Top Flite Sierra Instruction Book

and workmanship at the date of purchase. This warranty does not cover any component parts damaged by use
or modification. In no case shall Top Flite Models' liability exceed the original cost of the purchased kit. Further,
Top Flite reserves the right to change or modify this warranty without notice.

In that Top Flite has no control over the final assembly or material used for final assembly, no liability
shall be assumed nor accepted for any damage resulting from the use by the user of the final user-assembled
product.

By the act of using the user-assembled product, the user accepts all resulting liability.

If the buyer is not prepared to accept the liability associated with the use of this product, he is advised
to immediately return this kit in new and unused condition to the place of purchase.

TOP FLITE MODELS, P.O. BOX 721, URBANA, IL 61801

TECHNICAL ASSISTANCE - CALL [phone]

READ THROUGH THIS INSTRUCTION BOOK FIRST. IT CONTAINS IMPORTANT INSTRUCTIONS AND WARNINGS CONCERNING THE ASSEMBLY AND USE OF THIS MODEL.

INSTRUCTION BOOK

Top Flite Models guarantees this kit to be free of defects in both materials

WARRANTY....

2

TABLE OF CONTENTS

INTRODUCTION

............................................3

Precautions....................................................3

DIE PATTERNS

.............................................4

DECISIONS YOU MUST MAKE EARLY

IN THE BUILDING SEQUENCE....................5

Engine and Mount Selection

..........................5

Other Items Required

.....................................5

Supplies and Tools Needed ...........................5

Common Abbreviations ..................................6

Types of Wood ...............................................6

Get Ready to

Build

.........................................6

Wing Tips....................................................... 19

Right Wing Panel Assembly........................... 19

Join the Wing .................................................19

Bolt on Wing ...................................................21

Rubber Band on Wing ....................................22

Install the Ailerons ..........................................22

Center Section Sheeting ................................23

FINAL ASSEMBLY........................................ 24

Bolt-on Wings.................................................25

Rubber Band-on Wings..................................26

Mount the Tail Surfaces .................................26

Tailwheel Assembly (optional) .......................27

Mount the Engine

...........................................28

Install

the Fuel Tank

.......................................36

BALANCE YOUR MODEL

............................37

FINAL CHECKS

............................................37

PRE-FLIGHT

Charge the Radio Batteries............................38

Find

a Safe

Place

to Fly

.................................38

Ground Check the Model ...............................38

Range Check your Radio

...............................38

USING GLUE

.................................................6

ENGINE SAFETY PRECAUTIONS............... 38

NOTES ON SANDING...................................7

BUILD THE TAIL SURFACES

......................7

Hinge Slots.....................................................8

BUILD THE FUSELAGE

...............................9

BUILD THE WING

.........................................16

Guide Tool......................................................16

Left Wing Panel Assembly

.............................16

No Aileron Version

.........................................18

Aileron Version............................................... 19

FINISHING.....................................................30

Balance the Airplane Laterally .......................30

Final Sanding .................................................30

Covering.........................................................30

Covering Tips Using Monokote®......................30

Recommended Covering Sequence ..............31

Fuel Proofing..................................................31

Hinging...........................................................31

Final Control Hookup .....................................32

Aileron Control Hookup ..................................33

How to Make Z-bends ....................................33

Control Surface Throws .................................34

Apply Decals and Trim ............................35,36

Install Receiver, Battery, Switch..................... 36

AMA SAFETY CODE

....................................39

General ..........................................................39

Radio Control.................................................39

FIRST

FLIGHTS

............................................39

Take Off.........................................................40

Flying..............................................................40

Landing

..........................................................41

Landing Pattern Drawings..............................41

PARTS LIST

..................................................43

2-VIEW DRAWING

........................................44

WARNING! THIS IS NOT A TOY!

The model you will build from this kit is not a toy! It is capable of serious bodily harm
and property damage. IT IS YOUR RESPONSIBILITY AND YOURS ALONE - to build
this kit correctly, properly install all R/C components to test fly the model, and fly it
ONLY with experienced, competent help using common sense and in accordance with
all safety standards as set down in the Academy of Model Aeronautics Safety Code.

It is suggested that you join the AMA to become properly insured before you attempt

to fly the model. IF YOU ARE JUST STARTING R/C MODELING, CONSULT YOUR

LOCAL HOBBY SHOP OR WRITE TO THE ACADEMY OF MODEL AERONAUTICS

TO FIND AN EXPERIENCED FLYING INSTRUCTOR IN YOUR AREA.

Academy of Model Aeronautics

1810 Samuel Morse Drive

Reston, VA 22090 [phone]

INTRODUCTION

Thank you for purchasing the Top Flite

GOLD EDITION Sierra.

The Top Flite Sierra is an excellent trainer model
designed to get you off to a great start in learning to
build and fly. After you learn to fly, the Sierra also has
enough maneuverability to perform most basic aero­batics and provide many hours flying enjoyment.

The easy construction, great lines, and included
decals make it easy for you to build a great-looking
model.

The Top Flite Sierra is designed to fly as good as
it looks. Its thick, flat-bottom wing offers strong lift at
slow speeds and great strength. The computer­designed, interlocking structure allows you to build a
straight and true model with smooth confidence­boosting flight qualities.

Please inspect all parts carefully before
starting to build! If any parts are missing, broken
or defective, or if you have any questions about
building or flying this model, please call us at
[phone] and we'll be glad to help. If you
are calling for replacement parts, please look up
the part numbers and the kit identification num­ber (stamped on the end of the carton) and have
them ready when calling.

PRECAUTIONS

1. You must build the plane according to the plans

and instructions. Do not alter or modify the model,

as doing so may result in an unsafe or unflyable
model. In a few cases the plans and instructions may
differ slightly from the photos. In those instances you
should assume the plans and written instructions are
correct.

3

2. You must take your time to build straight true
and strong.

3. You must use a proper R/C radio that is in first
class condition, the correct engine size and correct
components (fuel tank. wheels, etc.) throughout
your building process.

4. You must properly install all R/C and other com­ponents so that the model operates properly on the
ground and in the air.

5. You must test the operation of the model before

the first and each successive flight to insure that all

equipment is operating, and to make certain that the
model has remained structurally sound. Be sure to
check external nylon clevises often. Replace them
if they show signs of wear.

6. You must fly the model only with the competent
help of a well experienced R/C pilot, if you are not
already an experienced R/C pilot at this time.

NOTE: We, as the kit manufacturer, can provide
you with a top quality kit and great instructions,
but ultimately the quality and flyability of your
finished model depends on how you build it;
therefore, we cannot in any way guarantee the
performance of your completed model, and no
representations are expressed or implied as to
the performance or safety of your completed
model.

Remember: Take your time and follow the di­rections to complete a well-built model that is

straight and true.

4

DIE PATTERNS

5

EARLY IN THE

BUILDING SEQUENCE

ENGINE AND MOUNT SELECTION

The recommended engine size range is as fol­lows:

.28-.40-.46 cu. in.

2-cycle

.40-.48-.60 cu. in. 4-cycle
NOTE: The displacement in bold type is the
most highly recommended. However, all

of

these engines will fly the Sierra well.

The supplied MM40 motor mount should
hold most of the two strokes in the range and
some of the four strokes. It is permissible to file
the inside of the mount slightly to fit larger engines
(see photo on page 28). Some engines may
require you to buy a different mount from your
hobby dealer. Study the plans and the engine
mounting section of this bookformore information
and sample installations.

BOLT-ON OR
RUBBER BAND-ON WINGS

The Sierra has been designed and tested
with rubber band-on or bolt-on wings. The rub­ber band on wings will better absorb the shocks
of a crash or landing accident such as a cartwheel.
If you have a good instructor and flying site or
already have some flying experience, you may
want to use the bolt-on wing option.

3 OR 4 CHANNELS

The Sierra flies very well with or without
ailerons. The 3-channel version will be cheaper
and easierto build. The 4-channel version offers
the extra flexibility of aileron control. Ailerons

make cross wind take offs and landings easier

to control, so many instructors recommend

ailerons.

TRICYCLE OR TAILDRAGGER
GEAR

The tricycle landing gear is considered
standard. We recommend the tricycle gear if
this is your first airplane because it offers the
best ground handling as well as straight ahead
take offs and landings. The tricycle gear also
does a better job of protecting the propeller
during bouncy take offs and landings. If you
are sport flying the Sierra or want to learn to fly
a taildragger, provisions have been made to
allow you to build the Sierra as a taildragger.
The Great Planes #L-7 tail wheel assembly
may be purchased from your dealer and
modified slightly to match the drawing on the
fuselage plans.

SELECTION OF WHEELS

The standard recommended wheels

are
two 2-3/4" main wheels and one 2-1/2" nose
wheel. If you are flying off grass or an uneven
surface, you may wish to use larger wheels
than those recommended. The standard
wheels have been tested off of grass and work
fine, but 3" wheels all the way around would

work even better.

If you will be flying a taildragger off of
grass, we recommend using 3" to 3-1/4" main
wheels and a 1" to 1-1/4" tailwheel.

OTHER ITEMS REQUIRED

Three or Four-channel radio with 3 or 4 servos
Engine
Propellers (Top Flite Power Point recommended-see

engine instructions for sizes)

2-1/4" Prop Spinner

Fuel Tank (Most 6 to 10 oz. tanks will tit)
2-3/4" Main Wheels (2)
2-1/2" Nose Wheel (1) (or 1" Tailwheel)
5/32" Wheel Collars - (4-6)

Top Flite MonoKote"

*Model shown covered with 2 rolls of Yellow, plus Missile

Red, and Orange for trim

Silicone Fuel Tubing
Latex Foam Rubber Padding (1/4" thick)
#64 Rubber Bands (10-12 for rubber band-on wings)
1/8" Foam Wing Seating Tape (optional)

SUGGESTED SUPPLIES
AND TOOLS

2 oz. Thin CA Adhesive (Hobbico Bullet Glue is Recommended)

2 oz. Medium CA Adhesive (Hobbico Bullet Glue is Recom­mended)

15-Minute Epoxy (Hobbico Bullet Glue is Recommended)
Hand or Electric Drill
Drill Bits: 1/16", 3/32", 1/8", 5/32", 3/16", 1/4"
Top Flite Heat Sealing Tool
Top Flite Heat Gun

Hobby Saw (X-acto Razor Saw)

X-acto Knife, #11 Blades
Pliers
Screw Drivers
T-Pins
Straightedge
Short ruler
Masking Tape (Suggested for construction)
Sandpaper (coarse, medium, fine grit)*
T-Bar Sanding Block (or similar)
Waxed Paper
Lightweight Balsa Filler

1/4-20 Tap. Tap Wrench (optional bolt on wings)

IsopropyI Rubbing Alcohol (70%)

Dremel Moto Tool or similar (optional)

NOTE: On our workbench, we have four 11" T-Bar sanders,
equipped with #80, #100, #150, and #220-grit sandpaper. This
setup is all that is required for almost any sanding task.
Sanding blocks can be made from balsa for sanding hard to
reach spots. We also keep some #320-grit wet-or-dry

sandpaper handy for finish sanding before covering

6

COMMON ABBREVIATIONS USED
IN THIS BOOK AND ON THE PLANS:

Deg. = Degrees Lt = Left
Elev = Elevator Ply = Plywood
Fuse = Fuselage Fit = Right
LE = Leading Edge (front) Stab = Stabilizer
LG

= Landing Gear TE = Trailing

Edge (rear)

= Box to check after step " = Inches

is completed.

Balsa Basswood Plywood

GET READY TO BUILD

1. Unroll the plan sheets. Re-roll the plans inside
out to make them lie flat. The wing plan sheet has a
cut-line across it. If you have a small building space
you may cut the wing plan into two pieces along this
line.

The fuselage plan sheet does not have a cut-line
across it. It is used mostly for reference and not
much building is done over it. There is not much
benefit in cutting it apart, but you may do so if you
wish.

2. Remove all parts from the box. As you do,
figure out the name of each part by comparing it with
the plans, die-cut patterns, and the parts list at the
back of this book. Using a felt tip pen, write the part
name or size on each piece to avoid confusion later.
Use the die-cut patterns shown on page 4 to identify
the die-cut parts and mark them before punching out.

