Great Planes GPMA1311 User Manual

WARRANTY

Great Planes Model Manufacturing Co. guarantees this kit to be free from defects in both material and workmanship
at the date of purchase. This warranty does not cover any component parts damaged by use or modification. In no case
shall Great Planes’ liability exceed the original cost of the purchased kit. Further, Great Planes reserves the right
to change or modify this warranty without notice.

In that Great Planes 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 buyers are not prepared to accept the liability associated with the use of this product, they are advised
to return this kit immediately in new and unused condition to the place of purchase.

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

GPMZ0215 V1.0 Entire Contents © Copyright 1999

P.O. Box 788 Urbana, IL 61801 [phone]

[e-mail]

INSTRUCTION MANUAL

QQUUAARRTTEERR SSCCAALLEE

A.R.F.

Almost Ready to Fly

Important Safety Precautions . . . . . . . . . . . . . . . . . . . 2

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Decisions You Must Make . . . . . . . . . . . . . . . . . . . . . . 3

Engine Selection. . . . . . . . . . . . . . . . . . . . . . . . 3

Preparations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Required Accessories . . . . . . . . . . . . . . . . . . . . 3

Building Supplies and Tools. . . . . . . . . . . . . . . . 3

Optional Supplies and Tools . . . . . . . . . . . . . . . 4

General Inspection . . . . . . . . . . . . . . . . . . . . . . 4

Inch/Metric Ruler. . . . . . . . . . . . . . . . . . . . . . . . 4

Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Begin Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Fuelproof the Fuselage . . . . . . . . . . . . . . . . . . . 6

Join the Wing Halves . . . . . . . . . . . . . . . . . . . . 6

Mount the Engine . . . . . . . . . . . . . . . . . . . . . . . 6

Install the Fuel Tank . . . . . . . . . . . . . . . . . . . . . 8

Mount the Wing. . . . . . . . . . . . . . . . . . . . . . . . . 9

Mount the Stab & Fin . . . . . . . . . . . . . . . . . . . 10

Install the Tail Landing Gear . . . . . . . . . . . . . . 11

Install the Main Landing Gear . . . . . . . . . . . . . 12

Install the Elevator Joiner Wire . . . . . . . . . . . . 13

Join The Control Surfaces . . . . . . . . . . . . . . . . 14

Hook up the Ailerons. . . . . . . . . . . . . . . . . . . . 15

Radio Installation . . . . . . . . . . . . . . . . . . . . . . 16

Pushrod Installation. . . . . . . . . . . . . . . . . . . . . 17

Throttle Pushrod Installation . . . . . . . . . . . . . . 18

Final Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Windshield Installation. . . . . . . . . . . . . . . . . . . 19

Strut Installation . . . . . . . . . . . . . . . . . . . . . . . 19

Control Throw Adjustment. . . . . . . . . . . . . . . . 21

Balance the Model Laterally . . . . . . . . . . . . . . 21

Preflight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Charge the Batteries . . . . . . . . . . . . . . . . . . . . 22

Balance the Propeller . . . . . . . . . . . . . . . . . . . 22

Find a Safe Place to Fly . . . . . . . . . . . . . . . . . 22

Ground Check the Model . . . . . . . . . . . . . . . . 22

Range Check Your Radio . . . . . . . . . . . . . . . . 22

Engine Safety Precautions . . . . . . . . . . . . . . . 23

AMA Safety Code (excerpt) . . . . . . . . . . . . . . . . . . . . 23

General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Radio Control . . . . . . . . . . . . . . . . . . . . . . . . . 23

Flying . . . . . . . . . . . . . . . . . . . . . . . . . . . . Back Cover

Takeoff . . . . . . . . . . . . . . . . . . . . . . . Back Cover

Flight. . . . . . . . . . . . . . . . . . . . . . . . . Back Cover

Landing. . . . . . . . . . . . . . . . . . . . . . . Back Cover

Engine Mount Template . . . . . . . . . . . . . . . Back Cover

Your Piper Cub ARF is not a toy, but rather a sophisticated,
working model that functions very much like an actual
airplane. Because of its realistic performance, the Piper Cub
ARF, if not assembled and operated correctly, could possibly
cause injury to yourself or spectators and damage property.

