as a personal touring aeroplane with the ostensible “safely factor” of a second engine (some pessimists say that having two engines simply doubles your chances of an engine failure, but that is a minority opinion).

Besides enjoying a solid commercial success, in the course of manufacturing the Apache, Piper Aircra gained experience and confidence with regard to the particular methods and ways of modern all-metal aircra production. The days of the highly labour- intensive fabric covered tube frame aircra designs such as the Tri-Pacer were quickly waning and with success of the all metal Apache Piper saw that the way was now clear for more of the same.

During the four years aer the Apache was introduced, Piper was actively planning to achieve its program reguarding taking the Bonanza’s place in the highperformance GA market. There is more than one popular, possibly apocryphal version of the genesis of the Comanche design, one of them is – Looking around for a suitable high performance design, it happened that a Mooney M-20, which had been introduced in 1955 and which was known for getting very high cruise numbers (149KTS top – 143KTS at 75% power at 7,000’) for its 150 hp (110 kW) Lycoming O

-320 engine,, was temporarily hangered at Piper’s Lock Haven PA factory. As the story goes, William T. Piper and his engineers gave it a long, close look, measured every aspect of it and used what they found to come up with the Comanche design.

Another version goes like this -- William T. Piper (or Howard “Pug” Piper, William’s son, depending upon from whom you are hearing the story) approached designer Al Mooney with an oer to buy the M-20

design which would, with some modifications, thereaer become the new Piper aeroplane. However, Al Mooney refused to sell, but as an alternative Mooney oered to design a brand-new aeroplane for Piper to their specifications. According to this version of the story, the specific design features that Piper asked Mooney to incorporate were: high cruise performance for available power (a Mooney trademark); a relatively simple, light airframe and components which would be economical to manufacture permitting Piper to greatly undercut the Bonanza’s notoriously high price; a more spacious and comfortable cabin than that of both the rather short and narrow M-20 and even of the fairly capacious Bonanza; and, especially a new, uniquely modern appearance which would suggest speed and eiciency to the aeroplane- buying public.

Whatever the truth of the matter may be (and I lean towards the second story) there is no question that the final Comanche design and the M-20 share many features. Accordingly, it appears more likely that Al Mooney and “Pug” Piper, who was in charge of the development of the new Piper aeroplane, cooperated to complete the final design of what was to be Piper Aircra’s first all-metal, low- wing, singleengine aeroplane.

To foster the “jet-age” sales concept the Comanche’s design implemented was what was then an innovative swept-back, jet-like vertical fin and rudder, the first one of its kind to appear on a mass-produced GA aeroplane. This design feature was something of an inside joke as it simply reversed Mooney’s signature forward sweeping tail.

The question always asked about swept tails is whether with regard to an aeroplane that flies very far below trans-sonic or supersonic airspeeds does the application of a swept tail increase airspeed? With the Cessnas that changed to swept tails at least there was some means to compare the two configurations. In the instance of the Cessnas the answer is that where all other things are equal; no, there is no measurable increase in airspeed,

Unlike the Cessnas, there is no way to compare a straight- tailed Comanche with a swept tail version, so there may be no definitive answer forthcoming. However,

taking the Cessna example into consideration, the answer is most likely that the swept tail on the Comanche does not cause any increase in airspeed. However, it sure does look nice -- and fast.

Other innovative design features for a GA aeroplane incorporated into the Comanche’s design are the single- piece, all- flying stabilator with anti-servo tab; an all metal wing with a metal spar (1950’s M-20s had fabric covered wings with a wooden wing spar and fabric covered wooden tail surfaces); and an NACA 64(2)A215 laminar airfoil similar to that of the North American P-51 “Mustang” which airfoil was designed to permit the highest possible cruising airspeed for available power. The Comanche’s wing has five degrees of dihedral for good lateral stability while still retaining excellent roll rate.

