Horizon Hobby HANGAR 9 Aermacchi MB-339 User manual

Aermacchi MB-339
Instruction Manual
Bedienungsanleitung
Manuel d’utilisation
Manuale di Istruzioni
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HAN3390

2EN
NOTICE
All instructions, warranties and other collateral documents are subject to change at the sole discretion of Horizon
Hobby, LLC. For up-to-date product literature, visit horizonhobby.com or towerhobbies.com and click on the support
or resources tab for this product.
Age Recommendation: Not For Children Under 14 Years. This Is Not A Toy.
SAFETY WARNINGS AND PRECAUTIONS
Read and follow all instructions and safety precautions before use. Improper use can result in fire, serious injury and
damage to property.
Components
Use only with compatible components. Should any compatibility questions exist, please refer to the product
instructions, component instructions or contact the appropriate Horizon Hobby office.
Flight
Fly only in open areas to ensure safety. It is recommended flying be done at radio control flying fields. Consult local
ordinances before choosing a flying location.
Batteries
Always follow the manufacturer’s instructions when using and disposing of any batteries. Mishandling of Li-Po
batteries can result in fire causing serious injury and damage.
Turbine Safety
Follow any turbine safety procedures as outlined in the manual for your particular turbine. Additional details can be
found at the AMA website. (https://www.modelaircraft.org/system/files/documents/510-A.pdf)
Small Parts
This kit includes small parts and should not be left unattended near children as choking and serious injury could result.
MEANING OF SPECIAL LANGUAGE
The following terms are used throughout the product literature to indicate various levels of potential harm when
operating this product:
WARNING: Procedures, which if not properly followed, create the probability of property damage, collateral damage,
and serious injury OR create a high probability of superficial injury.
CAUTION: Procedures, which if not properly followed, create the probability of physical property damage AND a
possibility of serious injury.
NOTICE: Procedures, which if not properly followed, create a possibility of physical property damage AND a little or
no possibility of injury.
WARNING: Read the ENTIRE instruction manual to become familiar with the features of the product before
operating. Failure to operate the product correctly can result in damage to the product, personal property and
cause serious injury.
This is a sophisticated hobby product. It must be operated with caution and common sense and requires some basic
mechanical ability. Failure to operate this Product in a safe and responsible manner could result in injury or damage
to the product or other property. This product is not intended for use by children without direct adult supervision. Do
not attempt disassembly, use with incompatible components or augment product in any way without the approval
of Horizon Hobby, LLC. This manual contains instructions for safety, operation and maintenance. It is essential to
read and follow all the instructions and warnings in the manual, prior to assembly, setup or use, in order to operate
correctly and avoid damage or serious injury.
SAFE OPERATING RECOMMENDATIONS
• Inspect your model before every flight to ensure it is airworthy.
• Be aware of any other radio frequency user who may present an interference problem.
• Always be courteous and respectful of other users in your selected flight area.
• Choose an area clear of obstacles and large enough to safely accomodate your flying activity.
• Make sure this area is clear of friends and spectators prior to launching your aircraft.
• Be aware of other activities in the vicinity of your flight path that could cause potential conflict.
• Carefully plan your flight path prior to launch.
• Abide by any and all established AMA National Model Aircraft Safety Code.
BEFORE STARTING ASSEMBLY
• Remove parts from bag.
• Inspect fuselage, wing panels, rudder and stabilizer for damage.
• If you find damaged or missing parts, contact your place of purchase.
• Charge transmitter and receiver batteries.
• Center trims and sticks on your transmitter.
• For a computer radio, create a model memory for this particular model.
• Bind your transmitter and receiver, using your radio system’s instructions.
NOTICE: Rebind the radio system once all control throws are set. This will keep the servos from moving to their
endpoints until the transmitter and receiver connect. It will also guarantee the servo reversal settings are saved in the
radio system.
IMPORTANT FEDERAL AVIATION ADMINISTRATION (FAA) INFORMATION
Use the QR code below to learn more about the Recreational UAS Safety Test (TRUST), as
was introduced by the 2018 FAA Reauthorization Bill. This free test is required by the FAA for
all recreational flyers in the United States. The completed certificate must be presented upon
request by any FAA or law enforcement official.
If your model aircraft weighs more than .55lbs or 250 grams, you are required by the FAA
to register as a recreational flyer and apply your registration number to the outside of your
aircraft. To learn more about registering with the FAA, use the QR code below.

