© 2008 Stevens AeroModel.
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Motor and propeller mounting: Mount the Hacker A20-20L, A30-28S, VSport 280, or E-Flite Park 480 using the radial
mounting hardware included with your motor package. Secure the motor to the firewall using the provided four (4) 4-40 x
3/8” machine screws (thread-locking compound on these screws is highly recommended). Proper down thrust is built into
the firewall. Four 1/16 in. plywood washers are provided in this kit (sheet 20/21) to shim the left side of the motor (as
viewed from the cockpit) to achieve proper right thrust. Place both ply washer under each of the two left side motor mount
arms. Right thrust will vary with your power system selection but we have found that with the recommended Hacker A30-
28S and 10x5 propeller one 1/16 in. shim is typically about right. To reduce right thrust simply remove the shim and
reduce it’s thickness through sanding.
Install your balanced propeller to the motor. Never run a propeller assuming it is in balance without checking it first.
Never run a propeller that is known to be damaged, repaired, or out of balance. Never run a motor with a bent shaft. In-
flight vibration from out of round and out of balance components will cause pre-mature failure of airframe and electrical
components. If you are un-certain how to balance a propeller, seek advice from an experienced hobbyist or your local
hobby retailer.
Mount the wing: Retain wing to fuselage using the provided 1-1/2 in. nylon mounting bolts.
If using the rubber band on wing option. Retain wing to fuselage using four (4) #33 rubber bands two (2) on each side of
the fuselage. Use fresh rubber bands prior to each flying session. DO NOT cross the rubber bands, use bands of greater
size / thickness, or exceed six (6) rubber bands (three per side) as this will prevent the wing from cleanly departing the
fuselage in the event of a crash.
Landing gear assembly: Place wheels on the landing gear assembly and retain by forcing the 1/8” star washer wheel
retainers over the 1/8” axle. Depending on the wheels provided with your kit you may need to ream the hubs to fit the 1/8
in. axle diameter.
Retain landing gear to fuselage using two (2) #33 rubber bands one (1) on each side of the fuselage. Use fresh rubber
bands prior to every flying session. Use the method for landing gear attachment as described previously in this text.
Battery installation and Center of Gravity: Move battery fore and aft within fuselage to adjust the models Center of Gravity
(CG). We suggest locating the CG of the model in the upright position so that the fuselage bottom is level with the horizon
when balancing the airframe by a finger tip positioned on the underside of each wing panel 2-3/4 in. aft of the wing leading
edge. This initial CG is suitable for your first flights, move CG aft cautiously to enhance soaring capabilities.
Lateral model balance: Place a round head pin in the rudder assembly near the bottom of the rudder. With the rudder
aligned parallel to the fuselage and vertical stabilizer support the model inverted with one finger on pin head and the other
finger on the motor shaft. With the model suspended in this fashion your wing tips should balance level with the horizon.
If your model does not balance laterally, add an appropriate amount of weight to the “high” wing tip until model balances.
Hint: I use adhesive graphics like contrasting color bars on the underside of my wing to balance the model and aid
visibility.
Warped structure: Check wing and tail surfaces over carefully looking for signs of twists or warps that will need to be
removed prior to flying. In the unlikely event that you have a warped surface, have a partner heat the covering of the
surface using a heat gun on low heat setting while you gently apply a corrective twist to the structure opposite the warp.
Allow the surface to cool while holding the corrective twist. Release correction and check to see that you were successful.
If need be, repeat process until surfaces are straight and true.
Pre flight check (perform every flight):
o
No visible damage to airframe or covering?
o
Flight pack batteries charged?
o
Transmitter batteries fully charged?
o
Proper model selected on radio? (applies to computer radio)
o
Range check of radio successful?
o
Center of gravity set properly (2-3/4 in. from leading edge of wing)
o
Control rods securely connected?
o
Fresh rubber bands properly installed on wing and landing gear?
o
Control surfaces moving proper directions? (don’t just wiggle them, check for proper direction of travel)
o
Propeller
secure?
o
Clear the propeller and perform run-up. Smooth throttle response with no vibration?
o
Flying site clear?
Upon successful pre-flight announce your departure and commit aviation!
o
Point model into wind smoothly apply power and corrective right rudder.
o
Model should lift off in about 10-15 feet with application of ¾ throttle.
o
Climb out smoothly to safe altitude. Trim model for level flight in both pitch and roll axis.