Save all scraps. If any of the die-cut parts are difficult
to punch out, do not force them! Instead, first cut
around the parts with an X-acto knife. After punching
out the die-cut parts, use your T-Bar or sanding block
to lightly sand the edges to remove any die-cutting
irregularities.

USING GLUE

There are two types of glue that are recom-

mended for building this model: CA and Epoxy.

CA (cyanoacrylate) glue is used for gen­eral construction. It is available in a variety of
viscosities. We recommend you have the fol­lowing two types.

Thin CA has a viscosity similar to water
and is used to glue together parts that fit
together very well and do not require reposi­tioning after glue is applied. Thin CA is espe­cially effective for gluing balsa to balsa. It can
be used to glue hardwoods such as plywood,
spruce, or bass but it is usually necessary to
fillet the joint afterwards with some medium CA.
Thin CA has the ability to "wick" into joints. This
means it will be drawn into very fine gaps
between parts. This characteristic makes thin
CA very useful for a lot of tasks, such as gluing
seams that are already clamped together or
installing CA hinges. Thin CA usually sets very
rapidly, so do not expect to move parts at all
after glue is applied. This rapid reaction may
also produce fumes and a significant amount of
heat. Always use CA glues in a well-ventilated
area.

The other type of CA glue we recommend
is medium (or gap filling). Medium CA is used
in

general construction for parts which have

gaps, require slight repositioning, or involve
hardwoods. Medium CA can be used to make
small fillets between parts in high stress areas.
Medium CA is a very good general purpose
glue and many people use it for the majority of
their building.

Some medium CA glues can be slow to set,

especially when used to fill gaps. A product

known as CA accelerator is available to speed
things up. It is sprayed onto the joint after the
glue is applied and chemically reacts with the
glue causing it to set very rapidly. There are a
few precautions to consider when using an
accelerator...

Use it in a well ventilated area. The rapid
reaction can release irritating fumes at a higher
rate than normal. Do not use CA accelerator on

thin CA!

Be careful when using the accelerator
around plastics. Certain accelerators may
attack some plastics and the vapors may fog

clear canopies. It is best to test the glue and

accelerator on a scrap piece of plastic if one is
available.

Using too much accelerator may cause the
CA glue to react very rapidly and literally boil.
This will result in a joint with a chalky white color
which is not nearly as strong as a normal joint.

Epoxy is used on high-stress joints that
require toughness and vibration resistance.
Epoxy also works well in areas that may en­counter fuel. Its slower cure time allows parts
to be clamped, checked, and realigned if nec­essary before the epoxy sets. Epoxy is avail­able in many different formulas having different
cure times. The single best type of epoxy to
have available when building your Sierra is one
that sets in 15 minutes, but you may also find 5­minute epoxy handy to have around.

them into groups, such as fuse (fuselage), wing, fin
and stab (stabilizer), and hardware.

3. As you identify and mark the parts, separate

7

NOTES ON SANDING

1. Use a block orT-barwhereever possible when

sanding. The flat block will "ignore" glue and
changing wood density and give you a true and
even shape.

2. Always use fresh, sharp sandpaper. Sharp

sandpaper will cut through glue and hard mate-

rials easily, giving an even surface. Older, dull

sandpaper will require more pressure and may

gouge the surface.

1/4" shaped balsa fin fwd
1/4" shaped balsa fin aft
1/4" shaped balsa rudder
1/4" shaped balsa stab fwd
1/4" shaped balsa stab aft
Tapered balsa elevator
1/8" bent wire elevator joiner

BUILD THE TAIL

SURFACES

To build the tail surfaces, you will need the following:

of a paper towel to make sanding easier. Flip the
parts over and apply some thin CA to the other side
of the joint.

3. The notch in the shaped 1/4" balsa stab aft
piece is positioned at the back edge of the stab so the
fin post can protrude through the notch later when
you are told to attach the tail surfaces to the fuselage.
Glue the shaped 1/4" balsa stab (stabilizer) fwd to
the stab aft in the same manner as the fin parts.

150 grit sandpaper to smooth out any unevenness.
Carefully block sand the edges and ends to correct
any slight bumps or mismatches. Align the notch at
the back edge of the stab and the stab TE with the
plans. Mark the fin location on the front edge of the
stab. Draw two lines from these marks to the notch
in the aft edge of the stab.

5. Refer to the cross section on the plans. Use
a sanding block to round the stab leading edge
(except the flattened center portion). Mark the
location of the dorsal fin on the forward edge of the
fin using the plans as a guide and round the fin only
above the dorsal fin. The fin, rudder, and stab should
have their tip edge corners rounded slightly for
easier covering (see the cross sections on the fuse­lage plans).

1. Work on a flat surface covered with waxed

paper. Refer

to the plans to identify the parts and

their

locations.

2. Put the shaped 1/4" balsa fin fwd, fin aft, and
the 1/4" x 3/8" x 8-7/8" balsa fin post together and
check how the parts fit. Block sand the mating
surfaces until they fit well. Hold the parts together
tightly and glue them together with thin CA. Imme­diately wipe off any excess glue with a quick stroke

4. Block sand the surfaces of the fin and stab with

6. Use a smooth ball point pen to draw a

8

centerline along the stab trailing edge, tapered balsa
elevator leading edge, fin trailing edge, and shaped

1/4" balsa rudder leading edge.

7. Referring to the cross sections on the plans,
carefully block sand the elevator and rudder leading
edges to a "V" shape. The centerlines you drew

earlier should remain for hinging later.

NOTE: The rudder may be left at a constant

thickness of 1/4" or you may taper it with a

sanding block to match the top view on the

fuselage plans. For a model that travels at a

relatively slow speed such as this one, it is not
necessary to taper the rudder to make the aircraft
fly properly. If you want to taper it for appearance
reasons, that is fine.

shown on the plans and in the photo. This will make
it easier to align the elevators.

10. Lay the elevators and the elevator joiner over
the plans. Mark where the joiner will insert into the
elevators. Start the hole in the elevators by cutting
a small 1/8" square notch with a sharp #11 knife.
Carefully drill a 1/8" hole into each elevator to the
depth shown on the plans. Use the knife to cut a

groove in the front of the elevator at the root end for

the joiner (as shown in the photo).

11. Make sure the joiner wire will fit all the way into

each elevator and that both elevators lie flat on the
work surface with the joiner installed. Bend the joiner
wire if necessary to make the elevators line up with

each other. Rough up the joiner wire with coarse

sandpaper and clean it with alcohol. Mix some 5-

minute epoxy and use a tooth pick or piece of wire to

push the epoxy into the hole and groove in the

elevator. Push the joiner into the elevators and wipe

away any excess glue. Lay the parts over the plans

to aid in alignment while the glue sets. It is important

that the elevator LE is straight so you will not have

problems when you hinge it later.

12. After the epoxy is cured apply some thin CA
to both sides of the balsa elevator over the joiner to
'harden' the area. Sand the cured glue smooth.

13. Place the fin and stab over the plans and mark
the hinge locations on the trailing edges. Transfer
the locations onto the elevator and rudder leading
edges.

8. Hold the tapered elevator stock over the plans
and mark the locations of the cuts at the center
where the elevator is cut away to allow for rudder
movement. Use a razor saw to cut away the right and
left elevators.

9. Locate the bent 1/8" wire elevator joiner. Use

An alternate method to make a groove in a surface
for a torque rod is to sharpen the end of an appropri­ately sized (1/8") brass tube from the inside with a
#11 knife, then use the tube to cut out the notch for
the torque rod.

14. Cut the hinge slots using

the

technique

a flat file or a grinder to taper the ends slightly as described on the following page.

9

CAUTION!!! You must use extreme care to

avoid cutting yourself when cutting hinge
slots with an X-acto knife. If the balsa breaks
while you are pushing on the knife, the blade
could go into your hand before you know it!
A good precaution is to wear leather gloves
while performing this step.

A. Begin by carefully cutting a very shallow slit
at the hinge location. This first cut is to establish your
cut in the right place, so concentrate on staying on
the centerline and don't cut too deep!

B. Make three or four more cuts in the same line,
going slightly deeper each time. As you make
these additional cuts, work on going straight into the
wood. Continue this process while "wiggling" the
knife handle forward and backward until the blade
has reached the proper depth for the hinge.

C. Trial fit the hinge into the slot. If the hinge is
difficult to push in, re-insert the knife and move it
back and forth in the slot a few times to enlarge the
slot.

BUILD THE FUSELAGE

1. Place the fuselage plan side view on your work

table. Cover it with waxed paper.

2. Use thin CA to glue the separately die-cut

corner of the die-cut 1 /8" balsa upper forward fuse

sides in place as shown in the photo. These parts
are located in the same die-cut sheets (SIE4F07).
Remember that you will be making a right and a left
fuselage side. You may wish to glue from opposite
sides of the wood in order to reduce sanding.

NOTE: The plans may shrink or expand slightly
due to humidity. Do not worry if the parts are not
exactly the same size as the plans.

4. Plug the die-cut 1/8" balsa aft fuse sides into
the forward fuse sides. Sand them lightly if neces­sary to make them fit. Before gluing be sure to align
the parts over the plans. Any "bend" in the fuse sides
will cause the fuselage to twist later. When the fuse

sides are well aligned with the plans, glue the forward
and aft pieces together with thin CA. Add medium
CA to any joints that are not tight fitting.

15. Trial fit the hinges in the slots and trial fit the

rudder and elevator in place on the fin and stab. Do

not glue the hinges until after you have covered
the model.

3. Glue the upper forward fuse sides to the die­cut 1/8" balsa lower forward fuse sides using thin
CA. Mark the inside surface of the fuse sides with the

letters 'R' and 'L to designate the inside of the Right

and Left fuselage sides. Be sure to make a RIGHT

and a LEFT fuselage side.

5. Use a sanding block to sand smooth all of the

joints you have made on the fuse sides.

6. Position the die-cut 1/8" balsa rear fuse

doubler in its place on the inside surface at the rear

10

of the fuselage side. Use the die-cut 1/8" plywood
former F-5 to help you position the doubler (do not
glue the former in until told to do so later). Notice that
the pushrod exit holes do not line up (this is normal
and makes the pushrod installation in later steps
easier). Apply several beads of medium CA to the
doubler and position it on the fuselage side. When
it is aligned properly, press it firmly down to spread
out the beads of glue. Repeat this step for the other
side. Be sure to make a RIGHT and a LEFT.

fuselage doubler over the inside of the fuselage
sides. Notice that it should fit perfectly at the very
front of the fuselage, and then be offset 1/8" in from
the edge of the fuselage sides most of the rest of the
way back. The photos and plans will help you

determine the proper location of the doublers. Use
the front edges and the lock notch in the fuse side
near the lower aft portion of the doubler to align the
doubler.

8. Apply medium CA to the doubler and press it

carefully in position. Apply thin CA around the all
edges of the doubler to reinforce it. Glue the
doublers to the inside of both the left and the right
fuse sides.

AT THIS POINT YOU MUST DECIDE

WHETHER YOU ARE GOING TO BUILD

A TAILDRAGGER OR A TRIKE GEAR

MODEL. THE POSITION OF THE LANDING

GEAR DOUBLER (GD) DEPENDS ON THIS.

area. The die-cut 1/8" plywood gear doublers (GD)

may be placed in two different positions (forward for
taildragger gear, aft for trike gear). Note also the off­center slot in the doubler. The slot should be off-

center toward the aft end of the left fuselage side,

and the forward end of the right fuselage side. Glue
the gear doublers in the position chosen.

10. Glue the right and left die-cut 1/8" balsa
forward fuse bottom pieces together with thin CA.
Add medium CA to any gaps.

11. Glue the right and left die-cut 1/8" balsa
middle fuse bottom pieces together with thin CA.
Place the die-cut 1/8" balsa aft fuse bottom piece
into the notch at the back end of the middle fuse
bottom. Notice that there is a gap in the middle. This
is for former F-4 to key into later. Check that these
parts are properly aligned by positioning them over
the fuselage top view on the plans. Glue with thin
CA. Add medium CA to any gaps.