The “laminar flow” airfoil is the invention of Eastman Jacobs, an aerodymicist who worked for NACA (National Advisory Committee for Aeronautics, the predecessor to today’s NASA- National Aeronautics and Space Administration) in the 1930’s. It was well- known by then that the thin layer of air closest to the surface of an airfoil, called the “boundary layer”, was highly significant with regard to the wing’s production of li and influenced the way that high and low pressure areas were distributed as they moved from the wing’s leading to trailing edge. Jacob’s conception was that if the boundary layer could be made to adhere to and remain parallel to the airfoil’s surface for a longer distance from the leading edge of the wing than the common airfoils being used, drag would be markedly reduced. Through wind-tunnel tests Jacobs determined that the thickest part of the airfoil where the local pressure was lowest best sustained an attached and parallel laminar flow boundary layer, but that as the airfoil became thinner and local pressure became higher the usual drag-producing vortexes and eddies in the boundary layer began to arise, eventually becoming turbulent and producing a good deal of drag. Jacobs realised that if the thickest part of the airfoil was moved back from its usual 25-35% position from the leading edge to, say, the 40-50% position, that a good deal of the drag produced by the long rear section of turbulent boundary layer could be avoided.

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Additionally, the following is extracted (and slightly edited) from the A2A Cherokee 180 Manual as it applies equally to the Comanche:

“Just a quick word or two about airfoils and what a “laminar flow airfoil” is. The wing’s airfoil is its cross section shape from leading to trailing edge and current aerodynamic theory holds that the airfoil is primarily and most importantly an air diverter. Among other things, the airfoil diverts the air through which an aeroplane’s wing travels downwards at the wing’s trailing edge so that li may be generated (see Newton’s Third Law of Motion). In order to do this the “boundary layer”, which is the very thin, viscous layer of air closest to the surface of the wing, must adhere to the wing and not become turbulent or detach from the surface of the wing before it can be diverted downward at the trialing edge. There are many theories of li, some traditional, some imaginative and seemingly intuitive. However, in recent years most of the traditional theories have been discredited as they were found to be flawed, entirely improbable or simply wrong as aeronautical knowledge and understanding has progressed. It is most likely that there are numerous ways in which a wing produces li. The airfoil as a downwash “air diverter” at the trailing edge is and has for a while been what this writer thinks is the most probable correct theory. Of course, the true scientific mind must always be open to new facts and disclosures. This writer awaits with great interest what is yet to be discovered.

Also, a smooth and adherent boundary layer produces minimum pressure and/or parasite drag enabling the aeroplane to

Note that the laminar flow airfoil’s thickest point is farther back from the leading edge than the ordinary airfoil’s.

fly faster for any given amount of power. Slight micro-turbulation in the boundary layer actually increases its adherence to the surface of the wing; but, when this turbulation becomes more severe and becomes a turbulent flow, li is reduced and pressure drag increases. If this turbulence becomes too severe, which typically happens at critical positive Alpha, the turbulent boundary layer detaches from the surface of the wing creating random eddies and vortices causing considerable parasite and pressure drag to be produced. Upon boundary layer flow separation from the surface of the wing the former downward diverted air flow ceases and, concurrently, the wing ceases to generate li. This is the “stall”.

An airfoil designed to produce maximum uninterrupted, adhesive boundary layer flow at the surface of the wing and minimum drag by moving the thickest part of the airfoil back to the 40-50% point is called a “laminar flow airfoil”.

NACA NUMEROLOGY

The first number, “6”, of NACA 64(2)-A215 (the Comanche’s airfoil) indicates that this is a NACA “6-series” airfoil. The second number, “4”, indicates the position in percentage x 10 of the chord (leading to trailing edge) where minimum pressure occurs — here indicating the 40% chord position. Minimum pressure usually occurs at the thickest part of the airfoil. The subscript “2” indicates that this airfoil’s Cd (coeicient of drag) approximates its minimum value between plus or minus 0.2 of the airfoil’s design Cl. (coeicient of li). The NACA 65(9)-415 airfoil which was used for the Cherokee is a later refinement of the

Comanche’s NACA 64(2)-415. The only significant dierence between the Cherokee’s airfoil and the Comanche’s is that in the Cherokee’s airfoil the Cd approximates its minimum value between plus or minus

0.9 of the airfoil’s design Cl while the Comanche’s Cd approximates its minimum value between plus or minus 0.2 of the airfoil’s design Cl. The next number “2” indicates the li coeicient in tenths; here, 0.2. The last two numbers, “15”, indicate the wing’s maximum thickness as a percentage of the chord; here, 15% of the chord. A laminar flow airfoil is typically designed so that its thickest point is usually at approximately 40-50% of the chord. A normal airfoil’s (Bonanza’s) thickest point is usually at approximately 25- 33% of the chord. The laminar flow airfoil shape combined with a very smooth wing surface best promotes a smooth and adherent boundary layer fostering higher airspeed capability.