3EN
Aermacchi MB-339
Item # Description
HAN339001 Fuselage
HAN339002 Wing Set
HAN339003 Fin and Rudder
HAN339004 Stab and Elev Set
HAN339005 Retract Set
HAN339006 Retract Controller
HAN339007 Canopy Hatch
HAN339008 Canopy
HAN339009 Joiner Tube Set
HAN339010 Air Intakes (2)
HAN339011 Tip Tanks (2)
HAN339012 Tailpipe
HAN339013 Fuel Tank
HAN339014 Hardware Set
HAN339015 Retract Motor
HAN339016 Nose Wheel (65mm)
HAN339017 Main Wheel (65mm) with Brake (1)
HAN339018 Main Retracts / Struts (2)
HAN339019 Nose Retract with Strut
HAN339020 Fuselage Hatch; Upper
HAN339021 Fuselage Hatch; Lower
REPLACEMENT PARTS
TABLE OF CONTENTS
Notice......................................................................................................................................................................2
Meaning of Special Language..................................................................................................................................2
Safety Warnings and Precautions.............................................................................................................................2
Safe Operating Recommendations...........................................................................................................................2
Before Starting Assembly.........................................................................................................................................2
Important Federal Aviation Administration (FAA) Information.....................................................................................2
Replacement Parts...................................................................................................................................................3
Required for Completion ..........................................................................................................................................3
Required Adhesives .................................................................................................................................................4
Tools Required.........................................................................................................................................................4
Removing Wrinkles ..................................................................................................................................................4
Building Precautions................................................................................................................................................4
Transportation and Storage......................................................................................................................................4
Checking Blind Nuts.................................................................................................................................................4
Replacement Covering.............................................................................................................................................4
Flap Control Horn Installation ...................................................................................................................................5
Aileron Control Horn.................................................................................................................................................5
Flap Hinging ............................................................................................................................................................7
Aileron Hinging ........................................................................................................................................................8
Elevator Hinging.......................................................................................................................................................8
Rudder Hinging........................................................................................................................................................8
Aileron Servo Installation .........................................................................................................................................8
Flap Servo Installation............................................................................................................................................10
Rudder Servo Installation.......................................................................................................................................12
Elevator Servo Installation......................................................................................................................................12
Main Retract Installation ........................................................................................................................................12
Nose Gear Retract Installation................................................................................................................................13
Battery, Receiver and Retract Module Installation...................................................................................................14
Fuel Tank Assembly ...............................................................................................................................................14
Turbine Installation ................................................................................................................................................16
Fin Installation .......................................................................................................................................................17
Stabilizer Installation..............................................................................................................................................17
Joining the Fuselage..............................................................................................................................................18
Wing Installation ....................................................................................................................................................18
Intake Installation ..................................................................................................................................................19
Scale Accessories..................................................................................................................................................19
Center of Gravity....................................................................................................................................................20
Control Throws ......................................................................................................................................................20
Mixing ...................................................................................................................................................................21
Preflight Checklist..................................................................................................................................................21
Daily Flight Checks ................................................................................................................................................21
Limited Warranty ...................................................................................................................................................21
Warranty and Service Contact Information .............................................................................................................22
Instructions for Disposal of WEEE by Users in the European Union..........................................................................22
Academy of Model Aeronautics National Model Aircraft Safety Code.......................................................................23
Building Notes .......................................................................................................................................................23
REQUIRED FOR COMPLETION
# Required Item # Description
1 DUB674 Super Strength Std Servo Arms: JR
2 SPMA3002 Heavy-Duty Servo Extension 9-inch
9 SPMA3004 Heavy-Duty Servo Extension 18-inch
1 SPMAR14400T AR14400T 14 Channel PowerSafe Telemetry Receiver
4 SPMSA5080 A5080 MT/HS Mini Digital HV Servo (elevator, rudder and nose steering)
4 SPMSA6320 A6320 H-T/H-S Brushless HV Servo (ailerons and flaps)
3 SPMX20002SRX 2000mAh 2S 7.4V Smart LiPo Receiver Battery IC3
160-85N Turbine
1Air Trap