9. Study the fuselage plans in the landing gear

11

NOTE: At this point you should determine if you
need to use the 9mm x 2" x 2" plywood spacer
plate in your engine installation. Study the
engine installation drawings on the fuse plan
sheet. Short engines such as the OS .40 FP
require the use of this plate. Longer engines
such as the OS .40 SF or 4-cycle engines do not
require the use of this plate.

12. Glue the right and left die-cut 1/8" balsa aft

fuse top pieces together with thin CA. Note the die-

cut "bumps" at the aft end of the aft fuse top. Trim
these off with a straightedge and a sharp knife.

13. Use medium CA to glue the die-cut 1/8"
plywood firewall F-1A (1A) to F-1B (1B). F-1A is
centered on the slightly larger F-1 B. Make sure the
side of F-1A with the punch marks on it remains
visible. (See the photo at step 14).

NOTE: For the following steps, refer to the firewall
cross section drawing on the fuselage plans. At this

point you must know which engine you will use. If you

are using a recommended 2-cycle engine which fits

into the supplied mount, all the punch marks on F-1A
will be drilled to their appropriate size (in the following
steps). If you are using a 4-cycle engine or an engine
that requires a different mount, you will need to
determine the mounting, throttle pushrod exit, steering

pushrod exit, and fuel line exit hole locations for your

installation. (HINT: Use the four standard mount

punch marks on F-1A to help you locate an alternate

mount by drawing an "X" between them to find the
engine centerline). Regardless which engine you are

using, mount it on this centerline.

14. If you are using the supplied mount, drill the

four punch marks in the middle of F-1 with a 5/32"

drill. Use the firewall (F-1) cross-section on the
fuselage plans to positively identify these hole loca­tions. While you have the 5/32" drill bit out, drill 5/32"
holes through the two punch marks in the die-cut

1/8" ply landing gear plate (LGP).

15. Drill 1/4" fuel line exit holes at the top edge
of F-1. The punch mark locations should be OK for
most engine installations.

16. Drill a 3/16" throttle pushrod hole in F-1 in the

location you determined. A punch mark indicates

the "standard" pushrod exit location.

17. If you are using the tricycle landing gear, drill

a 3/16" pushrod exit hole in F-1 at

the

appropriate

punch mark location.

18. Drill 3/16" pushrod holes at the punch marks

in die-cut 1/8" plywood formers F-2 (2), F-3 (3), and
F-4 (4). Refer to the cross-sections on the fuselage
plans to confirm the pushrod locations.

the MM40 motor mount on one side of the plate and

mark the four mounting hole locations. Drill the holes
in the spacer plate with a 1/8" drill bit.

19. If you are using the 9mm spacer plate, center

4-40 x 1" Machine Screw No. 4 Flat Washer

20. Gently tap the 4-40 blind nuts into the back

(F-1 B) side of the firewall. Bolt the motor mount (and
the 9mm spacer if required) to the firewall using the
supplied 4-40 x 1" machine screws and

#4

wash-

ers. Carefully apply a small drop of thin CA to the

12

1/8" plywood former F-5 (5) in place to confirm a
good fit.

perimeter of the flange on each 4-40 blind nut.
Remove the motor mount.

21. Use a small round file to blend the pushrod
exits at the aft end of both the fuselage sides to allow
the outer pushrod tubes to exit at the proper angle

as shown on the fuselage top view and in the photos.
If you do not have a file, use a #11 knife to shape the
pushrod exits as shown in the photo. Hold die-cut

IMPORTANT NOTE: All formers (F-1 through
F-5) are glued in with the stamped numbers
facing forward and upright as shown in the
photos. This is necessary to maintain proper
pushrod routing.

22. Use medium CA to glue the die-cut 1/8"
plywood former F-2B to the left fuselage side. Use a
90 degree triangle to keep the former perpendicular
to the fuse side while gluing.

23. Glue the die-cut 1/8" plywood former F-3 to
the left fuse side in the same manner as F-2. (The
photo for this step is at the top of the next column).

24. Push the 1 /4" ply wing bolt plate into position
just ahead of F-3 but do not glue yet. If the fit of this
plate is too tight, sand it slightly till it fits comfortably.
(Install this plate for strength even if you are using
rubber band-on wings.)

side structure. When all the alignment tabs on F-2

13

and F-3 are thoroughly engaged by the right fuse­lage side, turn the fuselage upright as shown in the
photo and apply medium CA glue to the joints of the
right fuse side and F-2 and F-3.

26. See the photo above step 29 for the proper
position and orientation of the die-cut 1/8" plywood
former F-4. Use medium CA to glue former F-4 in its
place between the fuselage sides. Snap the die-cut

1/8" plywood former F-5 into position at the back of

the fuselage but do not glue yet; instead, use some

masking tape to hold the fuselage together. Re-

member all of the former I.D. numbers face forward.

sembled earlier) into position between the fuselage
sides, sanding if necessary for a good fit. Use some
masking tape to hold the fuse together.

tween the fuselage sides. Use a strip of masking

tape to hold the fuse sides together at the front. Do
not glue the firewall yet.

28. Work the aft fuselage bottom pieces (as-

30. Position the firewall (F-1A/B) in place be-

27. Snap the landing gear plate (LGP) into

29. Check the previously assembled, unglued

31. (If you are making the taildragger version, put
position at the fuse bottom. If you are building a
taildragger, make a duplicate of LGP (but without the
holes) out of scrap 1/8" balsa and substitute it at the
tricycle LGP location. The plywood LGP will be
installed in step 31 for the taildragger. Check to see
that the holes for the landing gear line up with the
slots in the gear doublers (GD). Do not glue yet.

parts for fit and alignment. Correct any problems.
Apply medium CA from the inside of the fuselage to
any unglued joints involving the following parts: F-3,
F-4, F-5,and LGP. Use thin CA to glue the fuse
bottom to the fuse sides from its front edge back to
F-5. The very aft portion will be glued later when the

tail surfaces are installed.

the 1 /8" plywood LGP in place between the fuselage
sides at the taildragger position shown on the fuse-

lage plans.) Work the 1 /8" forward fuse bottom sheet
joined earlier into position between the fuselage
sides. Use masking tape to hold the fuse bottom in

place.

32. Flex the fuselage sides outward and apply
medium CA or epoxy to the edges of the firewall.
Use

masking tape to hold the joint closed while the

14

glue cures. Glue the forward bottom sheeting to the

fuse sides, the firewall, LGP, and former F-2 with thin

CA followed with a fillet of medium CA.

member (FC) to the forward bottom sheeting as
shown on the fuse plan side view. This piece simply
stiffens the fuselage floor in the tank area.

rudder and elevator pushrods. Glue them securely
to the fuselage sides, F-5, F-4, and F-3.

33. Glue the die-cut 1/8" balsa fuselage cross

36. Trial fit the die-cut 1 /8" plywood back window

34. Sand the outside of two of the 24" outer

35. Snap the previously joined aft fuse top into

place on top of the fuselage. Use masking tape to

hold the fuse top in place. Wick thin CA glue into its
joints with the fuse sides and the formers. Do not
glue the area behind F-5 yet. Remove the tape and

run thin CA down the joints again to make sure they

are thoroughly glued.

(BW) in its place on the fuse top. Refer to the
fuselage side view; for best results, bevel the fore
and aft edges of the window to provide a better fit.
HINT: To eliminate difficult sanding later, round the
"lock tabs" on the outside edges of the plywood
windows to a radius similar to that shown on the plan
cross-sections before gluing the windows in.

37. Glue the back window in with thin CA. Then

add some medium CA if required.

38. Wick thin CA into all joints involving the wing
bolt plate. After this has cured, apply a fillet of epoxy
or medium CA around the wing bolt plate.

pushrod tubes so glue will stick to them. Work
these into position as shown on the plans for the

15

39. Round the outside of the "lock tabs" on the
die-cut 1/8" plywood front window (FW) as you did
on the back window. Fit the front window into place.
Glue with thin and medium CA. You may round the
corners of the fuselage to match the cross sections
as you go, or you may wait until the fuselage is done.

40. Sand the edges of the die-cut 1/8" plywood
fuel tank hatch till they are smooth. Test fit the

hatch in place. Trim the hatch or trim back the notch
in the front of the fuse side doublers until the hatch

fits well. Round the right and left edges of the hatch

to a radius like that shown in the firewall (F-1) cross
section.

41. Use CA to glue the die-cut 1 /8" plywood hatch
retainer tab to the inside of the hatch as shown in the
photo and on the fuse side view.

indicate the location of the No. 2 x 3/8" sheet metal
screws used to hold the hatch on. Check to make
sure these will direct the screws into the firewall.
Tape the hatch in place on the fuselage. Drill a 1/16"
hole through the punchmarks into the firewall. Re-

move the hatch and enlarge the holes in the hatch
only to 3/32". Screw the hatch down with the sheet

metal screws to confirm a good fit.

cut a gap in the forward fuse bottom sheeting under

No. 2 x

3/8 Sheet Metal Screw

42. The punch marks in the front of the hatch

43. If you are building a taildragger, you need to

the LGP to allowthe main landing gearto be installed

(as shown on the fuselage plans). The pre-cut 1/8"
x 9/32" x 3-3/4" plywood LG aligner strips are the
same ones used for the tricycle gear. Fill the gap in

the 1/8" balsa bottom sheeting at the tricycle gear

location with scrap 1/8" balsa.

44. Test fit the wire main landing gear into the
holes in the fuse bottom. In orderforthe landing gear
to lie flat on the bottom of the fuse, it is necessary to
remove a little material from the inside edge of the
5/32" holes to allow for the bends in the wire. Do this
with a round file or a knife.

45. Put the two bent wire main landing gear
pieces in place on the fuselage bottom. Slide the
pre-cut 1/8" x 9/32" x 3-3/4" plywood LG aligner strips

in place fore and aft of the main landing gear. Sand
the edges of the strips if necessary for a good fit.
Glue these strips in place with medium CA, being
careful not to glue in the landing gear wires.

16

Nylon Landing Gear Strap

No. 2 x 3/8 Sheet
Metal Screw

46. Put the main landing gear back in position and

place two molded nylon landing gear straps over
the wire LG as shown in the picture. Mark, then drill
four 1/16" pilot holes. Use four No. 2 x 3/8" sheet

metal screws to hold down the LG straps. The

landing gear may be removed until after covering.

This completes the basic construction of the

fuselage.

BUILD THE WING

NOTE: The SIERRA wing, much like the fuse, is

designed so all the major components can be fit

together without glue. This allows you to check

that the pieces are properly fit and aligned before

applying glue to the joints. The wing plan may

be cut in half along the line provided if you wish.

1. Tape the LEFT WING PANEL portion of the

plan over your work surface. (The best work surface

is a very flat board that you can pin into. "Celotex,"
a type of board you can find at a hardware store or
home center, is an example of one). Cover the left
wing panel section with waxed paper so you won't
glue the wing to the plan.

2. Assemble the wing guide tool from the die-cut
1/8" plywood pieces marked "G". The "0" degree
(from vertical) side of the tool can be used to check

the ribs to see if they are vertical. The "4" degree

side will be used later. Do not glue the tool to-

gether.

3. The shaped and notched balsa leading edges
and trailing edges are joined by a thin layer of balsa.

These are cut apart in one of two ways:

A. Break the pieces apart and clean up the

rough edges with a sanding block.

-OR-

Hold knife at an angle
when cutting apart

LEADING EDGE

B. Carefully run a knife down the edge between

the parts to cut them cleanly apart.

NOTE: The Sierra was designed to use

symmetrical leading and trailing edges (they

have no top or bottom). They do, however, have

a root end and a tip end.

4. The tip ends of the leading and trailing edges
are the ends with a notch very close to the end. Mark
the leading and trailing edges with a "T" to designate
the tip. T-Pins

T-Pins

Spar

Work Surface

5. Use the criss-cross pin technique shown in
the illustration to pin a 3/8" x 3/8" x 30" balsa spar
over its location on the plans. Pin the spar in 3 or 4

places. (The photo for this step is at the top of the
next column)

Xacto knife

17

TWO WARPED SPARS INSTALLED

THIS WAY WILL RESULT IN A

STRAIGHT WING

TWO WARPED SPARS INSTALLED

THIS WAY WILL RESULT IN A

WARPED WING

Photo for Step 5

6. Remove the wing ribs

R-1's,

R-2's, and

R-3's from the die-cut sheets. Slide twelve 3/32"

balsa R-3 ribs into place on the bottom spar.