COMANCHE DESIGN

The North American P-51 “Mustang” was the world’s first purely mathematically designed aeroplane and its wing was the first to be deliberately designed with a “laminar flow” airfoil. However, even a very slight ripple or bump in or on the surface of the wing will prevent the true laminar flow eect. Despite all good intentions what with numerous hatches and doors and such for the maintenance of guns, reloading of ammunition and the like the P-51’s wing surface as manufactured is not suiciently smooth and uninterrupted nor was it optimally built or suiciently maintained to be clean in the field to promote true laminar flow. The Comanche’s wing surface, however, is actually far smoother and if kept scrupulously clean, promotes a stable, adherent boundary layer very well. A salient characteristic of the Comanche’s airfoil is that it has a fairly flat Cd curve right up to the stall and thereby looses li very slowly as the stall is approached, although not to the extent as does the Cherokee with its slightly more advanced laminar flow shape. Also, the Cherokee’s airfoil does not possess a single critical angle of attack (positive Alpha) at which it will stall. The Comanche’s NACA 64(2)-415 airfoil flies within a fairly broad range of positive Alpha (limited only by the wing’s aspect ratio as discussed below) and does

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not break very sharply at the stall unless very aggressively forced into an extreme positive Alpha condition called a “deep stall”. Spins are likewise diicult to enter unless aggressively pursued.

Another design feature that is an innovation, at least and certainly for Piper in the late 1950s, is the Comanche’s high aspect ratio (AR) wing at 7.53 (see calculations below). The AR is the mean chord (measured from the leading to the trailing edge) divided into the overall wingspan (which includes the width of the fuselage). The average AR for GA single –engine aeroplanes is between 5 and 6. That is the chord is 1/5th or 1/6th the span. AR lower than 5 is considered to be in the low AR range and above 6 to be in the high range.

For wings that are tapered (not rectangular) as is the Comanche’s wing, the AR is calculated as the square of the span divided by the wing area. AR= span (sq.)/ area. The Comanche’s wingspan is 36 .

and its area is 172 sq. .

Span squared divided by the wing’s

area = aspect ratio

Span- 36 (sq.) =1,296 wing area=172;

accordingly, 1,296/172= 7.53.

This is a rather large AR which gives the

Comanche’s wing specific characteristics.

A higher AR wing is more eicient than a wing of the same area but with a lower AR for the following reasons:

As discussed above li is primarily a product of downwash at the trailing edge. Where there is more clear trailing edge available to produce downwash, more li will be produced.

The wingtip and its proximate area produces little to no li and produces a strong drag - producing vortex caused by the high air pressure below the wing swirling into the lower air pressure above the wing, all of which is called “tip eect”. The force and depth tip eect into the wingspan on wings of approximately the same area (but

not necessarily of the same AR) is roughly equal.

Accordingly, the greater the distance the tip of the wing and the resulting tip eect is from the wing root the greater the clear span of li -producing trailing edge and lesser the relative tip eect on the entire wing.

As shown, the tip eect is approximately the same regardless of the length of otherwise similar wings. Accordingly, the higher AR wing is less negatively aected by tip eect than the lower AR wing increasing the eiciency of the higher AR wing.

Additionally, as the AR increases the CL increases and less Angle of Attack (Alpha) is required to produce li, increasing eiciency once again.

However, the graph above also indicates that higher AR wings stall at a lower Alpha. This means that the higher the AR of the wing is the less useable positive Alpha it has.

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Radio controlled Cur tiss Robin model popular for sailplane towing. Note the average aspect ratio of the wing.

A PRACTICAL DEMONSTRATION OF THE EFFECTS OF ASPECT RATIO

This particular principle of aspect ratio was illustrated to me in an interesting and clearly demonstrative way one day a few years ago when I was visiting some friends at a local radio-controlled (R/C) model aeroplane field. Some of the pilots had large un-powered sailplanes which they would get up to thermal (where the air has natural li) altitude by having another pilot aero-tow it. The sailplane had a radiocontrolled towline release mechanism when the sailplane pilot was high enough.

