Dynaflite super decathlon User manual

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DECGP04 Printed in USA
READ THROUGH THE PRELIMINARY INFORMATION BEFORE YOU START
BUILDING. IT CONTAINS IMPORTANT INSTRUCTIONS, WARNINGS, AND
INFORMATION CONCERNING THE BUILDING AND USE OF THIS MODEL.
© 2011 Hobbico®, Inc V:2.0
Instruction Manual
•89” IMAA-legal aerobatic trainer
•Selig 8036 semi-symmetrical airfoil for maneuverability & low-speed stability
•Performance excels with a wide range of engines
WARRANTY
Dynaflite 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 Dynaflite’s liability exceed the original cost of the purchased kit. Further, Dynaflite
reserves the right to change or modify this warranty without notice. In that Dynaflite 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, return this kit
immediately in new and unused condition to the place of purchase.
™

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TABLE OF CONTENTS
INTRODUCTION .................................................2
PRECAUTIONS...................................................3
PREPARATIONS.................................................3
Required accessories ...................................3
Suggested supplies.......................................4
Building notes ...............................................4
Types of wood ..............................................4
Metric conversions ........................................5
DIE PATTERNS...................................................5
BUILD THE TAIL SECTION ................................6
Build the fin and rudder ................................6
Build the stabilizer.........................................7
Build the elevators ........................................7
BUILD THE WING ...............................................8
Sheet the top of the wing............................11
Finish the wing............................................13
Build the ailerons ........................................14
BUILD THE FUSELAGE ...................................15
Assemble the firewall..................................15
Build the bulkheads and fuselage sides ............18
Assemble the fuselage ...............................19
Mount the wing ...........................................21
Sheet the top of the fuselage......................23
Finish the bottom of the fuselage ...............24
Mount the tail ..............................................26
Make and mount the wing struts.................28
Finish the windshield and cowl ...................29
FINAL ASSEMBLY ...........................................30
Install the radio system ...............................30
Set the control throws .................................30
FINISHING ........................................................31
Finishing the struts......................................31
Balance your model ....................................31
PREFLIGHT ......................................................31
Balance your propellers ..............................31
Charge your batteries .................................32
AT THE FLYING SITE .......................................32
Ground check your model...........................32
Range check your radio..............................32
SAFETY PRECAUTIONS .................................32
FLIGHT..............................................................33
Takeoff ........................................................33
Flying ..........................................................33
Landing .......................................................34
INTRODUCTION
Congratulations on your choice of this kit for your
next project. The Super Decathlon is a Fun Scale®
model of a truly classic aerobatic aircraft. It has the
presence that only a big model can deliver. The
full-scale Super Decathlon is a basic aerobatic
aircraft capable of spins, loops, rolls, immelmanns,
split S’s, hammerheads and basic inverted flight.
Super Decathlons have been the choice for basic
aerobatics in the US for the past twenty-five years.
One of the things that made this plane so popular
was the fact that it was one of the easiest landing
taildraggers ever made. The Dynaflite Super
Decathlon has the great landing habits of the full-
scale plane, with more aerobatic potential.
The two-piece wing means transporting this 89"
span model can be done in any vehicle which can
hold the manageable 67" fuselage. The big wing
and strong structure of the Dynaflite Super
Decathlon allows for an engine range from the
1.08 2-stroke all the way up to the 2.1 gas engines.
We do recommend flying wires on the tail if you are
using an engine at the larger end of the
recommended range.
At Dynaflite, we take pride in offering kits that are
simple and straightforward to build and provide
value for your modeling dollar. Because of the size
and cost of this model, we assume you have built
several models and have a general working
knowledge of modeling and its terms. If you HAVE
NOT built and flown several kits, we strongly
recommend you back up and get some experience
before beginning this kit.
YourSuperDecathlonisnotatoy,butasophisticated
working model that functions like a full-size airplane.
Because of its performance, if you do not assemble
and operate the Super Decathlon correctly, you
could possibly injure yourself or spectators and
damage property. To make your R/C modeling
experience totally enjoyable, we recommend that
you get assistance with assembly and your first
flights from an experienced, knowledgeable

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modeler. Your local hobby shop has information
about flying clubs in your area whose membership
includes qualified instructors if needed.