8. Insert the back of the ribs into the notches

in the trailing edge.

NOTE: The plans may shrink or expand slightly
due to humidity. Do not worry if the parts are not
exactly the same size as the plans.

9. Adjust the positions of the leading and
trailing edges left or right until the ribs line up with the
plans. Pin the leading and trailing edges tothe board
so they won't move.

10. Lay two pieces of scrap 1 /16" balsa (from

the die-cut center section sheeting SIE4W05 or

SIE4W06) near the leading and trailing edges under
the location of rib R-2 (this will shim up the rib to allow
for the sheeting later). Push rib R-2 into place as

shown on the plans. Make sure the ends of the rib

engage the notches in the leading and trailing edges.

11. Insert the 3/8" x 3/8" x 30" top spar into the

notches in the ribs.

12. Make sure all the R-3 ribs and the leading
and trailing edges are resting on the flat work sur­face. Make sure the ribs are inserted all the way into
the notches. The "guide tool" is used to check that
the ribs are vertical.

13. Apply thin CA to all the joints involving the

ribs, spars, leading edges, and trailing edges.

NOTE: When gluing the spars to R-2, make sure

the spars are centered between the dihedral

brace notches in R-2.

7. Insert the front of the ribs into the notches

14. Remove the pins holding the spar in place

in the leading edge. Remember to orient the LE with

the

"T"

at

the tip.

but leave the panel pinned flat on the board by the
leading and trailing edges.

18

15. With the panel held flat on the table, use
medium CA to glue in the pre-cut 1/16" x 1-1/2" x2"
balsa shear webs between the R-3 Ribs. Refer to
the plans. Notice there are shear webs on both
sides of the spars outside the first two R-3 ribs and
only behind the spars between the remainder

of

the R-3's.

NOTE: The function of the shear webs is to keep
the spars from collapsing. They will not and need
not touch or be glued to the ribs. They should be
thoroughly glued to the spars.

16. Make sure the wing panel is still lined up

properly over the plan.

17. Position the 4 deg. side of the guide tool
exactly where the end of the bottom spar is shown on
the plans. Use a pen to mark an angled line on the
top and bottom spars.

18. Use the guide tool to mark angled lines

on
the leading and trailing edges from where their
bottom ends are shown on the plans.

19. Use a razor saw to cut off the spars and the
leading and trailing edges at the marked angles. A
T-bar is used to "clean up" the angled ends of the
spars, leading edges, and trailing edges.

20. Use a razor saw and a T-bar to trim the tip

ends of the spars and leading and trailing edges
flush with the outermost R-3 rib.

If you are building the 3-channel wing (without
functioning ailerons), follow the instructions in
the shaded box. If you are building the 4-channel
wing, skip to step 24.

NOTE: The LEFT WING PANEL plan and its
cross-sectional view show the "no aileron"
version.

19

21. The 17/32" x 1-1/2" x 30" tapered
balsa aileron stock fits against the trailing
edge stock with its lower surface flat on the
table. Glue the aileron stock to the trailing
edge of the wing. (See the photo on the
previous page.)

22. Trim the tip end of the aileron stock

flush with the end of the wing.

to the wing trailing edge at the tip as shown on the

RIGHT WING PANEL drawing. (This is done to the
right and left wing.)

26. Trim and sand the aileron stock flush with

the tip of the wing.

it to final shape. HINT: Put masking tape over the
surrounding structure when sanding items such as
the wing tips to protect areas you don't want sanded.

REPEAT STEPS 5-29 OVER THE

RIGHT WING PANEL PLANS TO

BUILD THE RIGHT WING.

23. Trim and sand the root end of the
aileron to match the 4-degree angle of the TE
and spars.

SKIP TO STEP 27

24. Carefully cut a 1-5/8" long piece off the

MAKE THE WING TIPS

27. Look at the FRONT VIEW of the wing on

the plans to see the proper orientation of the 15/32"

x 1-5/8" x 11-1/4" tapered balsawingtips. Thesmall
end of the taper is positioned at the bottom edge of
the wing.

28. Hold the wing tip up to the end of the wing.
Trace the top of the airfoil onto the wing tip. Saw or
carve the wing tip to the rough shape of the wing,
leaving it slightly oversized.

JOIN THE WING

braces. Put reference marks at the center of the

braces. NOTICE: The dihedral brace with the "lock
bumps" for the aileron servo tray is positioned on the

aft side of the spars (these bumps may be trimmed

off if you are not using ailerons).

17/32" x 1-1/2" x 30" tapered balsa aileron stock .

25. Glue the 1 -5/8" long piece of aileron stock

29. Glue the wing tip to the wing. Block sand

31. Test fit the two wing panels together with the
dihedral braces in place. Check to see that the
spars, leading edges, and trailing edges match up
well. Make adjustments if necessary.

The dihedral angle (the angle at which the wings
are "bent up") is not considered critical. This
angle is established by aligning the spars with

20

the dihedral braces. For your reference, if one
wing panel is resting flat on the table, the other
wing tip should be approximately 4" off the table.

32. Look ahead to the photos with steps 33 and

34 for a view of the joined wing. Spread a layer of 15-

minute epoxy onto the matching surfaces of the
dihedral braces and the LEFT wing panel spars.
Align the dihedral braces with the top and bottom

edges of the spars. Clamp or tape the braces in

position until the glue sets.

NOTE: If there are any small gaps between the

ends of the spars or LE's or TE's, do not be

overly concerned. They will not significantly

weaken the structure. After the wing joining

process is complete, fill them with scrap balsa

and medium CA glue.

33. When the epoxy is set, apply a thin film of
epoxy to the dihedral brace and the right wing
spars, slide the two wing panels together, and
carefully align the spars with the dihedral braces.
After the epoxy is cured, if any of the dihedral brace

joints do not appear to be thoroughly glued, apply an

extra fillet of epoxy to them.

34. The die-cut 1 /8" plywood forward center brace
(F) is glued in next. It should be centered on the
leading edge so the 1/16" balsa top and bottom
center sheeting will lap onto it. Align the left and right
leading edges and glue the brace in place with CA or
epoxy.

35. The die-cut 1 /8" plywood aft center brace (A)
is centered on the trailing edges. Align the left and
right trailing edges and glue the brace in with CA or
epoxy (if you are building the 3-channel version, the
fixed aileron stock should be aligned and glued
together at this time).

NOTE: If you are building the 3-channel version,
do not punch out the cutout for the aileron servo
in R-1C. Instead, glue it permanently in place.
Punch it out as shown in the photo at the top of
the next column for the 4-channel version.

together to form a 1/4" thick part. Glue the two die­cut 1/8" R-1C's (1C) together to form a 1/4" thick
part.

two lines forward from the slot in R-1A as shown in
the photo, for later reference.

centered to allow for the top and bottom center
section sheeting as shown in the cross-section
drawing beside the right wing panel.

36. Glue the two die-cut 1/8" balsa R-1A's (1A)

37. If you are using the bolt-on wing option, draw

38. Use medium CA to glue R-1C in place. It is

39. Put R-1A in place as shown in the cross

21

section. If you are using rubber band on wings, glue
it with CA. If you are using bolt on wings, transfer the
marks from R-1A onto the forward center brace (F)
and remove R-1A.

DO STEPS 40 - 49 FOR

BOLT ON WINGS

40. Draw a vertical center line on the forward

center brace.

41. Drill a 1/8" pilot hole into the forward
center brace (see the photo). The angle of this
hole will obviously not be correct, so you need
not go all the way through the balsa leading
edge. Just go through the plywood.

42. Use the R-1 cross section on the wing
plan to determine where the dowel will exit the
leading edge, and mark this location. Drill a 1/
8" pilot hole from the front of the wing through
this mark, then through the previously drilled
pilot hole in the forward center brace.

43. Gradually increase the size of the drill
until you reach 1/4". Test fit a 1/4" wing dowel
through the hole.

44. Replace R-1 A and glue with medium CA.
Remember that it is centered vertically to allow
for the 1/16" sheeting.

45. Cut away the material in front of the slot
in R-1A to allow the dowel to pass through the
front of the wing into the slot.

46. Insert a 1/4" dowel into the leading edge

and push it all the way into the slot. Put a mark

on the dowel 1/2" ahead of the leading edge of
the wing. Remove the dowel and cut it at the
mark. Round the end of the dowel slightly to
allow easy wing mounting.

47. Glue the dowel in place with thin CA.

22

48. Test the fit of the die-cut 1 /8" plywood R­1 B's (1 B) against the R-1 A's. Trim the Ft-1 B's
if necessary for a good fit. The dowel may also
need to be flattened slightly with a sanding block

to allow the R-1 B's a good fit.

49. Glue in the R-1 B's with 15-minute epoxy.

50. For rubber band on wings, glue the die-cut

1/8" plywood R-1 B's to the R-1 A's, forward center

brace (F), and dihedral brace with epoxy.

DO STEPS 51 - 62 IF

INSTALLING AILERONS

51. Cut out and remove the remaining
piece of balsa from across the servo bay in the
bottom side of R-1 C using a knife or razor saw
(see photo at top of next column).

Photo for Step 51

52. Snap the die-cut 1/8" plywood aileron

servo tray and servo tray support in place as

in the photo. Use medium CA to glue in the
servo tray support while using the servo tray to
hold it in position. Do not glue the servo tray in
at this time.

53. Sand the root ends of the tapered and
grooved balsa trailing edge center pieces so
they will meet properly when they are held
together against the TE. Mark the parts so you
can identify the bottom of the left and right parts.

54. Hold the trailing edge center pieces over
the right wing panel plan. Mark where the
torque rods will exit the bottom of the trailing

edge. The root cross-section gives a view of the
cut-out. Cut a notch in the trailing edge center
pieces to allow the torque rod to exit.

55. Hold the trailing edge center pieces up

to the wing. Transfer the notch locations onto

23

the wing. Use a knife to cut small notches into

the wing TE.

56. Use coarse sandpaper to roughen the
nylon tube on the bent wire aileron torque rod.
Slide the tube toward the threaded end of the
rod. Apply a small amount of petroleum jelly to

the ends of the nylon tube to prevent glue from

wicking into the bearing tube.

57. Assemble the parts as shown in the
photo. Apply a small amount of medium CA to
glue the torque rod bearing tube to the balsa
trailing edge center.

WRONG

RIGHT

58. Use medium CA to glue the trailing edge
center assemblies to the trailing edge of the
wing. Do not get glue in the bearing tube.

60. Following the instructions on page 8,
step 10 for installing the elevator joiner, transfer
the location of the aileron torque rods onto the
ailerons. Drill a 3/32" hole into each aileron to
accept a torque rod. Notch the front edge of
each aileron to accept the rest of the torque rod.

61. Draw a center line on the LE of the
ailerons and the trailing edge of the wing, use
the plans as a reference to mark the location of
the hinges. Make slots for the hinges using the
same technique as you did for the elevator and
rudder.

bar to sand the front edge of the ailerons to a "V"
shape to match the cross section on the plans.

WING CENTER SECTION SHEETING

63.

Lightly write the identity (1-6) of each piece
of die-cut 1/16" balsa wing sheeting using the cut
patterns on page 4 as a reference. Remove the
individual sheets from the blanks.

64. Pieces 1, 2, and 3 form the top wing skins;

4,
5, and 6 form the bottom wing skins. Over waxed
paper, glue the 2's and 3's together to form a left and

a right top aft wing skin (as shown in the photo). Glue
the 5's and 6's together to form a left and right bottom

aft wing skin.

stock pieces to length so they fit between the
wing tip and the center pieces with about a 1/16"
gap at each end.

62. Use a razor plane (if available) and a T-

59. Trim the left and right tapered aileron

24

65. Fit the pieces 5-6 in place behind the spar on
the bottom of the wing. Cut a notch to go around the
aileron servo tray support if present. Glue the wing
skin in place.