The tow aeroplane was a very large and sturdy, a sort- of- scale Curtiss Robin with a 96” (8’) wing and a powerful 62cc gasoline engine with a 22x10” propeller. The AR of the Robin’s wing was average, the average chord approximately 17 ½”, 5.5 of the span. However, the sailplanes were all between 4 meters (13.12’) and 5 metres (16.40’) and had very high ARs of 20-30; that is, their very narrow chords were between 6 and 7½”.

The tow pilot was a very good R/C pilot but he had no previous experience towing sailplanes. One of the larger sailplanes, a gorgeous 5 metre Discus, hooked up to the 30 foot towline and o they went without incident, for a few minutes anyway. That majestic sailplane being towed by the powerful Robin looked very like a full-scale operation. They settled into a nice, smooth

5- Metre Discus R/C sailplane. Note the extremely high aspect ratio of the wing.

coordinated flight, constantly communicating to each other and then the tow pilot began the climb to altitude. He climbed at his usual angle at full power with plenty of airspeed for the sailplane. However, a soon as the Robin pitched up and began to climb the sailplane behind it began to stall and the tow line pulled down sharply on the tail of the Robin which had been climbing with no trouble.

Baled, the tow pilot levelled o and the sailplane began to fly again. Once again the tow pilot began his usual climb and once again the sailplane stalled out behind the tow aeroplane and once again the tow pilot levelled o. The sailplane pilot and the tow pilot were in a conversation as to what was going on. The tow pilot said that he was intentionally climbing at a good airspeed to prevent the sailplane from stalling, and in any event, the sailplane’s stall speed was far lower than the heavy Robin’s.

Watching carefully I thought that I understood what was happening and I suggested to them that the tow pilot climb at more moderate angle. He did this and he was then able to tow the sailplane up until it was very small. The sailplane pilot then disengaged, went looking for thermal li and the tow aeroplane came down for a landing.

Aer the sailplane had flown for at least a half-hour, the sailplane pilot brought it down for a graceful landing. The tow pilot

and sailplane pilot asked me what had happened and why the normal climb did not work and the moderate climb worked. I explained about high and low ARs and stall Alphas, etc. The tow aeroplane with its average AR could climb at fairly high Alpha while the sailplane could only climb at a fairly low Alpha. Once the tow aeroplane reduced its Alpha the sailplane could climb behind it with no trouble.

In its time, the new Comanche was overall a very aerodynamically clean design with the exception of the engine cowling intake openings which are, typical of similar aircra of the late 1950’s, unnecessarily large, creating unnecessary drag from excessive air entering the cowling. This ineicient, airspeed robbing cowling design is also found on the Mooney M20 and many GA aircra designs of the late 50s and 60s, including to a slightly lesser degree, the Bonanza.

While a trailing link style undercarriage, found in both Mooney and Beechcra aircra, is a pilot- friendly and well-proved design, Piper’s engineers, ever vigilant about keeping down the Comanche’s selling price, designed a simpler, straight, oleo tube undercarriage for the Comanche. As aircra incorporating this kind of less forgiving undercarriage require more refined piloting skills to make so landings, Comanche pilots who can do so justly own some bragging rights over Mooney and

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Beechcra pilots.

Full, dual controls (except initially for right toe brakes) as in all previous Piper aircra were incorporated into the Comanche as well. Piper believed that this would be would be better received than the Bonanza’s single throw-over control column which was a curious throwback to the 1930/40’s era Beechcra Staggerwing and other aircra of that era, and which was oen popularly criticised. Of course, Beechcra did not anticipate that the Bonanza would be used as a trainer and felt that a single throw-over wheel, leaving the front passenger seat completely unobstructed was the best design for a business aeroplane. BTW, the throw-over wheel makes getting checked out in a Bonanza with this feature a bit of a chore.

For the sake of further simplicity and manufacturing familiarity, the flaps would be manually operated by a central flap handle as in the Tri-Pacer, the elevator trim likewise operated by an overhead horizontal crank (see below), and toe brakes would be available only on the pilot’s rudder pedals (although a kit for retro-fitting a second set of toe brakes would soon be made available). The decision that the first new Comanche would be powered by the 180 hp (134 kW) Lycoming O-360A1A engine was a curious one, given that the 1957 H35 Bonanza with which Piper was competing had a 240 hp Continental O-470-G engine giving the Bonanza a Beechcra “published” 75% cruise of 165kts at 7,500’.