If you are not already a member of the AMA,
please join! The AMA is the governing body of
model aviation and membership provides liability
insurance coverage, protects modelers’ rights and
interests and is required to fly at most R/C sites.
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
IMPORTANT!!!
Two of the most important things you can do to
preserve the radio controlled aircraft hobby are to
avoid flying near full-scale aircraft and avoid flying
near or over groups of people.
PRECAUTIONS
1. You must 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. In a few cases the instructions may differ
slightly from the photos or plan. In those instances,
follow the written instructions.
2. You must take the time to build straight, true
and strong.
3. You must install all R/C and other components
so that the model operates properly on the ground
and in the air.
4. You must test the operation of the model before
the first and each successive flight to insure that all
equipment operates correctly. You must also make
certain that the model has remained structurally
sound.
Please inventory and 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] or you may email us at
[email protected] and we'll be
glad to help. If you are calling for replacement
parts, please look up the part numbers and have
them ready when calling.
PREPARATIONS
REQUIRED ITEMS
These are the items not included with your kit; you
will need to purchase them separately. Items in
parentheses (GPMQ4131) 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 w/6 servos (5 high torque)
❏2 18" Servo extension wires (ailerons)
❏2 “Y” Connectors (ailerons, elevators)
❏Engine: 1.20 - 1.60 4-stroke,
1.08 - 1.8 2-stroke, or 1.5 - 2.1 gas
❏Engine mount and mounting hardware
❏16 - 24 oz. Fuel tank
❏Standard fuel tubing, glow (GPMQ4131)
❏Tygon fuel tubing, gas (DUBQ0427)
❏Gas stopper (DUBQ0675)
❏2 3-1/4" Main wheels (GPMQ4226)
❏1 1-1/2" Tail wheel (GPMQ4243)
❏4 5/32" Wheel collars (GPMQ4306)
❏2 1/8" Wheel collars (GPMQ4304)
❏2 3/16" Axles (GPMQ4278)
❏20 Giant Scale hinges
❏4 8-32 x 1" Socket head bolts (GPMQ3048)
❏4 8-32 Blind Nuts (GPMQ3328)
❏Coverite™Fabric or other covering
(approximately 5 rolls)
❏Paint for fuelproofing, engine cowl and
windows
❏1/4" Latex Foam Rubber (HCAQ1000)
❏3" Spinner (GPMQ4530)
❏1 or 2 1/4 Scale pilot(s) (optional)
(DGAQ2110)
❏Decathlon cockpit kit (optional) (DYFQ8115)

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SUGGESTED SUPPLIES
We recommend Great Planes Pro™CA and Epoxy
❏4 oz. Thin CA Adhesive (GPMR5904)
❏4 oz. Medium CA+ Adhesive (GPMR5910)
❏2 oz. Thick CA- Adhesive (GPMR6015)
❏Pro CA Applicator Tips (HCAR3780)
❏Pro CA Accelerator w/pump (HCAR3750)
❏6-Minute Epoxy (GPMR6045)
❏30-Minute Epoxy (GPMR6047)
❏8 oz. Aliphatic Resin Wood Glue
(GPMR6163)
❏4 oz. Milled Fiberglass (GPMR6165)
❏Microballoon Filler (TOPR1090)
❏
J&Z Products RC/56 Canopy Glue (JOZR5007)
❏Great Planes Plan Protector (GPMR6167)
BUILDING NOTES
• When you see the term “cut and fit” in the
instructions, it means you should first position the
part on the assembly without using any glue.
Slightly modify or shape the part as necessary for
the best fit. Do not glue unless instructed to do so.
• Throughout the assembly of this model, thin CA
should be used unless the step calls for another
type of adhesive. If your parts do not fit well,
substitute medium or thick CA.
• Whenever just “epoxy” is called for, you may use
either 30-minute epoxy or 6-minute epoxy. When
30-minute epoxy is specified, it is highly
recommended that you use only 30-minute epoxy
because you will need either the working time or
the additional strength.
• CA accelerator causes CA glues to react
immediately, but residual accelerator can
prematurely cure CA on nearby joints even
hours later.