66. If you are using ailerons, cut a couple of 1/4"
wide strips from scrap 3/32" balsa, glue them in as
shown in the photo to stiffen the bottom wing skin
where the servo cut-out will be made.

67. For planes with ailerons, snap the aileron
servo tray in position and trace the shape of the cut­out on the bottom wing skin. Remove the servo tray

and cut out a slightly oversized opening for the
aileron servo.

68.

Fit the forward bottom wing skins (4) to the

wing, and glue in place.

69. Fit and glue on the top wing skins (1 and 2-

70. Sand the joints in the center of the

wing with

a block and sharp 220 grit sandpaper.

FINAL ASSEMBLY

1. Fit the wing on the fuselage wing saddle. Trim
the aft edge of the wing trailing edge at the center
with a sanding block if necessary for a good fit.

ELONGATE HOLE

IF NECESSARY

NOTE: For bolt on wings, the wing dowel hole in

F-3 may be oblonged some if required to let the
wing sit flat on the saddle or to allow for wing
seating tape. If the hole requires oblonging, do
so with a round file or a #11 knife.

2. Remove the wing from the fuselage. Mark a

centerline on the 1/16" x 1-7/8" x 5-1/2" plywood

3).

25

trailing edge plate.

Use a knife and a straightedge
to cut about 1/2 way through the plate on the center­line. Bend the plate away from the cut until it starts
to break. Place the plate on top of the wing, and
adjust if necessary. Glue the plate to the wing with
medium CA.

DO THESE STEPS FOR

BOLT ON WINGS

3. Referring to the right wing plan. Mark a

line 5/8" from the trailing edge. Mark two lines

1-3/8" from the wing centerline as shown.

4. Drill two 3/16" pilot holes through the
trailing edge plate and wing TE at the intersec­tion of the lines. Be sure to drill perpendicular
to the surface of the trailing edge plate.

Both distances must

be equal!

A=A

B=B

piece of scrap 1 /4" balsa (or the fin as shown in

the photo) in the slot at the back end of the fuse.

Put a pin vertically into the piece on the fuselage

centerline. Attach a length of string to the pin.

Use the string to check if the wing is on straight

(see diagram).

6. Once the wing is straight, use some
masking tape hold it in place. Drill through the
3/16" pilot holes perpendicular to the trailing
edge plate and through the wing bolt plate in
the fuselage with a #10 (or 13/64") drill.

7. Remove the wing and re-drill the holes in

the wing only to 1/4" or 17/64".

8. Use a 1/4-20 tap and a tap wrench to cut

threads in the plywood wing bolt plate.

5. Place the wing on the fuselage. Pin a

26

9.

Harden the threads in the wing bolt plate
with thin CA glue, then re-tap the threads after
the glue has completely hardened.

1"

1/4-20x2" Nylon Bolt

10. Cut approximately 1" off the threaded

portion of the 1 /4-20 x 2" nylon wing bolts. Bolt

the wing onto the fuselage.

Photo for Step 1

2. Temporarily slide the fin into place. Check the
fit of the parts. The bottom edge of the fin should rest
on the stab.

CORRECT

INCORRECT

two inch portion of the stab/fuse junction only. Re­move the fin. Thoroughly glue the forward two
inches of the stab to the fuselage from the inside
(through the fin slot) and outside (do not go all the
way back to the aft end of the fuse until you are told
to). Be sure to also glue the stab to former F-5.

5. Apply a generous bead of medium CA to the

bottom edge of the fin and to the fin slot in F-5. Slide
the fin into the slot in the fuselage. Check the
alignment to make sure the fin is not leaning. Also
glue the fuse joints at the top corners.

If you are using rubber band on wings, temporarily
slide the dowels into the holes in the fuselage
sides (enlarge the holes in the fuselage with a
round file if the fit is too tight). Align the wing and
attach it with several # 64 rubber bands.

MOUNT THE TAIL SURFACES

1. Slide the horizontal stabilizer (stab) into its slot

in the fuselage. Align the stab by looking down at the

stab reference lines through the fin slot in the upper

aft fuse sheeting. Put a couple of marks on the stab
outside the fuselage sides for reference after the
vertical fin (fin) is installed. (The photo for this step
is at the top of the next column)

3. Sight the alignment of the fin and stab from the
front and back of the model with reference to the
wing. Also sight the fin and stab from the top to check
alignment. Make adjustments to the fuse slots if
necessary so the surfaces are not twisted or skewed.

fuselage joints that are not thoroughly glued. Be
sure to flip the fuselage over and glue all stab, fin
post, and fuselage joints from underneath.

6. Wick thin CA into any remaining fin, stab, and

4. Put a small amount of thin CA on the forward

27

7. Sand the joints at the back of the fuselage
smooth. For a nice touch, sand the outer pushrod
tubes flush as shown in the photo.

8. Round the top edge of the shaped 1/4" balsa

9. Slide the elevator into position using its hinges

to support it (do not glue the hinges yet.) Slide the

rudder into its place. Mark the location where the
elevator joiner contacts the rudder. Cut and sand a
notch in the rudder large enough so the elevator

joiner wire and the rudder do not contact each other

when the surfaces are moved through their range of
motion.

DO STEPS 10-14 IF YOU ARE

BUILDING A TAILDRAGGER

NOTE: Refer to the tailwheel section on the

fuselage plans for details and drawings.

11. If you use a Great Planes L-7 tailwheel
wire, modify it slightly as shown on the fuselage
plan sheet.

Photo of completed tailwheel.

12. Drill into the rudder at the location shown
on the drawing with a 3/32" drill to allow the tail
wire to be inserted into it. Notch the LE of the

rudder to accept the nylon bearing. Harden the
bottom portion of the rudder around the tail wire
with thin CA before covering.

NOTE: Do these steps after the model is
covered with Monokote.

13. Place a small amount of petroleum jelly
at both ends of the nylon bearing to keep glue
out. Use a toothpick to push glue into the 3/32"

hole in the rudder. Insert the tail wire and wipe

away any excess glue.

dorsal fin. Use the seam on the top of the fuselage
to help you center the dorsal fin. Glue it on with thin
CA followed by a small fillet of medium CA.

10. You may make a tail wire from scratch
or purchase a Great Planes L-7 tail wire from
your hobby dealer.

14.

Roughen the forward tab of the nylon
bearing and epoxy it into the fuselage during the
hinging process.

28

MOUNT THE ENGINE

See the ENGINE AND MOUNT SELECTION section

on page 5 for additional information.

THIS PHOTO SHOWS THE INSTALLATION OF AN
OS .40 FP ON THE SUPPLIED MOUNT.

THIS PHOTO SHOWS THE INSTALLATION OF AN

OS .48 SURPASS ON A DAVE BROWN 60 FS
MOUNT. THIS MOUNT MAY BE PURCHASED

FROM YOUR HOBBY DEALER. IT MAY BE
DRILLEDTOINSTALLTRICYCLE LANDING GEAR.

THE FOLLOWING SEQUENCE SHOWS THE IN-

STALLATION OF AN IRVINE 40 ON THE SUP­PLIED MOUNT.

NOTE: The assembly and installation of the fuel
tank and fuel lines is covered on page 36-37. You
may assemble and trial fit your tank while
installing the engine.

1. Study the different drawings on

the fuselage

plans that show engine installations.

Find the one

that matches your installation closest.

2. You should already have determined if you
need to use the 9mm spacer plate during fuselage
construction. Use it as required.

NOTE: If the engine mount supplied in the kit
does not appear to fit your engine (example OS
40 SF), you may have to file the corners of the
engine mount rails to make room for the
crankcase. (See sketch and photo.)

File corners of

rails to fit your

Flat File

MM40

Mount

engine

File Corner

3. To determine the best fore and aft position of

your engine on the engine mount, install the spinner

on the engine. Using the plans as referance, place

the engine on the engine mount so that the spinner

is the same distance from the fuselage. Mark the
location of the mounting bolts and drill the holes with
a 7/64" (or #36) drill. NOTE: If you have access to a
drill press, use it for drilling these holes to insure they
are drilled vertically (See previous photo).

4. Mount the engine with the four #6 x 3/4" sheet
metal screws. (An alternate method is to drill the
holes with a #43 drill, tap them 4-40, then mount the
engine with 4-40 x 3/4" socket head cap bolts, not
included).

5. Remove the muffler and needle valve (if
necessary) from the engine. Bolt the engine and
mount to the fuselage. Determine if any cutouts are
necessary for the needle valve or muffler (see the
photos for ideas). Mark any cutouts that are re­quired.

NOTE: It is best to remove the engine before
cutting out clearance holes, but at least plug the
carburetor intake and the exhaust output port
before making dust.

29

6. Cut out any clearance holes or notches you

marked in the previous step. Mount the muffler.

DO THESE STEPS FOR

TRICYCLE LANDING GEAR

7. If you are building a trike gear and are not
using the 9mm spacer, you will need make an
indentation into the firewall to provide clear­ance for the nylon steering arm. Mark the
location of this cutout under the mount. After
the mount is removed, relieve the area enough
to clear the steering arm (a Dremel Moto-Tool
is handy for this job).

NOTE: The steering arm is rotated away
from the firewall when the axle is aligned for
straight ahead steering. Refer to the photos
and plans for proper orientation.

8. One 5/32" wheel collar is pressed into the
nylon steering arm; then the 6-32 x 3/16"
machine screw is threaded in. This assembly
is used below the mount. The other 5/32" wheel
collar and the 6-32 socket head screw are used

above the mount to retain the nose gear. As­semble the parts as shown to determine the
location of a flat which will be made under the 6­32 x 3/16" machine screw. Disassemble the
parts.

9. Clamp the wire nose gear in a vise and use

the side of a flat file to make a flat spot at the

location you marked.

30

FINISHING

BALANCE THE
AIRPLANE LATERALLY

SPECIAL NOTE: Do not confuse this procedure
with "checking the C.G." or "balancing the air­plane fore and aft." That very important step will
be covered later in the manual.

fore, before covering, you should make a final check
of the entire structure. Fix any dents with a light­weight filler, then sand the entire structure smooth

using progressively finer grades of sandpaper. Sand
major areas to be covered using MonoKote" with
#320 sandpaper just before covering

HINT: Small dents in balsa wood can often be
swelled back out by applying a small drop of water to
them.

Now that you have the basic airframe nearly
completed, this is a good time to balance the airplane
laterally (side-to-side). Here is how to do it:

1. Temporarily attach the

wing and engine (with

muffler) to the fuselage.

2. With the wing level, lift the model by the engine

propeller shaft and the aft end of the fuselage (this

may require two people). Do this several times.

3. If one wing always drops when you lift, it means
that side is heavy. Balance the airplane by gluing
weight to the other wing tip. NOTE: An airplane

that has been laterally balanced will track better

in loops and other maneuvers.

FINAL SANDING

Carefully examine your fuselage comparing the
"corners" with the cross sectional drawings on the
plans. Sand (using a block where possible) the
corners of your fuselage until they match those
shown on the plans.

Nearly every imperfection in your wood struc­ture will show through the covering material; there-

COVERING

Follow the instructions included with your
covering material. Thoroughly read through
them before beginning.

TIPS FOR COVERING WITH MONOKOTE:

Make copies of the 2 view drawing on page 44 of this
manual and use it to plan your trim scheme.

When covering surfaces with corners, cut the mate­rial as shown to allow it to fold up and cover the
corners without gaps or bumps.

Precut strips for covering objects such as elevators.
A permanent marker will put reference marks on

MonoKote, and alcohol will remove them later (for
some tasks, you may be able to put your marks on
the backing where they will not need to be removed).
A metal straightedge and a sharp knife are great
tools to have around for cutting MonoKote.

When covering with Monokote® the top and bottom
of the stab, and the sides of the fin, allow about 1/8"
to 3/16" of covering to lap onto the fuselage as in the
photo.

31

Cover the tips of the ailerons before the bottom and
top.

Cover the wing TE Plate before the rest of the wing.