An interesting but little known fact about the design of the Comanche is that Piper used a few common automotive items on the aeroplane one may suppose for economic reasons and perhaps in order to make it more customer- friendly.

One of these items is the interior door handle. The 1958-60 Comanche handles appeared to identical to those used in 195666 Studebakers, later Comanches used interior door handles from the 1967 Ford Falcon or Fairlane. Another, later Comanche door handle is from Volkswagon and is a small handle that is recessed into the door and is pulled back to open.

Not only did Piper apparently use automotive parts for interior door handles, they also used a 1956 Studebaker window crank for the overhead elevator trim control on earlier Comanches, before the

elevator trim control was moved to the floor between the seats.

By January 1958 the first Piper PA-24180-Comanche was delivered to the public. Its price was a rather modest (for an aeroplane of this quality) $14,500.00 ($118,708.84 in 2015), but it was not the aeroplane that Piper knew it had to build to compete with the more powerful (240 hp) Bonanza. The Comanche 180’s useful load was a respectable and competitive 1,020 lbs., actually 166 lbs. greater than the Bonanza H35, and its cruising speed at 75% at 8,000’ was 139kts which is excellent for a 180 hp aeroplane, but it was not nearly fast enough to seriously compete with the Bonanza.

CATCHING THE BONANZA

At all times fully aware of the 240 hp H35, Piper began to immediately test the installation of a 250 hp Lycoming O-540 engine in the Comanche. The PA-24-250 was introduced in April 1958 and had a 75% cruise speed at 7,500’ of 160 KTS and a useful load of 1,110 lbs., now 246 lbs. greater than the H35.

As Piper had so meticulously planned, the Comanche 250’s 1958 basic price of $21,250.00 ($173,969.85 in 2015) was just a bit less than the basic price of a contemporary Beechcra H35 which was $22,650.00 ($185,431.40 in 2015). One might truly say that even if the 1958 Comanche 250 was slightly slower than the Bonanza H35 according to Beechcra’s claims (and this is definitely not necessarily so), the dierence in cost between the two aeroplanes certainly did not justify the Bonanza’s higher price.

Given its very competitive and excellent specs and distinct advantages the choice of the Comanche 250 was (and still is), for most prospective owners a “no brainer’. What the less expensive Comanche 250

The top airfoil is almost identical to the Bonanza’s root airfoil. The centre airfoil is close to the Comanche’s airfoil and is of a laminar flow design. The bottom airfoil is a more extreme laminar flow airfoil, most often seen on military jet aircraf t.

oers over the Bonanza H35 is a higher useful load, a wider, more comfortable cabin, dual controls and, most importantly, more stable handing, particularly at lower airspeeds and without the need for a down spring on the elevator control system! What William Piper had wanted from the Comanche and what he got was a high performance aeroplane with such solid aerodynamics that even low time pilots could confidently move up to and safely fly.

Regarding a comparison of airspeeds, with all of its advanced aerodynamics, particularly its laminar flow airfoil, at most altitudes the Comanche 250 easily matches or betters the speed of a similarly powered Bonanza. While practical experience with both aircra proves this to be true (see below), it runs contrary to Beechcra’s advertised airspeeds for the Bonanza. However, many believe that Beechcra’s published airspeeds are inflated and were possibly recorded when the Bonanza was very lightly loaded and, of course, any aeroplane will fly faster when lightly loaded as the power loading is reduced.

Each aeroplane has its particular aerodynamic advantages and disadvantages. The Bonanza’s advantages are a thinner wing which is small for the aeroplane’s weight, a slightly narrower, round profile fuselage, and a slightly cleaner cowling. The Bonanza’s main undercarriage is fully enclosed with secondary doors when retracted while the Comanche’s main undercarriage is partially exposed to the airstream and the Bonanza’s flap hinges are internal while the Comanche’s are exposed to the airstream. However, the Bonanza’s wing’s airfoils are a traditional NACA 23000 series where maximum thickness is a traditional 25-30% of chord (see below).

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Taken altogether, except for its wing’s airfoil, the Bonanza’s airframe is just a bit cleaner than the Comanche’s. However, the Comanche is generally as clean as the Bonanza, except for the above, but it has one great advantage as said; the Comanche’s wing has a laminar flow airfoil (see diagram above), giving it a distinct airspeed advantage.

