RE: Goldberg Ultimate 10-300 build
Hi John....................My Blue Hawk Ultimate 10-300 by Carl Goldberg I bought as an ARF. The ARF instructions in regard to determine the Center of Gravity , measure back on the fuselage 2-3/8" from the leading edge of the bottom wing. The C.G. range for this aircraft is 1-7/8" to 2-7/8". It is recommended that you balance this model upside down. Add weight if necessary to achieve the proper balance. Correct balance slight nose down (or level). Mine came with a 16 ozs. fuel tank.
It is important that you seal both wings, elevators and rudder hinge lines. The reason I'm saying this because on my maiden flight I experienced flutter, stripped two 9202 Futaba servos even though my hinge lines were as close as they can get. After sealing the hinge lines everything was just fine.
Recommended setting control surface travels:
Aileron: 10 degs. Gentle Aerobatic 12 degs
Elevator: 12 degs. Gentle Aerobatic 14 degs
Rudder: 15 degs. Gentle Aerobatic 23 degs.
Start with gentle throws this bi-plane especially if this is your first bi-plane.
Mine is equipped with a Saito 1.20 4/s take-offs are just wonderful, add a bit of right rudder input, wait until there is plenty of airspeed and gently rotate, but requires a bit of elevator from go time otherwise it tends to nose (about 1/8 -1/4 up elevator). Requires power during landings, can't cut the power off or it will just drop like a brick. Approach the runway at high idle and go to low idle about one foot above the ground flaring to a three point landing as you gently touch down> Hope this might be of help to you
Charles.