Flew maiden on an old 40 Koas today. Used a new os 46 sf, hi-torq micro servos. Increased elevator throw- was not able to get off ground. After the trim adjustment, the Koas flew great with very little trim. This bird took off in a head wind of about 10-12 knots in about 25 feet. Smooth, tracked well, landed easily. It has a 4 oz. tank. Should get 15-20 minutesw flying time. This engine is a fuel sipper and powerful to boot.