Additionally, as altitude increases and the air begin to thin out, the advantage of aerodynamic cleanliness begins to dwindle. A good example of this is a comparison of the high altitude performance of the P-51D “Mustang” and the P-47D “Thunderbolt”. While the compact and far sleeker Mustang is much faster than the larger and draggier Thunderbolt at similar power settings at low to middle altitudes (up to 20,000’), at the similar power settings the Thunderbolt easily catches and passes the Mustang above 32,000’.

Similarly, published performance specs not withstanding, the Comanche begins to gain on and exceed a similarly powered Bonanza at or above 16,000’ leading to the widely held opinion that all Comanches ought to be turbocharged so that they may best take advantage of their excellent already built-in high altitude eiciency.

The Comanche’s higher AR wing is also longer than the Bonanza’s by 3’ 2” which is a substantial dierence in wings of these spans (see specifications charts below). The Bonanza’s shorter wing presents a smaller frontal area and therefore less drag than the Comanche’s longer wing. However, this is oset, as said, by the Comanche’s laminar flow airfoil as compared the Bonanza’s traditional airfoil.

The Comanche’s higher AR does not increase its airspeed but its eiciency permits a greater useful load, faster rate of climb, shorter takeo and climb to 50’ distances and gentles its low-airspeed (high Alpha) and departed flight regime (stall/ spin) as compared to the Bonanza’s far less forgiving low airspeed an departed flight regime (remember that down spring).

So it appears that the Comanche’s and the Bonanza’s aerodynamic advantages and disadvantages cancel each other out for the most part with the Comanche having a slight edge over the Bonanza despite Beechcra’s apparently exaggerated airspeed claims.

One feature Piper was not at all

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Here is one of the very first adver tisements made shortly after the launch of the Comanche:

Piper speaks of a “most advanced business plane”; one tha t is both rugged and beautiful. It’s roomy, fast, economical, and safe.

Far left: No camping out or western adventures with the family implied here. “ This a serious business aeroplane for serious businessmen”, this ad clearly says.

Left: The Comanche quickly bec ame the #1 selling high performance single engine aircraft in the world. By 1961, the Comanche captured 39.4% of the single engine retractable market, while Beechcraf t had 30% and Cessna

11.5%. These “big three”, plus Mooney, would slug it out over the next decade.

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Business and r ange are the key selling points here.

reluctant to point out, is the design of the Comanche wing itself. From a Piper Comanche advert:

“Massive quality construction: Look at the Comanche’s deep, 12-inch spar, check construction throughout and you’ll see why the Comanche has such a magnificent structural safety record.”

If we take a closer look at the wing internally, the Comanche’s main spar is at the 50% chord position, travelling into and through the main cabin and passing under the rear seat which provides the rear passengers with a comfortable, flat floor. Additionally, the Comanche’s wings have two sub - spars, fore and a which are joined together at the factory as one piece which is then mounted to the fuselage. The result is an incredibly strong wing.

By comparison, the Bonanza’s wing has its main spar at approximately the 25% chord point and there is no other equally robust sub spar. Also, the Bonanza’s wings are bolted to the fuselage independently as separate units.

On this page and the previous page is a selection of Piper advertisements which give some insight as to how Piper marketed the Comanche.

AND THE WINNER IS…

It is a ubiquitous trait of the human personality to wish to bring down that and those who stand at the top of the mountain. As children we play the game “King of the Mountain” in which this what we try to do and it all seems to us to be a most natural endeavour. Generally, people are especially unhesitant and glad to tear down that thing or person which or who has proclaimed itself to be “best.” This is understood and herein acknowledged. With this in mind I have tried to be most careful and judicious before casting aspersions. Still, it is not at all unfair to subject the “King”, particularly one which is selfproclaimed, to be the subject of careful scrutiny and assessment to see if such an exclusive and superlative accolade is wellearned and deserved. This may be a particularly American (and Commonwealth, etc.) attitude given our fundamental antiaristocratic genesis and culture, but it is not, I think, an exercise that lacks merit by anyone or at any time. Aer all, how else may we accurately judge the value and validity of such claims?