• During construction you will be using a number of
balsa sticks to frame various assemblies. Ample
material is included but you should study the
plans, then make an effort to cut the longest
pieces you will need first. Label the pieces for later
reference as you cut them. By doing this now, you
won't have to splice pieces together later.
• Do not throw away any leftover material until after
you have completed your model. Some small
pieces of leftover balsa or plywood are used
during construction.
TYPES OF WOOD

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1/64" = .4 mm
1/32" = .8 mm
1/16" = 1.6 mm
3/32" = 2.4 mm
1/8" = 3.2 mm
5/32" = 4.0 mm
3/16" = 4.8 mm
1/4" = 6.4 mm
3/8" = 9.5 mm
1/2" = 12.7 mm
5/8" = 15.9 mm
3/4" = 19.0 mm
1" = 25.4 mm
2" = 50.8 mm
3" = 76.2 mm
6" = 152.4 mm
12" = 304.8 mm
18" = 457.2 mm
21" = 533.4 mm
24" = 609.6 mm
30" = 762.0 mm
36" = 914.4 mm
DIE PATTERNS
METRIC CONVERSIONS

BUILD THE TAIL SECTION
BUILD THE FIN AND RUDDER
❏1. Cover the FIN/RUDDER PLAN with Great
Planes Plan Protector or wax paper.
❏2. From two 3/8" x 15/16" x 24" balsa sticks, cut,
fit and glue the fin frame as shown in the photo.
Remember to save all leftover pieces.
❏3. From a 3/8" x 1/2" x 30" balsa stick, cut, fit and
glue the upper rear gusset. From leftover 3/8" x
15/16" balsa, cut, fit and glue the other 3 gussets.
❏4. From the 1/8" x 3/8" x 30" balsa stick, cut, fit
and glue the 3 fin ribs in place.
❏5. Remove the fin from the building board.
❏6. If you will be adding flying wires, drill a 5/16"
hole in the bottom of the upper rear gusset. Cut
3/8" off one of the 5/16" x 6-5/8" dowels. Using thin
CA, glue the 3/8" piece in the hole.
❏7. Using a 3/8" x
15/16" x 24" balsa
stick, the 3/8" x 1/2" x
28-1/2" balsa stick
(leftover from the
upper rear gusset)
and a 1/8" x 3/8" x 30"
balsa stick, build the
rudder. Do not forget
the 3/8" x 1/2" gusset
in the lower corner.
❏8. Remove the rudder from the plan. Mark the
centerline the length of the fin trailing edge and the
rudder leading edge. Cut the hinge slots along the
centerlines where shown on the plan.
❏9. Using the fuse plan top view as a reference,
sand the leading edge of the rudder to the “V”
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77
shape shown. Make sure the “V” is large enough to
allow for the specified left and right movement of
the rudder (see “SET THE CONTROL THROWS”,
page 30).
❏10. Round the leading edge of the fin and the top
and trailing edge of the rudder. Note: Check the
plans to see the location of the dorsal fin and do
not sand the leading edge of the fin in that area.
BUILD THE STABILIZER
❏1. Place the STABILIZER PLAN on your building
board. Cover the plan with Plan Protector.
❏2. From the 3/8" x 3" x 24" balsa sheet, cut a 6"
length, making the stab center. Using more of the
same sheet, make the leading edge joiner.
❏3. Cut 6" from a 3/8" x 1/2" x 30" balsa stick. Pin
it in front of the stab center on the plans.
❏4. Glue the stab center and stab leading edge
joiner to the 1/2" piece pinned to your plans.
❏5. From the 3/8" x 3/8" x 22" basswood stick, cut,
fit and glue the stab spar to the stab center.
❏6. Using two 3/8" x 15/16" x 24" balsa sticks, cut,
fit and glue the leading edge and trailing edge.
❏7. From the leftover 3/8" x 1/2" balsa stick (used to
build the fin and rudder), cut, fit and glue the stab
tips.
❏8. Using a 1/8" x 3/8" x 30" balsa stick, cut, fit
and glue the other four stab ribs in place. After the
glue has dried, remove the stab from your work
surface.