To make your R/C modeling experience totally enjoyable, we
recommend that you get experienced, knowledgeable help
from an instructor with assembly and during your first flights.
You’ll learn faster and avoid risking your model before you’re
truly ready to solo. Your local hobby shop has information
about flying clubs in your area whose membership includes
qualified instructors. You may also contact the national
Academy of Model Aeronautics (AMA), which has more
than 2,500 chartered clubs across the country. Contact the
AMA at the address or toll-free phone number below.

Academy of Model Aeronautics

5151 East Memorial Drive

Muncie, IN 47302-9252

Tele. [phone]

Fax [phone]

or via the Internet at http://www.modelaircraft.org

1. Assemble the plane according to the instructions. Do not
alter or modify the model, as doing so may result in an
unsafe or unflyable model.

2. Take time to align the components straight and true.

3. Use an R/C radio system that is in first-class condition,
and a correctly-sized engine and components (fuel tank,
wheels, etc.) throughout your assembly process.

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

5. You must check the operation of the model before every
flight to ensure that all equipment is operating and that the
model has remained structurally sound. Be sure to check
nylon clevises or other connectors often and replace them if
they show signs of wear or fatigue.

PRECAUTIONS

PROTECT YOUR MODEL,YOURSELF

& OTHERS...FOLLOW THIS

IMPORTANT SAFETY PRECAUTION

TABLE OF CONTENTS

2

Remember: Take your time and follow directions to end
up with a well-built model that is straight and true.

Please inspect all parts carefully before starting to
build! If any parts are missing, broken or defective, or if
you have any questions about assembling or flying this
airplane,
please call us at [phone] or e-mail us at
[e-mail]. If you are calling for
replacement parts, please reference the part name and
number (See page 5) and have them ready when calling.

The Great Planes Piper Cub ARF is an easy-to-fly
sport-scale airplane that closely resembles the full size
Piper Cub both in appearance and performance. The Piper
Cub ARF is very stable and predictable, allowing even
novice skill level pilots to enjoy it.

Because of its docile flight characteristics, this airplane could
be used as a first airplane for learning to fly, but only with the
assistance and close supervision of a competent instructor.
This airplane lacks the self-recovery characteristics of a true
“basic trainer” such as the Great Planes PT

™

series, which is

the model of choice for learning to fly.

Items in parentheses (OSMG2691) are suggested part
numbers recognized by distributors and hobby shops and
are listed for your ordering convenience. GPM is the Great
Planes

®

brand, TOP is the Top Flite®brand, and HCA is the

Hobbico®brand.

❏ 4 Channel Radio with 5 Servos
❏ “Y” Harness For Aileron Servos
❏ Two 6" Servo Extensions For Aileron Servos
❏ Engine – See Engine Selection
❏ Spare Glow Plugs (O.S. #8 For Most 2-Stroke Engines,

OSMG2691) Type F for 4-stroke (OSMG2692)

❏ Propeller (Top Flite

®

Power Point®)

(Refer To Your Engine’s Instructions For Proper Size)

❏ 3’ Medium 3/32" Fuel Tubing (GPMQ4131)
❏ 1/4" Latex Foam Rubber Padding (HCAQ1000)
❏ Fueling System (Great Planes Top Fueler

™

, GPMQ4160)

❏ 8-32 Tap & #29 Drill Bit (GPMR8103)

These are the building tools that are required. We recommend
Great Planes Pro

™

CA and Epoxy glue.

❏ 2 oz. Pro CA (Thin, GPMR6003)
❏ 2 oz. Pro CA+ (Medium, GPMR6009)
❏ CA Accelerator (GPMR6035)
❏ 6-Minute Pro Epoxy (GPMR6045)
❏ 30-Minute Pro Epoxy (GPMR6047)
❏ Canopy Glue (JOZR5007)
❏ Hobby Knife (HCAR0105) & Blades (HCAR0311)
❏ Builders Triangle Set (HCAR0480)
❏ Masking Tape (TOPR8018)
❏ Slip-Joint & Needle Nose Pliers
❏ Monofilament String For Stabilizer Alignment
❏ Screwdrivers (Flat Blade & Phillips)
❏ Pro Thread Locking Compound (GPMR6060)
❏ Isopropyl Alcohol (70%)
❏ Drill & Drill Bits: 1/16" [1.6mm], 5/64" [2mm], 3/32"

[2.4mm], 3/16" [4.8mm], 7/32" [5.6mm], 1/4" [6mm], #29

❏ Top Flite Trim Seal Tool

™

(TOPR2200)