4EN
TOOLS REQUIRED
Description
Balancing stand
Drill and tap set, metric
Drill bit set, Imperial or Metric
Epoxy brushes
Felt-tipped pen
Hemostats
Hex wrench set, Imperial and Metric
Hobby knife with #11 blade
Hook and loop straps
Hook and loop tape
Isopropyl alcohol
Low-tack tape
Mixing sticks
Needle nose pliers
Nut driver set, Imperial and Metric
Paper towels
Pencil
Petroleum jelly
Phillips screwdriver: #1, #2
Pin vise
Ruler
Sandpaper
Scissors
Side cutters
Square
Tap handle
Tie wraps
Toothpicks
Wire stripper
REQUIRED ADHESIVES
Description
15-minute epoxy
30-minute epoxy
Canopy Glue
Thin CA
Medium CA
Threadlock, low and high strength
REMOVING WRINKLES
The covering of your model may develop wrinkles during shipping and will require the use of a heat gun (HAN100)
and covering glove (HAN150) or covering iron with a sealing iron sock (HAN141) to remove them. Use caution while
working around areas where the colors overlap to prevent separating the colors. Avoid using too much heat, which
could separate the colors. Placing a cool damp cloth on adjacent colors will also help in preventing the separation of
the colors while removing wrinkles.
BUILDING PRECAUTIONS
Prepare the work surface prior to beginning the build. The surface should be soft and free of any sharp objects. We
recommend resting the airframe parts on a soft towel or pit mat to prevent scratching or denting the surface of the
aircraft.
TRANSPORTATION AND STORAGE
Use the three-view drawing on page 90 to determine how much room will be required to transport and store your
model. We also recommend the use of wing and stabilizer bags to help protect these surfaces during transport and
storage. The control horns and linkages can cause damage to other surfaces even when placed in storage bags.
Always transport and store the wings and stabilizer so the linkages do not contact other panels to prevent damage.
CHECKING BLIND NUTS
When building the aircraft, you will be required to thread machine screws into blind nuts. We recommend pre-threading
the screws to make sure the blind nuts are clear of any debris. If the screws do not thread in easily, clear the threads
using the appropriate tap and tap handle.
REPLACEMENT COVERING
Your model is covered with UltraCote®film in the following colors. If repairs are required, order these coverings to
make those repairs.
HANU870 White
HANU877 Orange
HANU873 Deep Blue

5EN
Aermacchi MB-339
7. Secure the flap control horn to the flap using two M2 x 14
self-tapping screws and a #1 Phillips screwdriver. Note the
angle of the flap control horn in relationship to the flap as it is
biased toward the top of the flap.
6. Place 2–3 drops of thin CA in each hole. Allow the CA to fully
cure before proceeding.
AILERON CONTROL HORN
8. Remove the aileron and aileron hinges from the wing.
ÎThe hinges are not glued to the wing or aileron.
9. Lightly rub a finger over the bottom of the aileron to locate
the mounting slots for the aileron control horn. Use a hobby
knife and #11 blade to remove the covering for the aileron
control horns.
10. Lightly sand the area of the aileron control horns where they
fit into the aileron. (The aileron control horns are the longest
horns included in the kit.)
FLAP CONTROL HORN INSTALLATION
1. Remove the flap and flap hinges from the wing panel.
ÎThe hinges are not glued to the wing or flap.
2. Use a hobby knife and covering iron to seal the covering
against the flap in the location for the flap control horn.
3. Position the flap control horn on the flat area of the flap. Slide
the flap control horn on the flap area toward the bottom of the
flap and toard the wing tip. Mark the location of the flap horn
mounting screws using a felt-tipped pen.
4. Place the horn aside. Use a 1/16-inch (1.5mm) drill bit to drill
the two holes for the flap control horn mounting screws.
5. Use a #1 Phillips screwdriver to thread an M2 x 14 self-
tapping screw into each hole. Remove the screws before
proceeding.

6EN
12. Test fit the aileron control horn. They should fit completely
into the slot as shown. If they don’t fit, use a file to open up
the slot. Do not force the horn in with undue pressure.
11. Use a paper towel and isopropyl alcohol to remove any oils
or debris from the control horn. Prepare all the aileron control
horns.
13. Snap the aluminum ball into the plastic ball end.
ÎApply a drop of light machine oil to the ball to
allow it to move freely inthe plastic ball end.
14. Slide an M3 x 15 button head machine screw into the ball.
It may be necessary to use a small round file to remove any
burrs from inside the aluminum ball. Prepare two ball ends.
15. Slide an M3 washer on the M3 x 15 button head machine
screw. Pass the screws into one of the control horns, then
slide the ball end on the screw.
16. Slide the remaining control horn on the M3 x 15 button head
machine screw. Secure the assembly using an M3 washer
and an M3 locknut.
17. Slide the control horn base on the bottom of the control horn
assembly.
18. Fit the assembly into the slots in the aileron.
19. Place low-tack tape around the control horn base. This will
help keep excess epoxy off the aileron.
20. Remove the assembly and mix 1/2 ounce (15ml) of 30-minute
epoxy. Apply epoxy in the control horn slots.