❏9. If you will be installing flying wires, drill two
5/16" holes in the balsa trailing edge in the
locations shown on the plan. Cut two 3/8" long
pieces off the 5/16" dowel. With thin CA, glue the
3/8" pieces in the holes.
BUILD THE ELEVATORS
❏1. Cover the elevator plans with Plan Protector.
❏❏2. From a 3/8" x 15/16" x 24" balsa stick, cut,
fit and pin one elevator leading edge to the plans.

❏❏3. From a 3/8" x 1/2" x 30" balsa stick, cut, fit
and glue the 1/2" elevator ribs and corner gusset to
the leading edge. Note: It is important that the trailing
edge of the ribs align accurately with the plans.
❏❏4. From a 1/8" x 3/8" x 30" balsa stick, cut, fit
and glue the 1/8" elevator ribs to the leading edge.
❏❏5. From leftover 3/8" x 3" balsa (from the stab
center), cut, fit and glue the control horn mount to
the back of the leading edge and also to the
inboard elevator rib.
❏❏6. Push the six T-pins in place as indicated on
the plans, ensuring that they are vertical and firmly
in place.
❏❏7. Wet one of the 1/16" faces of a 1/16" x 3/8"
x 24" balsa stick. Glue the stick to the aft end of the
ribs with the wet side facing out. Pull the stick
around the tip, gluing it to the ends of the leading
edge and tip ribs as you go. Note: Pull the stick just
enough to touch the pins, but do not move them.
❏❏8. One at a time, install the remaining four
1/16" x 3/8" x 24" balsa sticks as you did the first,
using medium CA to glue each successive stick to
the one applied before it and pressing it in position
until the CA dries. Note: Leave some balsa overhang
on both ends to be trimmed off later.
❏❏9. Remove the elevator from the plan.
❏❏10. Trim the laminated sticks off flush with the
elevator ribs.
❏11. Repeat steps 2-10, to build the second
elevator.
❏12. Mark the centerline of the trailing edge of the
stab and of the leading edges of the elevators. Cut
the hinge slots along the centerlines as shown on
the plan.
❏13. Using the fuse plan side view as a reference,
sand the leading edge of the elevator to the “V”
shape shown. Make sure the “V” is large enough to
allow for the specified up and down movement of
theelevators (see“SETTHE CONTROLTHROWS”,
page 30).
❏14. Sand the stab LE and the outside edges of
the elevators to a rounded shape.
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BUILD THE WING
Note: The airfoil used on this plane is semi-
symmetrical. We positioned the embossed labels
on the die-cut 3/32" balsa ribs so that they are
right-side up when the wing is right-side up. This is
the easiest way to reference the top and bottom of
the ribs.
❏1. Glue the two die-cut 1/8" ply W1 doublers to
the two W1B ribs. Glue the two die-cut 1/8" ply W3
doublers to two of the W3 ribs as shown. Note:
These parts mirror each other.
❏2. Trim W1B to match the opening in the doubler
as shown in the photo.
❏3. Select a W2B rib and trim it to match W1B.
❏4. Insert the aluminum wing tube into the paper
wing tube. Fit the two W1Bs, two W2Bs and four
W3s (including the two with the doublers) to the
paper wing tube. Use your rotary tool to enlarge
the holes in the ribs as necessary. When satisfied
with the fit, remove the ribs from the tubes and set
the tubes aside.
❏5. Cut the two 1/8" x 2-1/8" x 14-5/8" birch ply
sheets in half, making four 1/8" x 2-1/8" x 7-5/16"
shear webs.
❏6. Sand a taper on the last two inches of the four
1/8" x 3/8" x 18" basswood spar doublers.
❏7. Glue the four spar doublers to the four 1/4" x
3/8" x 42" basswood spars with the non-tapered
end of the doublers aligned with one end of each
spar. These assemblies are now known as spars.
❏8. Glue the die-cut 1/8" ply forward and rear strut
braces to two of the W5 ribs as shown.
❏❏9. Cover your right wing panel with Plan
Protector. Cross-pin the bottom spar in place on
the plan, aligning the inboard end with the centerline
of the wing, with the spar doubler facing up.
