Strat,

The pitch is normal associated with the 75% blade section...and a zero pitch prop will be very close to reaching the zero thrust speed. Further, after your prop reachs an AOA of about 5 or 6 degrees the thrust starts to fall off pretty quickly. Now if you take the Thrust generated at a given speed this will give you the power that is being used to drive the model. (Thrust*Speed=Power).....Lets say that our plane reach zero thrust speed (20fps) and let say that at 10 fps and is generating .5 pound of thrust then the power would be 5 p/fps...lets say it is a .40 the manufater rates the engine at .9 HP which is about 500 pfps. 5/500=eff..... 1% eff. Actually for full size airplane 85% effeciency is the normal number used. If you are using the Manufatures HP rating for most RC engines, I would be suprised if you will find a prop that will even come to 30 percent effeceincy. With the correct dyno HP you might be able to get to 40%. So in general to have a comperable plane compare to there big brothers you will need about 2.5 time the HP/wieght ratio to make up for the difference in prop effecency.

Steve