7EN
Aermacchi MB-339
21. Apply epoxy to all the surfaces of the control horns that will
contact the exposed wood of the aileron.
22. Fit the assembly into the aileron. Use a paper towel and
isopropyl alcohol to remove any excess epoxy. Allow the
epoxy to cure, then remove the tape.
FLAP HINGING
23. Check the hinges to make sure they operate freely. Adjust the
tension of the screw if any hinges do not move freely. Apply
a small amount of petroleum jelly to the hinge flex points to
help prevent adhesive from entering the hinge.
24. Check the fit of the flap to the wing using the hinges. The
flap will align with the wing root. The hinge gap will be equal
along the length of the flap.
ÎDo not apply any adhesives until instructed to do so.
25. Check the operation of the flap to make sure there is
clearance for the flap control horn. Use a rotary tool and
sanding drum if necessary to lightly shape the opening in the
wing for the control horn if necessary.
26. Remove the flap and hinges. Inject adhesive into each of the
hinge pockets of the flap.
ÎDeluxe Materials Aero Tech Epoxy (DLMAD64) was
used in the construction of the Aermacchi MB-339.
27. Inject adhesive into each of the hinge pockets of the wing.
28. Apply a small amount of adhesive to each hinge where it will
enter the flap and wing.
29. Place the hinges in the flap, then join the flap to the wing.
Check the alignment at the wing root, and that the gap
between the wing and flap is equal the entire length of the
flap. The flap will also align with the bottom of the wing.
ÎTrial fitting the aileron at this stage enables an
equal gap between the flap and the aileron.
30. Use a paper towel and isopropyl alcohol to remove any
excess adhesive. Use low-tack tape to hold the flap in
position until the adhesive fully cures.

8EN
AILERON HINGING
31. Hinge the ailerons using the same technique outlined for the
flap hinges. Make sure the aileron is aligned with the flap.
32. Make sure hinge gap is consistent along the entire length of
the aileron. Use low-tack tape to hold the aileron in position
until the adhesive has fully cured.
ÎTrial fitting the tip tank at this stage allows for the
installation of the aileron and verification the aileron
will not come in contact with the tip tank..
ELEVATOR HINGING
33. Separate the elevator from the stabilizer. Set the hinges aside.
34. Install the control horn for the elevator using the techniques
used for the aileron control horn.
35. Use the same technique as the flap hinges to secure the
elevator hinges. Make sure to remove any excess adhesive
from the hinges using a paper towel and isopropyl alcohol.
Use low-tack tape to hold the elevator in position until the
adhesive has fully cured.
RUDDER HINGING
36. Separate the rudder from the fin. Set the hinges aside.
38. When installing the rudder hinges, note that the bottom hinge
has been shortened to fit into the fin.
37. Install the control horn for the rudder using the techniques
used for the aileron control horn.
39. Use the same technique as the flap hinges to secure the
rudder hinges. Make sure to remove any excess adhesive
from the hinges using a paper towel and isopropyl alcohol.
Use low-tack tape to hold the rudder in position until the
adhesive has fully cured.
AILERON SERVO INSTALLATION
40. Remove the covering for the servo arm in the aileron servo
cover using a hobby knife and #11 blade. Make sure the hole
in the cover is aligned with the aileron control horn before
proceeding.

9EN
Aermacchi MB-339
41. Place the aileron servo on the cover and use a felt-tipped
pen to mark the locations for the mounting screws. The servo
output will face forward.
42. Remove the servo and use a pin vise with a 1/16-inch
(1.5mm) drill bit to drill the four servo mounting screws.
43. Thread a servo mounting screw into each hole, then remove
the screws.
5/8 inch
(16mm)
46. When connecting the clevis to the servo arm, use the hole
that is 5/8 inch (16mm) from the center of the servo arm.
47. Secure a 12-inch (300mm) servo extension to the servo lead
using a Servo Connector Clip (SPMA3054).
49. Remove the cover for the flap servo. Use the string to pull the
extension to the opening for the flap servo.
50. Use a toothpick or hobby knife with a #11 blade to puncture
the aileron servo cover for the mounting screws.
48. Tie the string inside the wing to the end of the extension.
44. Apply 2–3 drops of thin CA in each hole to harden the
surrounding wood. Allow the CA to fully cure before
proceeding.
45. Mount the servo using the screws provided with the servo.
Center the servo and attach the servo arm perpendicular to
the servo centerline. Remove any arms that will interfere with
the operation of the servo.

