Hey Matt,

I think one of your questions has to do with horizontal versus vertical flight and why we don't see as much effect on torque in horizontal flight? Well, the torque is there all the time, but it's most noticeable when you're slow with lots of throttle. With models, that's hard to do unless you're vertical. If you are flying a full-scale 152 or something like that, you can see the impact of torque big time when you do power-on stalls. The goal here is to bleed off airspeed and get the nose high. You feed in power so you can maintain altitude. It's been a while, but I think you can get the airspeed down to 25 knots or so, depending on temperature and loading. When you are in that position, you have a lot of right rudder to keep things straight. In the model world, you're most likely to experience something similar on takeoff, especially a modestly powered nose-wheel aircraft taking off from a grass runway. If you pull back too soon or too hard, the plane will snap off to the left.

So, the torque is always there, you just feel it most in slow, high-throttle situations. For straight and level flight, we usually trim it out. Problem is that when you slow down or speed up relative to where you trimmed the airplane, you do get some yaw (and other stuff, like roll). Full scale pilots spend a lot of time flying the plane with trim. You set trim to one place for take-off. Trim for climb-out. Trim for cruise, etc.