❏❏10. Pin the 1/4" x 3/8" x 42" balsa wing jig to
the plans, with the 1/4" edge against the plans.
Notice how the jig is skewed to provide the required
wing twist (washout).
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❏❏11. Select two of the four W3 ribs you fitted to
the wing tube. Position them in the two W3
locations where the wing tube installs. Glue those
two W3 ribs, one W3 (which was not fitted to the
tube), three W4 and two W6 ribs vertically to the
bottom spar. Glue one W5 with a strut brace and
one W5 without a strut brace in the locations shown.
❏❏12. Using a square to make sure the top spar
aligns with the bottom spar, fit and glue the top
spar in place.
❏❏13. Using the 3/32" x 4" x 24" balsa, cut, fit and
glue the shear webs in place. Note: You will install
the remaining balsa shear webs in the bays that
have pins in them after the wing is turned over.
❏❏14. Glue the 1/8" x 3/8" x 42" basswood
bottom aft spar in place, being careful to keep the
ribs straight over the plans.
❏❏15. Glue the die-cut 1/8" ply W1A in place at
the root of the wing with the spars firmly set in the
notches.
❏❏16. Remove the T-pins at the root of the spar.
Using 6-minute epoxy, fit and glue the ply shear
webs (you cut earlier) in place.
❏❏17. Glue W1B and W2B in place over the
plans.
❏❏18. Glue the top 1/8" x 3/8" x 42" basswood aft
spar in place.
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11
❏❏19. Cut the paper wing tube in half. Insert the
aluminum tube inside the paper tube. Using medium
CA, glue the paper tube to the four ribs and the ply
shear web, aligning the end with the root rib.
Remove the aluminum tube from the paper tube.
❏❏20. Fit and glue the die-cut 1/8" ply tube plug
in the outboard end of the paper tube.
❏❏21. Glue the die-cut 1/8" ply W2A rib in place.
❏❏22. Glue the die-cut 1/8" ply dowel plate (DP)
in place.
❏❏23. Glue the 1/8" x 1" x 42" balsa sub leading
edge to the ribs, centering it vertically on the front
of the ribs.
❏❏24. Using a razor plane and/or sanding bar,
shape the top of the sub leading edge to the
contour of the ribs. Trim the sub leading edge flush
with the wing tip rib and the root rib.
❏❏25. From a 1/4" x 1" x 24" balsa stick, fit and
glue the trailing edge in place in the aileron bay.
Sand the top to the shape of the ribs.
❏❏26. From a 3/8" x 3/4" x 24" balsa stick, cut
and glue the four hinge doublers in place.
SHEET THE WING
❏❏❏❏1. Cut a 1" x 42" strip from a 3/32" x 3" x
42" balsa sheet.
❏❏❏❏2. Edge glue the 1" strip to a 3/32" x 3" x
24" balsa sheet as shown in the photo.
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❏❏❏❏3. Using a square to properly align the
sheeting with the trailing edge of the wing as
shown on the plans, position the sheeting and glue
it in place. DO NOT align with the trailing edge of
the ribs. (See the cross section of the plans.)
❏❏❏❏4. Edge glue the 3/32" x 3" x 42" balsa
sheet to the 3/32" x 2" x 42" balsa sheet (leftover
from the trailing edge sheet), making the leading
edge sheeting. Align the trailing edge with the
center of the spar and glue the sheeting in place.
Note: Be sure to hold the ribs down on the jig and
hold the spar against your flat work surface to
create the correct washout in your wing.
❏❏❏❏5. Use a piece of 3/32" x 3" x 30" balsa
to sheet the center section of the wing.
❏❏6. If this is your second or fourth time through
this section, complete the following steps:
❏❏6a) Cut the 1/4" x 3/8" x 8" basswood stick in
half, making two 4" long aileron servo rails.
Glue one servo rail in the forward square
holes in the W5 ribs.
❏❏6b) Slip the rear 4" servo rail in place. Fit your
servo on the rails, sliding the aft rail forward
until the spacing between the rails is correct
for the servo. Glue the aft rail in place.
❏❏6c) Using leftover center sheeting, sheet over
the servo bay. Cut an opening for the servo.
❏❏7. If this is your first or third time through this
section, glue the die-cut 3/32" balsa rib doubler to
the inboard edge of the tip rib.