10EN
51. Place the aileron servo cover in position and drill through the
mounting locations and into the wing using a pin vise and
1/16-inch (1.5mm) drill bit.
52. Use a #1 Phillips screwdriver to thread an M2 x 8 self-tapping
screw into each of the holes. Remove the screws before
proceeding.
ÎDo not apply too much force when installing these
screws, as it may damage the wooden servo
hatch frame, or even the wing structure.
53. Apply 2–3 drops of thin CA in each hole to harden the
surrounding wood. Allow the CA to fully cure before
proceeding.
55. Slide a silicone retainer on the metal clevis. Thread the clevis
on the 70mm threaded rod (on the end with the nut) until the
end of the threaded rod is visible between the forks of the
clevis.
54. Secure the aileron servo cover using a #1 Phillips screwdriver
and four M2 x 8 self-tapping screws.
56. Remove the ball from the aileron control horn. Assemble the
linkage so the overall length is 33/4inches (95mm).
57. Attach the ball end to the control horn, then the clevis to the
servo arm. With the radio system on and the aileron servo
centered, adjust the linkage to center the aileron. Once
adjusted, slide the silicone retainer over the forks of the
clevis.
FLAP SERVO INSTALLATION
ÎBefore starting the flap servo installation, set the flap throw
in the transmitter to 0 in both the up and down positions.
58. Snap the aluminum ball into the plastic ball end.
ÎApply a drop of light machine oil to the ball to
allow it to move freely inthe plastic ball end.
59. Slide an M3 x 15 button head machine screw into the ball. It
may be necessary to use a small round file to remove the any
burrs from inside the aluminum ball. Prepare four ball ends.
60. Remove any tape from the wing and flap. Assemble the flap
linkage using two prepared ball ends and an 80mm threaded
rod. Thread the ball ends equally on the threaded rod until the
overall length is approximately 41/4inches (108mm). 41/4inches (108mm)
33/4inches (95mm)

11 EN
Aermacchi MB-339
5/8 inch
(16mm)
61. Attach the ball end the servo arm using an M3 x 15 machine
screw, M3 washer and M3 locknut. Tighten the hardware
using a 2mm hex wrench and 5.5mm nut driver. Make sure
not to overtighten the hardware.
ÎThe washers must be installed as shown to prevent the ball
from popping out of the ball end under extreme loads.
ÎWhen connecting the clevis to the servo arm, use the hole
that is 5/8 inch (16mm) from the center of the servo arm.
62. Insert the linkage, servo arm first, into the wing at the control
horn. Secure the ball link to the flap control horn using an M3
x 15 machine screw and 2mm hex wrench.
64. Guide the servo lead for the flap and aileron through the wing
to the wing root.
65. Center the servo using the radio system. Place the servo arm
on the servo so it is one spline toward the trailing edge of the
wing.
66. Adjust the linkage for the mid flap position of 1 inch (25mm).
Secure the servo arm to the servo using the hardware
included with the servo.
67. Set the throw on the transmitter to the up flap position. Adjust
the values at the transmitter to align the flap to the wing
trailing edge.
68. Set the throw on the transmitter to achieve the throw of
23/4inch (70mm).
63. Install the flap servo with the output forward.

12EN
69. Attach the servo cover to the wing using four M2 x 8mm self-
tapping screws.
RUDDER SERVO INSTALLATION
70. Mount the rudder servo following the instructions in the
aileron servo installation. The output of the rudder servo will
face forward.
71. Secure the rudder servo in the fin following the instructions in
the aileron servo installation section.
72. Assemble the rudder servo linkage following the instructions
in the flap servo installation. Use a 35mm threaded rod and
adjusting the linkage to an overall length of 65mm. Adjust the
length of the linkage as necessary to center the rudder with
the radio system on.
ÎWhen connecting the clevis to the servo arm, use the hole
that is 13/16 inch (20mm) from the center of the servo arm.
ELEVATOR SERVO INSTALLATION
73. Use a hobby knife and #11 blade to remove the covering for
the elevator servo arm.
74. Mount the elevator servo in the stabilizer with the servo
output facing forward.
75. Assemble the elevator servo linkage following the instructions
in the aileron servo installation. Use a 40mm threaded rod
and adjusting the linkage to an overall length of 65mm. Adjust
the length of the linkage as necessary to center the elevator
with he radio system on.
ÎWhen connecting the clevis to the servo arm, use the hole
that is 13/16 inch (20mm) from the center of the servo arm.
MAIN RETRACT INSTALLATION
76. Assemble an adapter to power the retract module. Use the
connector supplied with the retract module and a connector
compatible to the battery chosen to power the module.
ÎMake sure to double check the polarity, as reverse
polarity will damage the retract unit beyond repair.
77. Use a hobby knife or sandpaper to sand a slight taper on each
of the plugs on the adapter (included with the retract module)
that will connect to the receiver to the retract module.