❏ Panel Line Pen (TOPQ2510)
❏ Sandpaper: 80, 220 & 320-grit
❏ Metal File
❏ 3/4 Oz. Fiberglass cloth (HCAR5000)
❏ Paper Towels
❏ T-Pins (HCAR5100)
❏ 1/4-20 x 1" Steel Bolt & 1/4" Washer
❏ Hobby Heat

™

Micro Torch (HCAR0750)

❏ Silver Solder (GPMR8070)
❏ Razor Saw
❏ Petroleum Jelly

Building Supplies and Tools

Required Accessories

PREPARATIONS

Engine Selection

There are several engines that will work well in your Piper
Cub ARF. We recommend an O.S.®FS-70 4-stroke for the
best scale appearance and sound for your Piper Cub. A hot
2-stroke such as an O.S. .46FX or SuperTigre®G45 would
also be a good choice. Another option for a 2-stroke would
be a mild .60, such as the O.S. .65 LA or O.S. .60 FP. Your
choice of 2-stroke or 4-stroke will determine the location of
the throttle servo and throttle pushrod exit on the firewall, so
plan ahead.

DECISIONS YOU MUST MAKE

INTRODUCTION

NOTE: We, as the manufacturer, provide you with a top

quality kit and great instructions, but ultimately the quality of
your finished model depends on how you assemble 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.

3

4

❏ CG Machine

™

(GPMR2400)

❏ Dremel®MultiPro™Or Similar W/Cut-Off Wheel
❏ Dead Center™Engine Mount Hole Locator (GPMR8130)
❏ Groove Tube™Grooving Tool (GPMR8140)
❏ Curved Tip Canopy Scissors (HCAR0667)
❏ Switch and Charge Jack (GPMM1000)
❏ 6 Oz. Segmented lead weight (GPMQ4485)

Eliminate any wrinkles you find in the covering by shrinking
them away with a low temperature setting on a heat gun, then
apply pressure to the area with a covering iron and a hot
sock. This will securely bond the covering to the wood so the
wrinkles will be less likely to reappear in the future.

AMA =

Academy of Model Aeronautics

ARF = almost ready to fly

Deg = degrees Elev = elevator

Fuse = fuselage " = inches

LE = leading edge Ply = plywood

Stab = stabilizer TE = trailing edge

LG = landing gear mm = millimeters

1/64" = .4mm
1/32" = .8mm
1/16" = 1.6mm
3/32" = 2.4mm

1/8" = 3.2mm
5/32" = 4mm
3/16" = 4.8mm

1/4" = 6.4mm

3/8" = 9.5mm

1/2" = 12.7mm

5/8" = 15.9mm

3/4" = 19mm

1" = 25.4mm
2" = 50.8mm
3" = 76.2mm

6" = 152.4mm
12" = 304.8mm
15" = 381mm
18" = 457.2mm
21" = 533.4mm
24" = 609.6mm
30" = 762mm
36" = 914.4mm

1" = 25.4mm (conversion factor)