❏❏❏❏8. Using 3/32" x 1/4" x 24" balsa stick, cut
and glue cap strips to all of the exposed ribs,
including the trailing edge of the tip rib and its
doubler.
❏❏❏❏9. Trim the sheeting flush with the root rib,
tip rib, sub leading edge and the aileron bay.
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❏❏10. Lift the wing off your work surface. If this is
your second time through this section, go back to
the start of “BUILD THE WING” and build the other
wing half. If this is your fourth time through this
section, go to “FINISH THE WING”.
❏❏11. Flip your wing over, aligning the spar over
the spar on the plans. Notice how you did not have
to move your wing jig -- it still sets the washout for
your wing.
❏❏12. From the 1" x 3" x 7-7/8" balsa block, cut
and fit the filler block between ribs W1 and W2.
Sand the block to the shape of the ribs. When
satisfied with the fit, glue it in place.
❏❏13. Glue two 1/2" x 3/4" x 3/4" basswood strut
blocks into the forward and rear strut braces and to
W5.
❏❏14. Using a piece of leftover 3/32" balsa, fit and
glue a cap onto the bottom of the rear strut block.
❏❏15. Sand the trailing edge sheeting as shown
in the cross section on the plans and in the photo.
❏❏16. Glue the remaining balsa shear webs in
place, as shown on the plans.
❏❏17. Sand the 1/8" sub leading edge and the
1/4" trailing edge to match the contour of the ribs.
❏❏18. Trim the leading edge sheeting flush with
the sub leading edge, W2A, DP, W1A and the tip
rib.
❏❏19. Sand the sheeting flush with the root rib.
❏❏20. Glue the die-cut 3/32" balsa W4 rib doubler
in place at the root end of the aileron bay, then trim
the sheeting flush with the outside of the doubler.
❏❏21. Go back to step one of “SHEET THE
WING” and sheet the bottom of this wing panel.
FINISH THE WING
❏❏1. Glue the 1/2" x 1-3/8" x 42" balsa leading
edge to the front of the wing.
13

❏❏2. Using the plans and the leading edge
gauge as a reference, razor plane and sand the
leading edge to shape.
❏❏3. Hold the 2-1/2" x 2-3/4" x 14-7/8" balsa wing
tip onto the wing tip rib and trace the tip rib onto the
wing tip with a pen. Cut the block on the line you
drew.
❏❏4. Glue the wing tip in place on the tip rib.
Using the plans as a reference, razor plane and
sand the tip to shape.
❏❏5. Cut a 1/2" servo lead hole in the bottom
sheeting near the root rib of the wing.
❏6. Go back to step 9 on page 9 and build the other
wing half.
BUILD THE AILERONS
❏❏1. From two 3/32" x 3" x 42" balsa sheets, cut
two aileron sheets 18-9/16" long. Pin one in place
over the aileron section on the plan.
❏❏2. From a 3/8" x 7/8" x 24" balsa stick, fit and
glue the aileron leading edge to the sheeting.
❏❏3. Position the two end ribs flush with the inboard
and outboard ends of the aileron sheeting. Glue in
place to the sheeting and to the aileron leading edge.
Glue the remaining four aileron ribs in place, using
the location of the main ribs as a guide.
❏❏4. From a 3/8" x 3/4" x 24" balsa stick, fit and
glue the four hinge doublers and the one control
horn support.
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❏❏5. Shape the leading edge, hinge doublers and
the control horn support to the shape of the ribs.
❏❏6. Sand the trailing edge of the sheeting to the
same angle as the top of the ribs.
❏❏7. Glue the other 3/32" x 3" x 18-9/16" balsa
aileron sheet in place. Note: Align the trailing edge
of the sheeting as shown in the photo.
❏❏8. Position and trace around the die-cut 1/8"
ply control horn mount on the bottom of the aileron.
Remove the control horn mount. Cut and remove
the 3/32" sheeting from the area you traced. Glue
the control horn mount in place and sand it flush
with the aileron sheeting.
❏❏9. Sand the leading edge to a V-shape, using
the cross section at W5 on the plans as a guide.
