I have a similar setup on my smallish pusher ...
Originally posted by simingx
I installed a Mega 16/15/5 with a Master Airscrew 7x4 (gas) prop on my Wattage F-22, gave it a launch... and round it went, rolling RIGHT INTO the ground 2 meters in front of me! No amount of right aileron could save it
It has a broken stabilator now... I wonder if the torque produced was too much for it to handle?
The motor is turning the prop at about 12,500 RPM.
A few less rpm. Same prop - in fact I've used an 8x3.8 as well. 24" WS, 20.6 ounce AUW. Same pusher config. Same stabilator control - no ailerons. No right/down thrust. Approximately 17 ounces static thrust. Never a hint of torque problems during launch. And I don't heave it nearly as hard as my TwinJet.
A maneuver I enjoy watching (more than flying) is to do a slow circuit at eye level & at high AoA and then punch it for a steep, slow climbout. Again, never experienced any appreciable torque reaction with this application of full throttle.
I dunno if this helps or not. But I plan to use EXACTLY the same motor/prop combo as you in the next iteration of my '27, and nothing I had read or experienced to THIS point was suggesting that I would be making a mistake.
I'm always ready to learn, though! If others think this really is a torque problem, I may need to rethink things.