13 EN
Aermacchi MB-339
78. Remove the covering from the retract well on the bottom
of the wing using a hobby knife with a #11 blade. Use a
covering iron to seal the covering around the opening.
79. Route the brake lead and control lead from the retract into
the wing.
80. Retrieve the leads from the same location as the flap and
aileron leads. Make sure to label the leads so they can be
identified when assembling the model for flight.
81. Prepare the retract mounting screws by sliding a 4mm lock
washer, then a 4mm washer on the M4 x 20 socket head cap
screws. Prepare all four mounting four screws.
82. Secure the retract in the wing using the four screws prepared
in the previous step and a 3mm hex wrench.
ÎUse threadlock on the screws to prevent
them from vibrating loose.
ÎIt may be necessary to use thin spacers under the
retract frame to make sure there is no torsional stress
when tightened into position. Torsional stress can
cause intermittent operation of the retract unit.
83. Check the operation of the retract using the retract module.
A test button is located on the module, or the module can be
connected to the receiver to check both the retract operation
and the operation of the brake.
NOSE GEAR RETRACT INSTALLATION
84. Remove the canopy from the forward fuselage. Set the
canopy aside in a safe location.
85. Mount the steering servo in the retract servo opening using
four M3 x 12 button head screws. Apply a drop of threadlock
on each screw, then tighten the screws using a 2mm hex
wrench.
ÎSome servos may require the orientation to be
reversed to avoid contacting the retract unit. To
do so may require a different length pushrod.
86. Assemble the steering linkage and attach it to the servo arm
using an M3 x 15 button head screw, M3 washer and M3 lock
nut. Use a 2mm hex wrench and 5.5mm nut driver.
87. Snap the ball on the steering arm of the retract. Center the
steering servo and adjust the length of the linkage to center
the nose gear.
ÎMake sure to adjust the servo travel so equal
defection is achieved in each direction. Also make
sure the servo is not over traveling as this may
damage the ball attached to the nose leg.

14EN
88. Fit the retract into the forward fuselage. Make sure all the
leads are inside the fuselage and not between the retract
frame and fuselage.
89. Secure the retract using four 4mm lock washers, four 4mm
washers and four M4 x 20 socket head cap screws. Tighten
the screws using a 3mm hex wrench.
ÎIt may be necessary to use spacers under the retract
frame to make sure there is no torsional stress
when tightened into position. Torsional stress can
cause intermittent operation of the retract unit.
BATTERY, RECEIVER AND
RETRACT MODULE INSTALLATION
90. Mount the batteries for the receiver and retract module in the
front of the forward fuselage using hook and loop tape and
hook and loop straps.
91. The retract module can be mounted behind the aft edge of
the nose section. Make sure access to the connecting bolts
are not blocked. Use a switch between the retract battery and
retract module so the retract system can be switched on or
off.
ÎConnect the leads for the main gear retracts and
brakes, as well as the connections to the receiver.
92. Mount the receiver in the fuselage following the instructions
provided with the receiver.
ÎThe leads between the retract module and
receiver can be connected, as well as the
receiver batteries and nose gear steering.
93. Mount the receiver switch in a convenient location in the
fuselage. One of the remote receivers can be secured in the
forward section of the forward fuselage using hook and loop
tape.
94. Mount a second remote receiver in the fuselage using hook
and loop tape. Make sure the antennas are oriented in
different directions.
FUEL TANK ASSEMBLY
95. Locate the rubber stopper, aluminum backplate and
aluminum front plate.
96. Slide a long tube and a short tube through the rubber stopper.
(The center hole is for the screw that secures the assembly in
the tank.) Fit the aluminum backplate on the tubes from the
unflanged end of the stopper. The aluminum front plate slides
on the tubes from the flanged end of the stopper.
97. Use a tubing bender to bend the longer (vent) tube upwards.

15 EN
Aermacchi MB-339
98. Check the bend in the tubing to make sure it does not touch
the top of the tank.
100. Cut a piece of fuel tubing and slide it on the clunk line for the
fuel tank. Fit the clunk and measure the length shown. Adjust
the length of the tubing to achieve the measurement.
101. Use a wire tie to secure the fuel line to the brass fuel line.
102. Use a wire tie to secure the fuel line to the clunk.
99. Use a soldering iron and solder to create an area on each of
the tubes (both outside, and the unbent tube inside the tank)
so the fuel tubing can be secured to the tubes.
103. Fit the stopper in the tank and check that the clunk can move
freely in the tank. Adjust if necessary. Secure the stopper
using the M3 x 25 socket head cap screw. Tighten the screw
using a 2.5mm hex wrench.
ÎDo not overtighten the screw and damage the fuel tank.
104. Remove the hatch from the bottom of the rear fuselage and
set it aside in a safe location.
105. Remove the hatch from the top of the rear fuselage and set it
aside in a safe location.
106. Mount the fuel tank tray in the fuselage from the bottom
using the four knurled screws.
107. Pass the three tie wraps around the fuel tank tray so the fuel
tank can be secured to the fuel tank tray.
101/2inches (267mm)