NOTE: DO NOT, under any circumstances,
attempt to cut the covering material after it has
been applied to the fin and stab, except around
the leading and trailing edges and the tip.
Modelers who do this often cut through the
covering and part-way into the balsa stab. This
can weaken the stab to the point where it may fail
in flight!

Recommended Covering Sequence:

1. Rudder left side

2. Rudder right side

3. Bottom of elevators

4. Top of elevators

5. Stab bottom

6. Stab top

7. Fin left side

8. Fin right side

9. Fuse bottom

10.

Fuse sides

11.

Fuse top

12.

Fuel tank hatch

13.

Ends of ailerons

14.

Bottom of ailerons

15.

Top of ailerons

16.

Wing TE plate

17.

Bottom of left wing

panel

18.

Bottom of right wing

panel

19.

Top of left wing panel
(overlap covering 1/4" at

wing LE)

20.

Top of right wing panel

(overlap covering 1/4" at the LE)

When covering concave surfaces, follow the

iron

with a damp cloth, pressing the covering down.

FUEL PROOFING

1. Fuel proof the firewall area and the engine

compartment. Black K&B epoxy paint was used for

this on one of the prototypes. Thirty minute epoxy,

polyester resin, or polyurethane-based paints will
also work here.

3. Fuel proof any external exposed wood.

MonoKote matching brush on Chevron Perfect Paint

works nicely here.

HINGING

(using

CA

hinges)

NOTE: CA Hinges are hinges made specifically
to be used with CA glue. These hinges have a
plastic core which is laminated with fibers to
allow the CA to adhere to them.

1. Find the slots you made earlier. Open them up
by cutting a small rectangle of MonoKote away with
a sharp X-acto knife.

NOTE: Keep a folded tissue handy to absorb any
thin CA that may drip onto the MonoKote by
accident. Any glue residue can be completely
removed with CA Debonder

2. Fuel proof the inside of the fuselage forward
of F-2. K&B polyester resin and a bent epoxy brush
were used for this on the prototypes. 30 minute
epoxy also works well for fuel proofing.

32

2. Push the hinges half way into the control
surfaces. Wick several drops of thin CA into the slot
from both sides of the hinges.

3. Fit the elevator and rudder onto the airframe.
Make sure that all of them fit and line up properly.
Wick several drops of thin CA into the hinge slots on
the elevator, then the rudder. Be sure to glue the
hinges in from both sides of the surface.

RIGHT WRONG

mark the location of the mounting holes. Drill 3/32"
mounting holes through the marks. Then wick some
thin CA glue into them to 'harden' the balsa. The
horns are screwed in place using 2-56 x 5/8" ma-
chine screws and nylon nut plates.

throttle use horns made out of large, "four armed"

horns. The aileron horn is set up to provide "differ­ential throw." In this case it will cause the ailerons
to deflect "up" more than they deflect "down." The

horn shown is made out of a large, round Futaba

horn that is drilled on the "1" and "4" radial lines
where they intersect the "12.5mm" radius line. (See

the drawing on the wing plan).

4. Make the rudder and elevator pushrods: Cut
ten 5/16" lengths of the inner pushrod tube to act as
spacers. Distribute these on the 34" threaded end
.074" wire pushrods as shown on the fuselage top
view. Note: If the spacers are extremely tight on the

.074 wire, you may cut them down to 3/16". If the
spacers are loose on the .074 wire, use a tiny drop of
CA to glue them to the .074 wire. In any case, they
should not easily move on the wire.

4. Use a toothpick to push 15-minute epoxy into
the torque-rod holes in each aileron. Fit the aileron
in place. Then glue in the hinges using the technique
described above.

FINAL CONTROL HOOKUPS

2 - 56 x 5/8 Machine Screw

Nut Plate

Small Control Horn

1. Install the elevator and rudder small nylon
control horns in line with the pushrod exits as
shown on the plans. Hold the horns in position and

2. Mount the servos into the main servo tray
oriented as shown on the fuselage plan top view.
Mount the aileron servo (if used) in the aileron servo
tray.. Since the main servo tray is adjustable fore and
aft for small CG corrections, do not glue it in until told
to do so.

3. For easy setup and good control response, we
recommend you start off using servo horns resem­bling those shown on the plans. The rudder and

of the pushrods, insert the pushrods into their guide
tubes, and temporarily hook the clevises up to the
control horns. The pushrods will later be marked

and

removed so you can make the z-bends.

5. Screw the nylon clevises well onto the ends

33

AILERON HOOKUP

6. Cut away the bottom wing skin as shown
to provide an aileron lead exit. Use medium CA
to glue the aileron servo tray (with servo) in its
place as shown on the plans.

Nylon Swivel Clevis Nylon Swivel

7. Hook up the nylon swivel clevises to the

nylon swivels. Thread a 12" threaded end

rod
into each swivel clevis. Screw these assem­blies onto the aileron torque rods down to the

height shown on the "Cross Section At

Centerline: (See the photo at step 9.)

8. Mark the locations for the Z-bends in the

aileron pushrods by holding the ailerons neutral

with tape and putting marks on the pushrods

even with the holes in the servo wheel.

NOTE: When attaching the Z-bends to the
servo wheels, you'll need to use a 5/64" drill

to enlarge the holes in the servo wheels.

Make the Z-bends as shown in the following
sequence.

9. Hook up and make final adjustments to

the

aileron linkage.

34

10.

Mount the wire main landing gear. Install your
wheels and tires using wheel collars (not included)
as shown on the plans.

14. Remove the nylon clevises from the aft end
to the pushrods. Remove the pushrods. Make the
Z-bends at the servo end of the wire and reinstall the
pushrods from the front through the fuel tank hatch.

of

the nose wheel steering pushrod (the photos

and

plans show typical throttle pushrod installations).

11.

Mount the engine, muffler, and nose gear.
Temporarily put all the equipment, such as the fuel
tank, receiver, battery, etc., in place so you can do a
preliminary Center of Gravity check to determine the

location of your servos.

12.

Put the main servo tray on its shelf and mount
the wing. Check the center of gravity using the
technique described on page 37 "Balance Your

Model". First decide whether the receiver and bat­tery will go under the fuel tank or under the wing in
front of the servos. Then slide the servo tray fore and

aft to fine tune the balance.

NOTE: Most 2-cycle installations will require the

equipment to be positioned forward.

13. Glue in the main servo tray with medium CA.
Mark the locations for Z-bends on the elevator and
rudder pushrods.

NOTE: See the aileron hookup section for a

description of how to make a Z-bend.

required) from half of the 36" double threaded end
rod and half of the remaining 24" outer pushrod tube

(see the fuselage plans and photos for details). The
nose wheel steering pushrod uses a nylon clevis on
its servo end. Make a 90 deg. bend in the steering
arm end of the pushrod as shown on the fuselage
plans. The nose wheel and throttle pushrods do not
require spacers made from inner pushrod tube.

desire. The prototype switch location can be seen in
the photos. Always install your switch on the oppo­site side of the muffler to keep it away from the oily
exhaust residue.

15. Make the nose wheel steering pushrod (if

16. Make the throttle pushrod from the remainder

We recommend the following CONTROL

SURFACE THROWS:

Some radios have adjustable travel vol­umes (ATV). This feature allows the user to
electronically adjust the travel of the control
surfaces. Most low cost radios used in trainers
do not have this feature so we will describe the
"mechanical" method here.

More Throw

(Continued on next page)

17. Install the switch harness in the location you

35

More Throw

Move the linkages in the direction shown by the
arrows to increase the throw of that surface.
Move the linkages in the opposite direction to
decrease the throws. Always configure the
linkages toward the outside of the horns when
possible. This will tend to reduce the amount of
slop that adds up.

NOTE: Throws are measured at the widest
part of the elevators, rudder, and ailerons.

ELEVATOR: NORMAL ....1/2" UP 1/2" DOWN

(High Rate) 5/8" up

5/8" down

(Low Rate) 3/8" up

3/8" down

RUDDER: NORMAL ... .7/8" RT 7/8" LFT

(High Rate) 1" right

1"left

(Low Rate) 3/4" right

3/4" left

AILERONS: NORMAL ... .9/16" UP 3/8" DOWN

(High Rate) 5/8" up

7/16" down

(Low Rate) 3/8" up

1/4" down

NOTE: "Dual Rates" is a feature on some
radios which allows you to switch the control
surface throws in flight. This allows you to
change the responsiveness of your aircraft de­pending on what maneuvers you are doing. If
your radio does not have "dual rates", then set
up the control surfaces to move at the NORMAL
throws. The SIERRA can be safely flown with
any of the control surface throws listed above.
The higher throws just offer a little quicker
response.

APPLY TRIM

The main pictures show a Sierra covered in Mono-

Kote yellow, red, and orange. Another attractive

option, as shown on the side panel, is covered in

MonoKote jet white, pearl red, and pearl copper.

NOTE: This section gives an overview of how we
often trim our models. Some of the techniques
may seem slightly advanced for beginners, but

they are not really difficult.

NOTE: We use standard MonoKote for almost all
of the trim on our models. "Trim sheets" are not
completely fuel proof, and over time they will
begin to peel up. MonoKote is very thin and
lightweight. When ironed on, it wilt almost never
come off. MonoKote has the added advantage of
being able to go over compound curves since it
is applied with heat.

1. Patterns are provided in dashed lines on the
plan sheets. You may wish to trace these so you do
not destroy the plans. Only one pattern is required
to make the left and right trim pieces using the
technique described here.

NOTE: The better the quality of the cutting board
you use, the better your results will be.

2. The model is first covered completely in its

base color.

3. Choose a piece of trim to start with... for

instance, the forward stripe on the stab. Securely

tape an oversized piece of normal MonoKote,

backing side down, to your cutting board. Tape
another piece of MonoKote, backing side up, on top

of the first piece (this one will be for the opposite side

of the stab).

4. Cut the pattern from the plan sheet, leaving a

healthy border around the lines where possible.

5. Tape the pattern over the MonoKote-covered
cutting board (an alternative is to use a spray glue
such as 3M-77 to hold the pattern to the MonoKote

backing).

6. Always use a very sharp knife and enough
pressure to cut through all of the layers of covering
in

one

stroke.

7. Use a straightedge to cut all of the

straight

lines first.

8. Next, free hand cut all of the

curved

sections.

snags or

mismatches.

10. Use the dashed lines on the plans to locate
the trim on the aircraft. Apply the trim in the same
way as normal MonoKote, but reduce the tempera­ture some to reduce the occurrence of air bubbles.

11. Repeat this process for all of the trim.

9. Separate the trim pieces and clean up any

36

APPLY DECALS

NOTE: The decal sheet does not give you

everything you need to completely trim your

model, but it does provide all the difficult items.

1. Study the plans and the photos on the

box to

determine where to place the decals.

ing

decals.

3. Cut out the individual decal items and apply
them in the appropriate locations. NOTE: Certain
decals are provided which you may use at your
discretion, such as the "TOP FLITE" logo and the
small "SIERRA" decals.

4. The following sequence is recommended

for

applying the

window decals:

2. Thoroughly clean your airplane before apply-

B. Use a couple of small pieces of masking tape
to hold the side windows in their position on the
fuselage.

C. Use a permanent fine tip marker, such as a
"Staedtler Lumocolor 313 Permanent" avail­able at art and drafting stores, to lightly mark
the location of the front window. Mark the
location of the aft edge of the side windows for
future reference.

D. Remove the side windows. Peel the backing
off the front window and stick it to the fuselage,
aligning it with the marks you made at the front
window location.

E. Peel the backing off the side windows.

Carefully align them with the front windows and
the marks you made for the aft edge of the side

windows.

F. When both side windows are in place, peel
the backing off the back window. Align it with
the side windows and stick it in place.

HINT: Use a fine tipped permanent marker to

blend away any slight mismatches or gaps.

HINT: You may carefully apply some thin CA

to the window lap joints with a toothpick to

prevent them from peeling up.

INSTALL THE RECEIVER

AND BATTERY

NOTE: These were put under the fuel tank in the
prototypes as shown on the plans. Additional

foam was put between them and the fuel tank to

hold the fuel tank at the proper height. The
position of the battery and receiver may be
changed to balance the aircraft. There is plenty
of room under the wing ahead of the servos for
the receiver and battery if necessary.