In 1957 William Piper sought to harness

and apply the most modern aeronautic

Finally, some fun with the family at an exotic vacation spot. Piper usually combined other Piper aircraft in one adver tisement. Here we also see an Az tec t win and early Cherokee.

The entire Piper line is shown but the Comanche is most prominently placed in this ad.

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While more modest in its advertising campaign than Beechcr aft, Piper was not shy about clearly pointing out what made the Comanche so good.

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science available in his passionate quest to build the “best” GA aeroplane he could and to throw down the King of the Mountain, the Beechcra Bonanza and to replace it with the Comanche. The name “Comanche” itself may have been deliberately and complimentary chosen by Piper given that the actual Comanche Nation was a noble, powerful, fierce, feared and dominant tribe in the southwest part of what became the United States.

I think that it is safe to assume that before Piper began the Comanche’s design phase that the engineers at Piper Aircra analysed the Bonanza from nose to tail and wing tip to wingtip. They surely flew it for countless hours and took careful notes of its best and worst characteristics. The result was the Piper 1958 Comanche 250, purpose-built to beat the Bonanza at its own game. Well, did Piper succeed?

ONE PILOT’S STORY

The “Sky Roamers” has been a popular flying club since the 1950s. It owns 22 aeroplanes, has 250 members and is based at “Bob Hope Airport” in Burbank, California. In 1958, Robert Wall, a retired

U. S. A. F. pilot became the chief pilot for the club. Just aer he took his position at the club the Sky Roamers began to think about purchasing its first aeroplanes with a retractable undercarriage. Aer much discussion the choice came down to two, the 1957 H35 Bonanza and the 1958 Comanche 250.

Mr. Wall recalls, “We were looking to buy four retractables, so the stakes were pretty high. We decided to test the two representative models available at that time. On paper, the airplanes were pretty evenly matched, 240 hp in the Bonanza, 250 hp in the Comanche,” he says.

The club discussed a fair test for the aeroplanes. “We decided to fly an out-andback from Burbank to Phoenix with four people in each airplane and fuel to gross weight. Mr. Wall reports, “The Comanche was the winner in almost every category hands down. Everyone loved the way the Bonanza handled, but the Comanche out-climbed the Bonanza at all altitudes and out-ran it at all power settings. I was impressed. Eventually, the club wound up buying four Cessna 210s instead of the Comanches, and that turned out to be a big mistake.”

Speaking about his personal choice for an aeroplane Mr. Wall says, “I finally found my ideal airplane, a nice 1958 Comanche 250, up in Minnesota in 1983 and decided that was the one I wanted. It’s far more stable than the others, it’s about the same speed or perhaps a little quicker than the Bonanza, but it will carry far more than the V-tail of the same vintage and horsepower. And it certainly didn’t hurt that it was less expensive than the Bonanza or most anything of comparable horsepower on the market.”

So, did the Comanche actually kill the Bonanza or ever take its place at the top of the GA food chain? Well, maybe in some eyes it should have, but the answer

is clearly, no. The Beechcra Bonanza has remained at the top of GA aeroplanes and has become a veritable institution. However, the Comanche did compete well with it and better in that regard than anything else in its time. Piper and Beechcra continued to strive with each other until the Comanche suddenly ceased production in 1972, along with the excellent, sleek and speedy Twin-Comanche. The “oicial” reason for this is the result of catastrophic damage to Piper’s Lock Haven, PA factory caused by the record rising of the nearby Susquehanna River due to Hurricane Agnes. As to the real reason for Piper ceasing the production of these fine aeroplanes, speculation and rumours abound.

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Mr Wall is not the only one, nor is he merely one of a small group of pilots who have discovered that the Emperor Bonanza has no clothes or is at least in need of a serious make - over. Herein I have been more than slightly critical of the Bonanza on a number of levels and in each of such instance have done my best to show why what I have written is not merely opinion, biased or otherwise. Still, we at A2A have been and are reluctant to cast aspersions, even those which have been well-earned, upon any aircra manufacturer or aeroplane. We love aeroplanes and those who make and fly them.

That said, I don’t think that I’m telling any tales out of school when I report that Scott and I have been batting around such criticisms which I have been made regarding Beechcra’s published performance claims for the Bonanza and particularly in reference to a Comanche of equal power. We asked: Are we being too tough? Are we biased? Are we being fair? And, the ultimate, unavoidable question: Are we telling the whole and unvarnished truth?