16EN
108. Slide the fuel tank into the fuselage. Use a small amount of
silicone adhesive between the tray and tank to keep it from
sliding on the tray during flight.
113. Slide the exhaust tube into the rear fuselage from the front of
the fuselage.
114. Align the end of the exhaust tube so it extends 1/4 to 1/2 inch
(6mm to 13mm) beyond the fuselage former at the rear.
ÎIt maybe necessary to slide a thin steel ruler (or
similar) between the exhaust tube and opening in
the fuselage to aid the tailpipe fitting through the
end fuselage former. This is designed to be a snug
fit to retain the tailpipe without any screws.
115. Space the exhaust tube equally between the sides of the
fuselage. Secure the tube using four M3 x 12 self-tapping
screws.
116. Position the turbine in the fuselage. The turbine exhaust cone
will be approximately 1/2 inch (13mm) from the exhaust tube.
ÎThe exhaust tube is the round metal tube
and not the larger orange bell mouth
117. Check there is clearance from objects in front of the intake.
Secure the turbine using the hardware provided with the
turbine.
109. Adjust the position of the tank so the top hatch can be
installed.
110. Secure the tank using the tie wraps. Trim the excess using
side cutters.
111. Remove the covering for the fill and vent fittings using a
hobby knife and #11 blade. Mount the fittings and connect
the lines from the tank.
ÎIt may be necessary to enlarge the holes to install the fittings.
TURBINE INSTALLATION
112. Fit the exhaust guard to the rear of the fuselage so it equally
covers the fuselage. Secure the guard using two M3 x 12
self-tapping screws.
ÎFailure to fit the exhaust guard will result in
heat damage to the wood and covering above
the tailpipe at the rear of the fuselage.

17 EN
Aermacchi MB-339
118. Mount the fuel pump in the fuselage and connect any fuel
lines necessary for the operation of the turbine. Mount the
vent fitting in the bottom of the fuselage and connect the vent
line from the tank. Secure all connections using wire ties.
ÎDo not use tie wraps to secure the fuel lines
as they will deteriorate over time.
FIN INSTALLATION
119. Locate the tube in the rear fuselage in the fin location. Tie the
string to a 48 inch (1200mm) extension.
120. Wrap tape around the connection between the plug and string
to make pulling the extension through the tube easier.
121. Use the string to pull the extension through the tube. Be
careful not to break the string. Connect the lead from the
rudder servo and extension using a commercially available
retainer.
122. Mix 1/2 ounce (15ml) or 30-minute epoxy. Use an epoxy
brush to apply epoxy in the tubes in the fuselage for the fin
and to the surrounding wood.
123. Fit the fin into position. Place a small piece of plastic in the
hinge line and along the bottom of the rudder to prevent
gluing the rudder to the fuselage. Remove any excess epoxy
using a paper towel and isopropyl alcohol.
STABILIZER INSTALLATION
124. Locate the tube in the rear fuselage in the stabilizer location.
Tie the string to two 48 inch (1200mm) extensions. Make
sure the plugs connect to the receiver.
125. Use the string to pull the extensions through the tube. Be
careful not to break the string.
126. Insert the stabilizer tube in the socket in the rear of the
fuselage. Center the tube in the fuselage.
127. Connect the lead from the elevator servo and extension using
a commercially available fastener. Slide the stabilizer on
the tube. Use a 3mm hex wrench to tighten the screw that
secures the stabilizer to the fuselage.
ÎThe screw may require loosening to fit the stabilizer.