NOTE: If it is necessary to install the receiver
and/or battery in the compartment under the
wing, glue a piece of scrap balsa over the top of
their foam padding to keep them securely in
place.

4. Route the receiver

antenna

in one of the fol-

lowing ways:

A. Route the antenna along the inside of the
fuse side and out of the fuse top, just behind
the wing. Anchor the antenna to the top of the
fin with a rubber band.

B. Install another "pushrod guide tube" along
the inside of the fuse, along the bottom,
exiting just ahead of the rudder. Insert the
antenna through the tube, and leave the
excess length trail behind.

NOTE: DO NOT EVER CUT YOUR RECEIVER
ANTENNA OR ATTEMPTTO FLY A MODEL WITH

THE ANTENNA FOLDED OR COILED UP. THESE

CONDITIONS WILL DRASTICALLY REDUCE THE
RANGE OF YOUR RADIO.

A. Carefully cut out the windows with a sharp

knife allowing about a 1/16" border. Use a
sharp X-acto knife and a straight edge to trim

the decal edges that will lap together at the

fuselage corners exactly at their edges.

NOTE: Do not cut the side windows apart.
Applying them as a single piece will allow
you to keep them lined up with each other.

1. Wrap your receiver and battery in plastic

bags, followed with foam rubber.

2. Install the

battery and receiver

in the

fuselage.

INSTALL THE FUEL TANK

1. Assemble the fuel tank as per the manufacturer's
instructions. Be sure the "clunk" cannot contact the
back wall of the tank and interrupt the fuel flow.

37

2. The tank should be mounted as high in the fuel

1. Accurately mark the balance point on the
tank compartment as is practical. Use foam rubber
to surround the tank on all sides and hold it in
position.

NOTE: There is a fitting on the muffler of most
model engines (especially 2-cycles) known as a
"muffler pressure tap". When the vent line from
yourfuel tank is attached to this fitting, it supplies
the fuel tank with a mild amount of air pressure.
This pressure provides a more consistent flow of
fuel to the carburetor. The result of using this
"muffler pressure tap" is usually an engine that
will run properly whether the plane is climbing,
diving, upside-down, or right-side-up.

3. Route the fuel line from the clunk to the
carburetor fuel intake. Route the fuel line from the
tank vent to the muffler pressure tap, or leave it open

if no pressure tap is available.

NOTE: The fuel system should be completely
free of kinks or leaks. Any of these will cause the
engine to run erratically or not at all.

BALANCE YOUR MODEL

NOTE: This section is VERY important and must
not be omitted! A model that is not properly bal-

anced will be unstable and possibly unflyable.

bottom of the wing on both sides of the fuselage.
The balance point is shown on the plan (CG), and is
located approximately 3-3/4 inches back from the
wing leading edge (1/8" inch back from the center of
the spar). This is the balance point at which your

model should balance foryourfirst flights. Later, you

may wish to experiment by shifting the balance up to
5/16" forward or back to change the flying charac­teristics. Moving the balance forward may improve
the smoothness and provide arrow-like tracking, but

it may then require more speed for take off and make

it more difficult to slow down for landing. Moving the

balance aft makes the model more agile with a

lighter and snappier "feel." In any case, do not

balance your model outside the recommended

range.

2. With the wing attached to the fuselage, all parts
of the model installed (ready to fly), and an empty
fuel tank, position the model with the stabilizer level.

3. Lift the model at the CG marks. If the tail
drops when you lift, the model is "tail heavy" and you
must add weight* to the nose for balance. If the nose
drops, it is "nose heavy" and you must add weight*
to the tail for balance. NOTE: Nose weight may be
easily installed by sticking strips of lead into the
engine compartment beside the engine. Tail weight
may be added by using "stick-on" lead weights,
available from your hobby dealer.

*lf possible, first attempt to balance the model by
changing the position of the receiver and battery. If
you are unable to obtain good balance by doing so,
then

it will be necessary to add weight to the nose

or tail to achieve the proper balance point.

FINAL CHECKS

proper direction as illustrated in the following
sketches.

RADIO SET-UP

FOUR CHANNEL AIRCRAFT

Transmitter

Stick Movement

Control Surface

Movement

Elevator moves up

Right aileron moves
UP and Left aileron
moves DOWN

Rudder moves

LEFT

Carburetor wide open

See

the

following page for 3 channel set up.

2. Adjust your pushrod hookups as necessary to

provide the proper control surface movements as

listed on page 34. Make sure all of the clevises are

securely "snapped" together.

*NOTE: These control surface "throws" are
approximate and provide a good starting point
for the first flights with your Sierra. You may wish
to change the throws slightly to provide the

smoothness or quickness that you prefer.

1. Make sure the control surfaces move in the

38

RADIO SET-UP

THREE CHANNEL AIRCRAFT

Transmitter

Stick Movement

Control Surface

Movement

Elevator moves up

Rudder moves right

Carburetor wide open

3. Make sure none of the pushrods are binding.

4. Make sure all of the screws and bolts on your
model are tight. Check to see that all of the servos
are secure and all of the servo wheels are screwed
on firmly.

PRE-FLIGHT

CHARGE THE BATTERIES

Follow the battery charging procedures in your radio

i

nstruction manual. You should always charge your

transmitter and receiver batteries the night before
you go fly i ng, and at other times as recommended by
the radio manufacturer.

FIND A SAFE PLACE TO FLY

The best place to fly your R/C model is an AMA
(Academy of Model Aeronautics)-chartered club field.
Ask your hobby shop dealer if there is such a club in
your area and join. Club fields are set up for R/C
flying, which makes your outing safer and more
enjoyable. The AMA can also tell you the name of a
club in your area. We recommend that you join the
AMA and a local club so you can have a safe place
to fly and also have insurance to cover you in case
of a flying accident. (The AMA address is listed on
the front cover of this instruction book).

If a club and its flying site are not available, you
need to find a large, grassy area at least 6 miles away
from any other R/C radio operation, like R/C boats
and R/C cars, and away from houses, buildings and
streets. A schoolyard may look inviting, but it is too
close to people, power lines and possible radio
interference.

GROUND CHECK THE MODEL

If you are not thoroughly familiar with the opera­tion of R/C models, ask an experienced modeler to
check to see that you have the radio installed cor­rectly and that all the control surfaces do what they
are supposed to. The engine operation must also be
checked and the engine "broken in" on the ground by
running the engine for at least two tanks of fuel.

Follow the engine manufacturer's recommenda­tions for break-in. Check to make sure all screws

remain tight, that the hinges are secure and that the

prop is on tight.

RANGE CHECK YOUR RADIO

Wherever you do fly, you need to check the
operation of the radio before each flight. This means
with the transmitter antenna collapsed and the re­ceiver and transmitter on, you should be able to walk
at least 100 feet away from the model and still have
control. Have someone help you. Ask them to stand
by your model and, while you work the controls, tell
you what the various control surfaces are doing.

Repeat this test with the engine running at
various speeds with an assistant holding the model.

If the control surfaces are not acting correctly at all

times, do not fly! Find and correct the problem first.

NOTE: ATTACH A RUBBER BAND-ON WING
WITH A MINIMUM OFTEN #64 RUBBER BANDS.

ENGINE SAFETY

PRECAUTIONS

NOTE: Failure to follow these safety precau-

tions may result in severe injury to yourself and
others.

Keep all engine fuel in a safe place, away from
high heat, sparks or flames, as fuel is very flam­mable. Do not smoke near the engine or fuel.
Remember that the engine exhaust gives off a great
deal of deadly carbon monoxide; therefore, do not

run the engine in a closed room or garage.

Get help from an experienced pilot when learn­ing to operate engines.

Use safety glasses

when starting or running

engines.

39

Do not run the engine in an area with loose
gravel or sand, as the propeller may throw such
material in your face or eyes.

Keep your face and body as well as all specta-

tors away from the plane of rotation of the propeller

as you start and run the engine.

Keep items such as these away from the prop:
loose clothing, shirt sleeves, ties, scarfs, long hair or
loose objects (pencils, screw drivers) that may fall
out of shirt or jacket pockets into the prop.

Use a "chicken stick" device or electric starter;
follow instructions supplied with the starter or stick.
Make certain the glow plug clip or connector is
secure so that it will not pop off or otherwise get into
the running propeller.

Make all engine adjustments from behind the
rotating propeller.

The engine gets hot! Do not touch it during or
after operation. Make sure fuel lines are in good
condition so fuel is not leaked onto a hot engine
causing a fire.

To stop the engine, cut off the fuel supply by

closing off the fuel line or following the engine

manufacturer's recommendations. Do not use hands,

fingers or any body part to try to stop the engine. Do

not throw anything into the prop of a running engine.

AMA SAFETY CODE

Read and abide by the following Academy of Model

Aeronautics Official Safety Code:

GENERAL

1. I will not fly my model aircraft in competition or in

the presence of spectators until it has been proven
to be airworthy by having been previously success­fully flight tested.

2. I will not fly my model aircraft higher than
approximately 400 feet within 3 miles of an airport
without notifying the airport operator. I will give right
of way to, and avoid flying in the proximity of, full
scale aircraft. Where necessary, an observer shall
be utilized to supervise flying to avoid having models
fly in the proximity of full scale aircraft.

3. Where established, I will abide by the safety rules
for the flying site I use, and I will not willfully and
deliberately fly my models in a careless, reckless
and/or dangerous manner.

RADIO CONTROL

1. I will have completed a successful radio equip­ment ground check before the first flight of a new or
repaired model.

2. I will not fly my model aircraft in the presence

of
spectators until I become a qualified flyer, unless
assisted by an experienced helper.

3. I will perform my initial turn after take off away from
the pit, spectator and parking areas, and I will not
thereafter perform maneuvers, flights of any sort or
landing approaches over a pit, spectator or parking
area.

FIRST FLIGHTS

The Top Flite Sierra is a great flying airplane that
flies smoothly and predictably. It is a primary trainer
with a very gentle stall and excellent self-recovery

characteristics. For your best chance at complete
success, we strongly recommend you seek the
assistance of a competent R/C pilot to help you with
your first flights. It is possible to teach yourself to fly,
but why subject your plane to an unnecessary risk?

One technique people often use to familiarize
themselves with the model's controls is to drive the
airplane around on the ground. This can be helpful
for modelers with virtually no previous R/C experi-

ence but you must be careful. If you "drive" it without
the wing mounted and it tips up, the aircraft is likely
to flip all the way over and become scuffed. If you

drive it around with the wing on , a sudden gust of

wind may lift the model into the air before you are

ready. In any case, make sure you have the ability

to "kill" the engine with the throttle trim on the

transmitter and keep the speeds low.

One thing to keep in mind with R/C models
(whether it be cars, boats, or planes) is that the
steering controls may seem to "reverse" when the

model is moving toward you. For example, if you are

flying toward yourself, and you give a right control

input (ailerons or rudder), the model will move off to
your left. The fact of the matter is, of course, that the
controls are not reversed and the aircraft did actually
enter a right turn. The plane does move off to your

left from your vantage point, but if you imagined
yourself in the cockpit you would realize the plane
turned to the right as commanded. All it takes is a

little practice to maintain proper orientation of your

aircraft, but that is why we recommend finding an

instructor.

Before going to the field, make sure you have
charged your batteries and have done all the other
checks described in the manual. Break in the engine
following the manufacturer's instructions. This usu­ally involves running a couple of tanks of fuel through
the engine prior to flying. Run the engine set a little

rich for the first few flights in order to finish the break­in process.

40

TAKE OFF

If you have dual rates on your transmitter, set the
switches to "high rate" for take off, especially when
taking off in a crosswind. For your first flights, it is

best to pick a day when the wind is light, and coming
down the runway. The Sierra handles crosswinds
better than most other trainers, but you do not want
to complicate yourfirstflights. Remember, you should
always take off into the wind. Although the Sierra
has good low speed characteristics, you should build
up some extra speed before lifting off, as this will give
you a safety margin in case of a "flame-out." When
the plane has sufficient flying speed, lift off by
smoothly applying a little up elevator (don't "jerk" it
off into a vertical climb!), and climb out gradually. Let
your Sierra climb into the wind, making only minor
corrections to keep it going straight until it is at a
comfortable altitude. Then make a gradual turn.