❏10. Repeat steps 1-9 for the other aileron.
BUILD THE FUSELAGE
ASSEMBLE THE FIREWALL
We tested our prototype Super Decathlons with an
O.S.®1.20 4-stroke and with a 25cc US Engine™.
From this point forward when we refer to a glow
installation, we are referring specifically to the
steps we took to install the O.S. 1.20 4-stroke.
Similarly, when we refer to gas installation, we are
referring specifically to the steps we took to install
the US 25. If you are installing a gas or glow
engine other than those listed above, you may
need to modify these steps somewhat to
accommodate your particular engine.
Note: The pieces used to assemble the engine
mount for the gasoline engines are also utilized as
engine mount spacers to position the glow engine
sufficiently forward from the firewall. For clarity, we
will refer to this assembly as “engine mount spacer”
in the glow sections; however, please note that it is
the same piece as the gasoline engine mount.
GLOW ENGINE INSTALLATION
The following 13 steps are for glow installation.
Skip these steps if you are using a gas engine.
❏1. Select the three die-cut 1/8" ply firewall pieces
A, B and C. With the embossed labels toward the
desk top, laminate B onto A then C onto B, all with
6-minute epoxy. This assembly is now known as
the firewall.
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❏2. Turn over the firewall and draw two straight
lines from the outer punch marks. Note: These
lines are used for locating the engine on the firewall.
❏3. Drill four 7/32" holes at the punch marks.
❏4. Laminate the two die-cut 1/8" ply engine
mounts, creating the engine mount spacer.
❏5. Glue the engine mount spacer to the firewall,
centering it on the lines you made on the firewall.
❏6. Drill four 7/32" holes through the engine mount
spacer, using the holes in the firewall as a guide.
❏7. Using a hammer, gently tap the 8-32 blind
nuts into the back of the firewall. Glue the blind
nuts in the firewall with thin CA.
❏8. Loosely mount the Great Planes 60 - 120
engine mount to the engine mount spacer/firewall
with four 8-32 x 1-1/4" socket head cap screws and
#8 washers. Slide the mount halves to the widest
position, then tighten the mount to the firewall.
❏9. Position the engine on the engine mount so
that the spinner backplate is 6-7/8" from the
firewall. Note: Do not confuse the engine mount
spacer with the firewall.
❏10. Mount the engine to the mount with 8-32 x
3/4" socket head cap screws, confirming the 6-7/8"
measurement from the firewall to the spinner
backplate.
❏11. Make a mark on the firewall for the throttle
pushrod. Also make marks for the fuel line holes.
❏12. Remove the engine mount from the firewall.
Drill 1/4" fuel line holes and a 3/16" hole for the
throttle pushrod.
❏13. Go to the “ASSEMBLE THE FUSELAGE”
section.
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GAS ENGINE INSTALLATION
The following steps are for a gas engine installation.
Skip these 10 steps if you are using a glow engine.
❏1. Select the three die-cut 1/8" ply firewall pieces
A, B and C. With the embossed labels toward the
desk top, laminate B onto A then C onto B, all with
6-minute epoxy. This assembly is now known as
the firewall.
❏2. Laminate the two die-cut 1/8" ply engine mounts.
❏3. Drill eight 1/4" holes in the laminated engine
mount at the punch marks. Drill four 9/32" holes in
the firewall at the outermost punch marks as
shown in the photo.
❏4. Using a hammer, gently tap four 1/4-20 blind
nuts into the back of the firewall. Glue in place with
thin CA.
❏5. Using four 1/4-20 x 3/4" bolts, attach the
engine mount to the engine. Note: Make sure the
embossed letters are facing the engine when the
engine is bolted to the engine mount.
❏6. Using four 1/4-20 x 1" bolts and washers,
attach the engine mount (with engine pre- installed)
to the firewall. Note: Tighten the bolts just enough
so that the bolts going into the back of the engine
imprint the firewall.
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❏7. Remove the engine and mount from the
firewall. Using your rotary tool, make clearance
holes in the firewall for the engine mounting bolts
and washers.
❏8. Re-attach the engine and mount to the
firewall.
❏9. Make a mark on the engine mount for the throttle
pushrod. Also make marks for the fuel line holes.