18EN
128. Insert the stabilizer screw grommet using a small amount of
silicone adhesive.
JOINING THE FUSELAGE
129. Slide the four fuselage joining tubes into the front half of the
fuselage.
131. Slide the forward fuselage into position on the rear fuselage.
They will fit tightly together.
130. Prepare the five screws that secure the forward fuselage to
the rear fuselage by sliding a tapered washer on an M4 x 20
socket head cap screw.
ÎA small round file may be required to slightly
enlarge the hole in the tapered washer.
132. Secure the fuselage section using the five screws prepared
earlier. Tighten the screws using a 3mm hex wrench.
ÎUse threadlock to keep the screws from vibrating loose.
ÎCheck the screws periodically as the wood formers may
compress over time and result in the screws becoming loose.
133. Mount the remote receiver above the fuel tank using hook
and loop tape. Connect any extensions for the flaps, ailerons,
retracts and brakes and route them back in the fuselage.
134. Place the canopy hatch in position on the fuselage.
WING INSTALLATION
135. Slide the wing tube into the socket in the wing. Do not force
the tube in farther than it will easily slide.
136. Slide the tube into the socket in the fuselage. Connect the
leads for the aileron and flap to the extensions. Guide the
leads for the retract and brake into the wing.
137. Slide the wing tight against the fuselage.

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Aermacchi MB-339
138. Use the two 1/4-20 x 2-inch nylon bolts to secure the wing to
the fuselage.
139. Connect the leads for the retract and brake inside the
fuselage.
INTAKE INSTALLATION
140. Fit the intake to the wing. There will be space of 1/4-inch
(6mm) at the rear corner near the fuselage.
141. Use a pin vise and 1/16-inch (1.5mm) to drill to drill the
locations in the intake into the wing. Remove teh intake and
thread an M2 x 8 self-tapping screw into each hole. Remove
the screws and place a drop ot thin CA in each hole. Once
the CA have fully cured, secure the intake to the wing using
twelve M2 x 8 self-tapping screws.
SCALE ACCESSORIES
142. Prepare the wing tip tank bolts by sliding a 4mm lockwasher
on the M4 x 220 socket head cap screws.
143. Attach the tip tank using the screws and a 3mm hex wrench.
144. Use a hobby knife and #11 blade to remove the covering for
the VOR blade antenna in the fin. Glue the antenna to the fin
using medium CA. Use a square to make sure the antenna are
aligned correctly on both sides of the fin.
ÎThe antenna are purely cosmetic and
do not require installation.
145. Slide a 4mm lock washer and 4mm washer on the M4 x 20
socket head cap screw for the ventral fin attachment. Prepare
all four screws.
146. Use the screws and a 3mm hex wrench to attach the ventral
fins to the bottom of the fuselage.
ÎRemove the ventral fins for transport.

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CONTROL THROWS
1. Turn on the transmitter and receiver of your model. Check the movement of the rudder using the transmitter.
When the stick is moved to the right, the rudder should also move right. Reverse the direction of the servo at the
transmitter if necessary.
2. Check the movement of the elevator with the radio system. Moving the elevator stick toward the bottom of the
transmitter will make the elevator move up.
3. Check the movement of the ailerons with the radio system. Moving the aileron stick to the right will make the
right aileron move up and the left aileron move down.
4. Use a ruler to adjust the throw of the elevator, ailerons and rudder.
Surface Rate Exponential Direction Throw
Aileron
High 20% Up 13/8inch (35mm)
Down 1 inch (25mm)
Low 15% Up 1 inch (25mm)
Down 25/32 inch (20mm)
Elevator
High 20% Up 25/32 inch (20mm)
Down 25/32 inch (20mm)
Low 15% Up 19/32 inch (15mm)
Down 19/32 inch (15mm)
Rudder
High 20% Left 217/32 inch (65mm)
Right 217/32 inch (65mm)
Low 15% Left 19/16 inch (40mm)
Right 19/16 inch (40mm)
Flaps Partial 1 inch (25mm)
Full 23/4inch (70mm)
Flap Throw
The full flap throw creates a lot of drag slowing the model very quickly. Test at a safe altitude.
CENTER OF GRAVITY
An important part of preparing the aircraft for flight is properly balancing the model. The Center of Gravity range
supplied here is a guideline based on testing. Deviation from the measurements we provide is possible and may result
in a model that suits your flying style better. Start with the recommended Center of Gravity, then feel free to experiment
with different balance points. We advise adjusting progressively and cautiously.
1. Assemble the model and ready it for flight. Make sure to connect the leads to the appropriate leads from the
receiver. Make sure the leads are not exposed before tightening any hardware. Your model should be flight-ready
before balancing.
2. The recommended Center of Gravity (CG) location for your model is 41/2inches (114mm) behind the leading edge
of the wing against the fuselage.
3. When balancing your model, make sure it is assembled and ready for flight. Support the plane inverted at the
marks made on the wing with your fingers or a commercially available balancing stand.
ÎThe overall CG range for this model is 41/2–6 inches (114–152mm). We recommend starting
at the measurement listed above, then adjusting to suit your particular flying style.
CAUTION: You must adjust your aircraft’s center of
gravity and balance your model properly before attempting flights.
41/2inches
(114mm)