The Sierra will climb out at a 20 or 30 degree
angle under full throttle. It is designed to fly level with
neutral elevator trim at approximately 1/2 to 2/3
throttle. This is the best speed for learning to fly. On

later flights, if you want the Sierra to maintain level
flight atfull throttle, you will need to give ita little down
trim.

FLYING

We recommend that you take it easy with your
Sierra for the first several flights and gradually "get
acquainted" with this great plane as your engine
becomes fully broken-in. Your first flights should
consist of mostly gentle turns. These will give you
practice at coordinating your control inputs and
maintaining the proper orientation of the airplane.

channel airplane), then gently giving some back
stick (up elevator). Enough back stick should be held
in to keep the aircraft at a constant altitude. When
you wish to stop turning, apply opposite aileron (or
rudder) to level the wings. Then release the sticks.
When you are comfortable flying the aircraft, you
can practice using the rudder along with the ailerons
to "coordinate" the turns. Usually, a small amount of

rudder applied in the direction of the turn will keep the

tail following in the exact same track as the nose.

Add and practice one maneuver at a time, learning
how your Sierra behaves in each one. For ultra­smooth flying and normal maneuvers, we recom­mend using the "low rate" settings as listed on page

34. High rate control throws will give your Sierra
enough control for loops, barrel rolls, axial rolls, and
many other basic aerobatic maneuvers.

After you have several flights on your Sierra, it's
time to reward yourself with your first aerobatic
maneuver. A loop is a good choice. Climb to a safe
altitude and turn into the wind. Lower the nose with
a little down elevator into about a 5 degree dive and
apply full throttle. After you dive for a couple of
seconds, slowly pull back on the elevator stick to
about 1/2 to 3/4 up elevator (depending on your
throws). Hold this control input. After you "go
around the top" and start down the back side of the

loop, pull the throttle back to about half. This will
keep the stresses on the airplane low and the airspeed
relatively constant. Keep holding the up elevator
until the plane is nearly level. Then slowly release

the sticks. Your done!!! It's really that easy!

CAUTION (THIS APPLIES TO ALL R/C AIR-

PLANES): If, while flying, you notice any

unusual sounds, such as a low-pitched "buzz,"
this may be an indication of control surface
"flutter." Because flutter can quickly destroy
components of your airplane, any time you
detect flutter you must immediately cut the
throttle and land the airplane! Check all servo

grommets for deterioration (this will indicate

which surface fluttered), and make sure all

pushrod linkages are slop-free. If it fluttered

once, it will probably flutter again under similar

circumstances unless you can eliminate the

slop or flexing in the linkages. Here are some

things which can result in flutter: Excessive

hinge gap; not mounting control horns solidly;

sloppy fit of clevis pin in horn; elasticity present

in flexible plastic pushrods; side-play of push-

rod in guide tube caused by tight bends; sloppy

fit of Z-bend in servo arm; insufficient glue used

when gluing in the elevator joiner wire or aileron

torque rod; excessive flexing of aileron, caused

by using too soft balsa aileron; excessive "play"

or "backlash" in servo gears; and insecure

servo mounting.

Turns are accomplished by banking the aircraft

with the ailerons (rudder will accomplish this on a 3-

41

LANDING

When it's time to land, fly a normal landing
pattern and approach as follows. Reduce the power
to about 1/3 and fly a downwind leg far enough out
from the runway to allow you to make a gentle 180
degree turn. As you make the turn into the wind for
yourfinal approach, pull the throttle back to idle. The

Sierra has a lot of lift, so you will need a quite slow,
reliable idle in order to achieve a nice, slow landing.
Allow the plane to keep descending on a gradual
"glide slope" until you are about 4 feet off the runway.
Gradually apply a little up elevator to "flare" for
landing. You should apply just enough up elevatorto
hold the plane just off the runway while a portion of
the excess speed bleeds off. The Sierra should
settle onto the runway for a slow, slightly nose high
landing.

Have a ball! But always stay in control and fly

in a safe manner.

GOOD LUCK AND

HAVE FUN FLYING!

LANDING APPROACH

APPROACH TOO STEEP

TOO MUCH FLARE

APPLY UP ELEVATOR!

DANGER OF STALLING!

RELEASE ELEVATOR.

GOOD LANDING FLARE

HOLD THIS ANGLE

UNTIL TOUCHDOWN

42

Make sure radio batteries are all charged. We
suggest checking the batteries with a ESV Meter
to make sure they are fully charged.

Make sure the transmitter and receiver are

on the

same frequency.

Glow plug driver to power the glow plug.

Fuel and fuel pump or fuel bulb. A good quality

10-15% nitro fuel is recommended.

Extra props and a prop wrench

Screwdrivers, knife, pliers, and wrenches

Epoxy and something to mix it on, A thick

CA and

accelerator.

Paper towels

Cleaner to remove

fuel residue from the plane.

Extra glow plugs

"Chicken stick"

or electric starter and 12 volt

battery.

Wing bolts or #64

rubber bands.

Fuselage, Wing

Transmitter

AMA license

Remove all excess fuel from the fuel tank,
as this fuel can become jelly-like and cause
clogging of fuel lines, as well as clogging
the engine's carburetor.

Always use after-run

oil in the

engine to

prevent corrosion.

Check and double check that the transmit­ter and receiver switches are switched to
the off positions.

Wipe off the excess oil that will collect on
the wing and fuselage. Use a light-duty
cleaner to help cut through the oil.

Remove fresh fuel from the surface of the

plane immediately, as different brands can
cause clouding of the surface.

Replace any bent, marred or dinged props
as they can fly apart at any time when the
engine is running.

Completely check the airplane for damage

to

the wings, landing gear and covering.

Repair as needed before your next flight.

BUILDING NOTES.

Kit Purchase Date
Where Purchased
Price
Date Construction Started
Date Construction Finished
Date of First Flight
Finished Weight

Comments

TRANSPORTING CHECKLIST

AFTER-FLIGHT MAINTENANCE

43

SIERRA PARTS LIST

PART# QTY. DESCRIPTION
PACKED LOOSE IN KIT

MM40D 1 .40 SIZE ENGINE

MOUNT (DRILLED)

PLTB011 3 24" PLASTIC OUTER

PUSHROD TUBE
SIE4D01 1 SIERRA DECAL SHEET
SIE4F05 2 PLYWOOD DC FUSELAGE

DOUBLER
SIE4P01 1 SIERRA FUSE PLAN SHEET
SIE4P02 1 SIERRA WING PLAN SHEET
SIE4P03 1 INSTRUCTION BOOK
SIE4R04 1 BALSA 1/4" FIN POST
SIE4W12 2 15/32x1-5/8x11-1/5

TAPERED WING TIP
WIRES10 1 .074 X 36" WIRE

THREADED

BOTH ENDS
WIRES17 2 .074 X 34" WIRE THREADED

ONE END

SIE4AQ1 1 SUB-PACK. DIE-CUT BALSA

FUSELAGE PARTS

SIE4F06 2 BALSA 1/8" DC AFT

FUSELAGE SIDE
SIE4F07 2 BALSA 1/8" DC UPPER

FWD

FUSELAGE SIDE

SIE4F08 2 BALSA 1/8" DC LOWER FWD

FUSELAGE SIDE
SIE4F09 2 BALSA 1/8" DC REAR FUSE DBLR.

& FWD FUSE BOTTOM
SIE4F10 1 BALSA 1 /8" DC AFT FUSE TOP
SIE4F11 2 BALSA 1/8" DC MIDDLE FUSE

BOTTOM

SIE4F12 1 BALSA 1/8" DC AFT FUSE BOTTOM

SIE4A02 1 SUB-PACK. DIE-CUT PLYWOOD

FUSELAGE PARTS

SIE4F01 1 PLYWOOD 1/8" DC

F-1A,

F-1 B,

ST.ANDFW

SIE4F02 1 PLYWOOD 1/8" DC F-2,

BW,

AND HATCH PARTS

SIE4F03 1 PLYWOOD 1/8" DC F-3, F4,

F-5, AND GD'S

SIE4AQ3 1 SUB-PACK. DIE-CUT WING PARTS

SIE4W01 1 PLYWOOD 1/8" DC W-1B,

F, A, GUIDE, AIL. ST

SIE4W02 1 PLYWOOD 1/8" DC

DIHEDRAL BRACES

SIE4W04 2 BALSA 1/8" DC W-1A,

W-1B

SIE4W05 1 BALSA 1/16" DC WING

CENTER SHEETS 1,4

SIE4W06 2 BALSA 1/16" DC WING CENTER

SHEETS 2, 3, 5,6
SIE4W15 6 BALSA 3/32" DC RIBS W-3*
*MAY SUBSTITUTE (8) W03'S

SIE4A04 1 SUB-PACK. SHAPED BALSA

TAIL PARTS

SIE4S01 1 BALSA 1/4" STAB FORWARD
SIE4S02 1 BALSA 1/4" STAB AFT
SIE4S03 1 BALSA TAPERED ELEVATOR

SIE4A05 1 SUB-PACK. LONG WING PARTS

SIE4W07 4 BALSA 3/8" X 3/8" X 30" SPARS
SIE4W08 2 BALSA 30" TAPERED AILERON
SIE4W09 1 BALSA 30" SHAPED AND

NOTCHED LE PAIR

SIE4W10 1 BALSA 30" SHAPED AND

NOTCHED TE PAIR

SIE4A06 1 SUB-PACK. SHAPED

VERTICAL FIN PARTS
SIE4R02 1 BALSA 1/4" FIN FORWARD
SIE4R03 1 BALSA 1/4" FIN AFT
SIE4R05 1 BALSA 1/4" RUDDER

SIE4A07 1 SUB-PACK. SMALL WOOD PARTS

DOWEL020 2 DOWEL 1/4" DIA. X 5-1/8"
SIE4F13 1 PLYWOOD 1/4" WING BOLT PLATE
SIE4F14 2 PLYWOOD 1/8" LG ALIGN STRIPS
SIE4F15 1 PLYWOOD 9mm ENGINE

SPACER PLATE

SIE4F16 1 PLYWOOD 1/8" LANDING

GEAR PLATE
SIE4R01 1 BALSA 1/4" DORSAL FIN
SIE4W11 2 BALSA GROOVE CENTER

TE PIECE
SIE4W14 1 PLYWOOD 1/16" TRAILING

EDGE PLATE

SIE4W09 1 SUB-PACK. SHEAR WEBS

SIE4 26 BALSA 1/16"

SHEAR WEBS

SIE4M01 1 SUB-PACK. HARDWARE

NUTS001 4 4-40 BLIND NUT
NYLON03 2 SMALL NYLON CONTROL

HORN
NYLON13 2 1/4--20X 2" NYLON BOLT
NYLON16 1 NYLON STEERING ARM
NYLON17 4 NYLON CLEVIS
NYLON20 2 NYLON SWIVEL

NYLON21 2 NYLON SWIVEL CLEVIS

NYLON36 1 FLAT NYLON LG STRAP
SCRW002 4 2-56X5/8" MACHINE SCREW
SCRW003 4 440 X 1" MACHINE SCREW
SCRW005 1 6-32 X 1/8" SOCKET SET SCREW
SCRW020 1 6-32X1/4" MACHINE SCREW
SCRW024 6 #2 X 3/8" SHEET METAL SCREW
WBNT002 1 3/32" AIL. TORQUE RODS L & R
WBNT101 1 1/8" ELEVATOR JOINER WIRE
WHCL015 2 5/32" WHEEL COLLAR
WSHR005 4 #4 FLAT WASHER

SCRW018 4 #6 X 3/4" SHEET METAL SCREW

SIE4M02 1 SUB-PACK. LARGE HARDWARE

PLTB004 1 6-1/2" PLASTIC INNER

SPACER TUBE
WBNT163 2 5/32" MAIN LANDING GEAR
WBNT164 1 5/32" NOSE GEAR
WIRES16 2 .074X12" WIRE THREADED

ONE END

44

SIERRA TWO-VIEW

DRAWING