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Old 06-09-2016, 08:07 AM
  #25  
E-Challenged
 
Join Date: Sep 2002
Location: Garden Grove, CA
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I am flying a 1/6 scale "stick model" SigJ-3 Cub, six foot span, single piece wing about 5lbs with batteries. . I have a functional side door and window setup to install and change battery packs. Magnets hold door/window closed. I am using two 2200mah 3S lipo packs in parallel for 4400mah 3S and using a Cobra 3515/14 950KV brushless motor, 12x6 APC prop and 45 amp Cobra speed control with built in switch mode BEC rated at 3 amps. Battery packs are in front of the cabin with fronts of packs in line with the instrument panel. The CG on mine is line with the wing's main spar. This arrangement does not require lead nose ballast in my Cub. Removing the wing to replace battery packs is too fiddly for me. I recommend large metal clevises to attach wing struts to lugs on the fuselage, with silicone tubing keepers. Screws and nuts are fiddly. Cubs are not very critical about CG, should hang slightly nose down with finger tips at specified CG point. With my setup I get a safe 9 minutes with some wild aerobatics and cruising flight. Model can fly inverted, loop from level flight, and even do an outside loop. Wings are strong and struts are secure. I fly my Cub with aileron/rudder mix most of the time, can switch it off for cross-controlled maneuvers. Cubs need a lot of rudder throw to bring tail around with the rest of the airplane. Use your rudder ( left stick) to counter tendency of model to swing left during takeoff. Hold some up elevator to keep tail wheel on ground during first 20 feet of takeoff run as speed gathers, release up elevator to let tail rise and keep straight with rudder. Let model lift off when it's ready with little or no up-elevator. Keep climb at a shallow angle to avoid stalling and let model get some altitude before turning. Have a friend adjust elevator and aileron trim for you while you keep flying. Model should fly level at half throttle, climb at full throttle, and descend a 1/4 throttle. For landings try to line up for landing and reduce throttle so model settles down to runway . Don't try to "flair" at first. Land on main wheels and let tail settle as you reduce throttle. When you have a feel for stall characteristics, you can try flairing for 3-point landings. Your main wheels should be pointed straight ahead or slightly" pigeon toed" to minimize ground loop tendencies. Practice take off runs using elevator and rudder to keep straight and cut throttle before liftoff. My Cub wants to overshoot the end of the runway during landings. It's easiest to land into a headwind. Avoid taking off and landing in strong crosswinds. BTW, my Cub has equal up/down aileron throw, doesn't need differential aileron throw. I use dual rates on ailerons and rudder, fly mostly on high rates for aerobatics and cruising. There are a lot of good You Tube how-to videos about flying tail-draggers. Cubs were used as the first training step to flying warbirds during WWII. Hope this helps you enjoy your Cub for many pleasurable flights.

Last edited by E-Challenged; 06-09-2016 at 08:34 AM.