Metric Conversions

Common Abbreviations

General Inspection

Optional Supplies and Tools

5

Key# Description Qty

1 Fuselage . . . . . . . . . . . . . . . . . . .1

2 Left Wing Panel w/Aileron . . . . . . .1

3 Right Wing Panel w/Aileron . . . . . .1

4 Cowl . . . . . . . . . . . . . . . . . . . . . . .1

5 Decals . . . . . . . . . . . . . . . . . .1 Set

6 Side Windows . . . . . . . . . . . . . . . .2

7 Canopy . . . . . . . . . . . . . . . . . . . .1

8 Right Landing Gear Cover . . . . . .1

9 Left Landing Gear Cover . . . . . . .1

10 Landing Gear . . . . . . . . . . . . . . . .1

11 Wing Bolt Plate . . . . . . . . . . . . . . .1

12 Stabilizer . . . . . . . . . . . . . . . . . . .1

13 Elevator Assembly . . . . . . . . . . . .1

14 Rudder . . . . . . . . . . . . . . . . . . . . .1

15 Vertical Fin . . . . . . . . . . . . . . . . . .1

16 Tail Wheel Assembly . . . . . . . . . . .1

17 Tail Wheel Bracket . . . . . . . . . . . .1

18 Wing Struts . . . . . . . . . . . . . . . . .2

19 Elevator Joiner Wire . . . . . . . . . . .1

20 Dummy Engine . . . . . . . . . . . . . . .1

21 Wing Joiners . . . . . . . . . . . . . . . .3

22 Landing Gear Fairing Mounts . . . .2

23 Wing Dowels . . . . . . . . . . . . . . . .2

24 Pushrods . . . . . . . . . . . . . . . .1 Set

Parts Not Shown In Photo

Description Qty

Adjustable Engine Mount . . . . . . . . . . . . .1

Main Wheels . . . . . . . . . . . . . . . . . . . . . .2

Servo Tray . . . . . . . . . . . . . . . . . . . . . . . .1

CA Hinge Strip (2" x 9") . . . . . . . . . . . . . .1

Hardware Bag . . . . . . . . . . . . . . . . . . . . .1

Replacement Parts

If needed, replacement parts for Piper Cub ARF are
available through your hobby supplier.

Wing Set . . . . . . . . . . . . . . . . . . . . .GPMA2180

Fuselage Kit . . . . . . . . . . . . . . . . . . .GPMA2181

Tail Fin Set . . . . . . . . . . . . . . . . . . . .GPMA2182

Canopy . . . . . . . . . . . . . . . . . . . . . .GPMA2183

Cowl . . . . . . . . . . . . . . . . . . . . . .GPMA2184

Landing Gear Set . . . . . . . . . . . . . . .GPMA2185

1

2

3

4

5

7

8

9

10

10

11

12

13

14

15

16

17

18

18

19

20

21

22

23

24

6

6

❏ 1. Coat the firewall and all other bare wood around the
firewall with fuelproof paint or 30-minute epoxy thinned with
alcohol. Fuelproof other areas of bare wood in the fuselage
that may be exposed to fuel or engine exhaust, such as the
fuel tank area and the front and back of the wing saddle.

❏ 2. Set the fuselage aside while the paint or epoxy dries.

❏ 1. Cut the covering 1/8" inside the edges of the opening

in the bottom of the Right Wing Panel for the aileron servo.
Use your Top Flite MonoKote

®

Trim Seal Tool™to seal the

covering to the sides of the opening.

Note: You’ll notice a piece of string that passes through the
covering at the location of the aileron servo. Don’t remove
the string because you will use it to pull your aileron servo
cord through the wing later.

❏ 2. Use 30-minute epoxy to glue the two 1/8" x 1-1/8" x
5-1/4" [3mm x 28mm x 133mm] plywood Wing Joiners and
the 3/32" x 1-1/8" x 5-1/4" [2.4mm x 28mm x 133mm]
plywood wing joiner together. Wipe away any excess epoxy.

❏ 3. Test fit the wing halves with the wing joiner. If necessary,
sand any high spots on the root end of the wing panels so
there is no gap when you join them. Since the wing is built
with no dihedral, it can be built flat on your work surface.

Make a

dry run

of the following step

without using any glue

so you will know how to clamp your wing together.

❏ 4. Tape a piece of wax paper or plan protector over your
work surface. Thoroughly coat the joiner pockets and the
mating ends of both wing halves with 30-minute epoxy. Set
the wing halves aside and proceed quickly. Coat all surfaces
of one half of the wing joiner with 30-minute epoxy and
place it in one of the wing halves. Coat the other half of the
joiner with 30-minute epoxy and join the other wing. Use a
piece of balsa or cardboard to wipe away excess epoxy. Use
masking tape to tightly tape the wing together. Use a tissue
dampened with alcohol to wipe away any more epoxy that
oozes out of the wing, then set the wing aside. Do not
disturb the wing until the epoxy has fully cured.

❏ 1. Cut or break the “spreader bar” from each Engine
Mount half. Carefully trim any extra material left by the

spreader bar from each mount half. The surfaces where the
spreader bars were attached must be smooth to allow the
mount halves to fit together. Trim the flashing off any rough
edges if necessary.

Mount the Engine

Join the Wing Halves

Fuelproof the Fuselage

BEGIN CONSTRUCTION

❏ 2. Extend the marks on the firewall to locate the position
for the engine mount on the firewall.

❏ 3. Cut the Engine Mount Template from the back cover
of the manual and tape it to the firewall as shown. At the
locations on the template, drill four 7/32" [5.6mm] holes in
the firewall for the engine mount blind nuts.