❏10. Remove the engine mount from the firewall
and the engine mount from the engine. Drill 1/4"
holes for the fuel lines and a 3/16" hole for the
throttle pushrod.
BUILD THE BULKHEADS
AND THE FUSELAGE SIDES
❏1. Place the FUSELAGE PLAN on your workbench
and cover the bulkheads with Plan Protector.
Note: For clarity, our photos show the fuse
components off of the plan, but you should build
over the plans.
❏2. Using 1/4" x 1/2" x 30" and 1/4" x 1/4" x 30"
balsa sticks, build the bulkheads 4, 5 and 6. Note:
Use the ends of two different 1/4" x 1/4" x 30"
sticks for the cross-trussing. Save the leftover long
sections of 1/4" x 1/4" stick for the fuse sides.
❏3. Notch the outer framework of bulkhead 4 to
allow clearance for the side windows, using the
plans and the plastic windows as a guide.
❏4. Glue the die-cut 1/8" ply cabin side to the die-
cut 1/8" ply forward fuse side. Repeat this step to
make the other fuse side.
❏5. After covering the fuse plan with Plan
Protector, pin one fuse side in place on the plans.
This is now your right fuse side. Lightly write the
word “right” on the fuse side for easy reference.
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❏6. Glue the die-cut 1/8" balsa top longeron and
die-cut 1/8" balsa bottom longeron to the fuse sides.
❏7. Glue the die-cut 1/8" ply rear fuse side to the
top and bottom longerons.
❏8. Remove the pins from the fuse side and cover
the fuse side with Plan Protector.
❏9. Align the second fuse side over the first and
pin it in place. Glue the longerons and the rear fuse
side in place, making the other fuse side assembly.
These assemblies are now known as fuse sides.
Note: It is very important that the fuse sides be the
same. Take your time aligning these pieces so that
the second fuse side matches the first.
❏10. Lift the left fuse side off the right side and lay
it down mirrored to the right fuse side. Write “left”
on the inside for clarity. Remove both fuse sides
from your work surface. Sand the glue joints
smooth on both sides of each fuse side.
❏11.Glue the die-cut 1/8" ply wing saddle doubler
and the two die-cut 1/8" balsa longeron doublers to
the inside of both fuse sides. Note: Make sure you
built a left and a right fuse side.
❏12. From the two leftover 1/4" x 1/4" balsa sticks
(from making the bulkheads) and two 1/4" x 1/4" x
30" balsa sticks, fit and glue the side stringers in
place.
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ASSEMBLE THE FUSELAGE
❏1. Pin the die-cut 1/8" ply fuse bottom in place
on the top view plans. Note: Make sure the slot in
the front of the fuse bottom matches the plan. This
slot helps set the right thrust.
❏2. Fit the fuse sides, bulkhead 3A and bulkhead
4 in place. Use a square to check that the fuse sides
are perpendicular to your work surface at 3A. Glue
3A to the fuse sides and fuse bottom. Note: The
top of bulkhead 3A has a slight taper towards the
inside, so there should be a slight gap between
your square and the fuse side at the top.
❏3. Glue bulkhead 4 to the sides and bottom,
again making sure the fuse sides are perpendicular
to your work bench.
❏4. Epoxy the firewall in place, again using your
squareto makesurethe fusesides are perpendicular
to your work surface.
❏5. Glue the fuse bottom to the fuse sides.
❏6. Unpin the fuse bottom from your work surface.
❏7. Laminate the two die-cut 1/8" ply tail gear mounts.
❏8. Fit bulkhead 7, the tail gear mounts, the aft
fuse bottom and the stab base to the fuse. Using
your square, check that the fuse sides are
perpendicular to your work surface and glue
bulkhead 7 to the fuse sides.
❏9. Glue the aft fuse bottom to the fuse sides.
❏10. Epoxy the tail gear mounts and the stab
base to the fuse sides.
❏11. Laminate the two die-cut 1/8" ply servo mounts.
❏12. Using the plans to determine positioning and
the servo tray to gain the proper spacing, fit and
glue bulkheads 5 and 6. Note: The bulkheads
extend past the fuse top and bottom at this stage.
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