Well, aer much discussion we came to the realisation that the only way to discover the truth, notwithstanding decades of other pilot’s testimony, was to do a real- world flight test of a Bonanza flown at equal power to the Comanche and see what the numbers show us.

On the aernoon of June 6, 2015 Scott went flying in a E-33A Bonanza. This aeroplane has a standard cruciform tail and a 285 h.p. engine. Given that there exists no evidence on record that a V-tail adds or subtracts from the airspeed of a Bonanza, we did not see the standard cruciform tail as a problem. The higher powered engine in the Bonanza was easy to work with and power settings were set during the flight which equalled the power of the Comanche’s 250 h.p. engine.

The results are (drum roll): The Bonanza was loaded 500 lbs. under maximum gross weight with three on board, two in the two front seats and Captain

Jake (Scott’s son) in a rear seat. It is a more cramped side to side inside than the Comanche but has impressive headroom. The outside air ventilation was discovered to be far less eective than the Comanche’s. The Bonanza, even loaded as lightly as it was and with more power available does not climb as well as the Comanche at maximum gross weight by many hundreds of feet per minute. I attribute this, in part, to the Comanche’s more modern laminar flow airfoil and even more to the higher aspect ratio of the Comanche’s wing.

Airspeed tests were made at 6,000’ with the power adjusted, as said, to match the power of the Comanche at that altitude. Even taking the lower weight of the Bonanza on this flight into consideration, it never was able to equal by many knots the airspeed of the Comanche or even its own published “oicial” performance specifications.

When approaching a 1-G stall in the Comanche a warning light starts blinking along with airframe bueting with increasing intensity as the stall approaches. It literally slaps the pilot on the back and clearly indicates (shouts) as if to say, “Alright, get ready, were going to stall very soon unless you unload the wing by pushing forward on the yoke.” If during this the yoke is held all the way back the Comanche will finally stall with a moderate break and a wing will drop, which is instantly recoverable by releasing back pressure on the yoke.

Doing the exact same maneouver in the Bonanza, there is an audible warning that sounds well ahead of the stall, but the aeroplane continues to fly smoothly right up to point just before the stall, then there is a brief airframe rumble then an immediate, precipitous stall with a sharp wing drop. In the Bonanza there is no long period of bueting as you approach the stall. Interestingly, and quite satisfyingly for an old aerodynamicist like me, this actual, real-world departed flight behaviour exactly matches the polar of the Bonanza’s

23000 series airfoils wherein the Cl steadily rises right up to the point of stall Alpha and then drops o sharply at the stall break. Recovery, however, is not a problem and is much like that of the Comanche. Both the Bonanza and Comanche rapidly accelerate back to cruise speed. Intentional spins are not permitted in either the Bonanza or the Comanche so there were no tests in that area; however, the Bonanza felt more likely to spin out of an ordinary 1-G stall.

To the Bonanza’s credit, its trailing link undercarriage feels far more substantial and smooth upon landing than does the Comanche’s straight oleo strut. Bonanza’s abrupt and sharp stall characteristics generally lead pilots to carry around approximately 1,200 r.p.m. when landing until touchdown.

Between these two aeroplanes, as to performance in every category as well as all of the other features mentioned, A2A’s real-world flight test shows that the Comanche, except for its undercarriage design, is the clear winner on every count.

Today, as newer and even sleeker modern composite designs vie with each other and with the latest version of the venerable, old Bonanza for top dog in the GA high-performance, single-engine market, the Bonanza lives on, albeit since 1982 when the last V-Tail Bonanza was built, in the shape of the venerable, reliable old Debonair and is still in production with no end in sight.

While its time in the market as a new aeroplane was relatively short 14 years (1958-72), since its introduction the Piper Comanche has been and still is one the most highly-respected and desirable GA aeroplanes of all time and a good one in good condition is considered a prime find on the used aircra market. Today there are many thousands of loyal Comanche adherents who firmly believe as I do, and if I say so, with good reason that it is the most beautiful, elegant and overall best performing single-engine

GA aeroplane ever built. Right, Scott?

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Lastly, let ’s take a look at how Piper marketed their corporate image. Always highly photogenic, it’s no surprise that the Comanche was chosen to represent the entire Piper fleet.

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+ 72 hidden pages

A2A Piper Comanche 250 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

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