❏ 4. Install four 8-32 Blind Nuts to the inside of the firewall.
Pull the blind nuts into the back side of the firewall using
8-32 Socket Head Cap Screws with a flat washer under
the head of the screws. Fit the two halves of the Engine
Mount together. Use four #8 Flat Washers and four 8-32 x
1" Socket Head Cap Screws to secure the engine mount to
the firewall. Do not tighten the screws at this time, as the
mount must be adjusted for the engine. Depending on your
engine selection, it may be necessary to trim the top center
stringer to allow for positioning the engine mount.

❏ 5. Test fit your engine into the mount. Adjust the width of
the rails to fit the engine snugly. Tighten the mount screws
to allow marking the engine mounting holes without moving
the rails.

❏ 6. Position the engine on the engine mount rails so the
propeller thrust washer is 5-1/4" [133mm] ahead of the
firewall. Use a Great Planes Dead Center Hole Locator
(GPMR8130) (not included) or a sharpened piece of wire to
scribe the four engine mount holes onto the rails. Use a
center punch at the marks to prevent the drill bit from
wandering, then drill #29 pilot holes through the rails. Be
sure to hold the drill perpendicular to the rails. If you have
access to a drill press, this is a good tool for this purpose.
Use an 8-32 tap to tap the holes for the 8-32 screws. Use
four 8-32 x 1" socket head cap screws to secure the engine
to the mount.

❏ 7. Drill a 3/16" [4.7mm] hole in the firewall for the throttle
pushrod. The hole location will depend on whether you are
installing a 2-stroke or 4-stroke engine.

❏ 8. Roughen the outside surface of the 11-3/4" [298mm]
Throttle Pushrod Tube with coarse grit sandpaper. Insert
the pushrod tube through the hole in the firewall. Push it in
until it is flush with the front of the firewall. Use medium CA
to glue the tube to the firewall, but leave it free inside the
fuselage until the servos are installed.

Note: The engine has been removed from the above picture
for clarity.

7

❏ 9. Slip the Cowl over the front of the fuse. Cut a hole in
the cowl just large enough to accommodate the engine.
After the cowl is mounted, you can enlarge the hole to allow
some clearance for a more finished appearance.

❏ 10. Align the front of the cowl 1/8" [3mm] behind the drive
washer of the engine and tape it to the fuselage.

❏ 11. Drill a 5/64" [2mm] hole through the cowl into the
fuselage. Screw a #4 x 1/2" Sheet Metal Screw through the
cowl just far enough into the fuselage to temporarily hold
that part of the cowl in place. One at a time, drill a hole and
insert a screw into the cowl the same way. Depending on
the engine, you may use either four or five screws to secure
the cowl.

❏ 12. Remove the cowl. Roughen the inside of the cowl
around the screw holes with 80-grit sandpaper. Cut four 1"
square pieces of glass cloth and glue them to the inside of
the cowl over the mounting holes with 30-minute epoxy as
shown in the photo. Set the cowl aside while the epoxy
cures. Use a small amount of epoxy to fuelproof the cowl
mounting blocks.

❏ 1. Cut the clear pick-up tube included with this kit to a
length of 3-3/16" [81mm]. Assemble the fuel tank as shown
in the sketch using the 90-degree nipple. After you
assemble the tank hold it up to the light and make sure the
clunk does not contact the rear of the tank. If necessary,
disassemble the tank and shorten the pick-up tube.

❏ 2. Wrap the tank with 1/4" [6mm] foam rubber secured
with a couple of rubber bands.

❏ 3. Remove the engine mount. Drill 1/4" [6mm] holes
through the firewall for your fuel lines. Make sure to drill the
holes where they will not interfere with the engine mount.

❏ 4. Fit approximately 12" to 14" [300mm to 360mm] of fuel
line on the pick-up and vent nipples of your fuel tank. Pull the
fuel lines through the holes you drilled in the firewall as you
install your tank. Be certain you do not kink the fuel lines.

❏ 5. Mount the muffler to your engine. Trim the cowl where
necessary so it does not interfere with the muffler, allowing
an approximate 1/4" [6mm] clearance all the way around.
Attach the fuel lines from the fuel tank to the engine, making
sure the fuel and pressure lines are correctly attached.

Install the Fuel Tank

8