Please un-torque my neurons.... Prop effects et al...

[A Squared]

Well, here's my thoughts on the matter:


First, gyroscopic precession.

There is no gyroscopic precession (acting in yaw) when there is no pitching motion. That's not to say that it doesn't exist; it certainly does when the tail comes up on a high powered taildragger during the takeoff roll. But in a steady state climb in a stable constant pitch attitude, there is no precession going on. So if we're talking about the forces in a constant climb, we can ignore precession.

Next, reactive torque. Sure there is some, and it does act around the longitudinal axis of the plane, but how big is it really?

well lets consider the C-172 engine which develops 150 hp at 2700 rpm. That equated to 291 ft-lbs of torque at full power and rpm. So how much is that in real terms? It's about the same as having a 200 lb passenger sitting in a seat 1.45 ft to one side of the aircraft center line. In other words if the rolling moment from engine torque was unopposed (more on that in a moment) it would be about the same force as the difference between having an adult male in the passenger's seat, and not having one. It's not non-existent, but it's also not very significant.

The thing is, it *isn't* unopposed, which brings us to spiraling slipstream. Personally, I suspect that the propeller slipstream doesn't "spiral" quite as much as it's made out to in the primary flying texts. But, no doubt it does some, and whatever spiraling it does will tend to roll the airplane as it impinges on the wings, fuselage and empennage. But it tends to roll the airplane *opposite* the reactive torque from the engine. So, it tends to reduce the already, "not very large" rolling moment from the engine torque.

So that leaves us with P factor, or asymmetrical propeller disc loading, which in a low airspeed, high power climb, is the predominant force and acts only in Yaw (or very nearly so)

so to summarize:

Precession: Absent in a constant climb

Engine torque: Produces relatively small rolling moment in a typical GA aircraft.

Spiraling slipstream: Serves to counteract rolling moment from engine torque.

P-factor: No significant rolling moment.


Now, I fly single engine GA aircraft (although regrettably not as much as I'd like to) and like the others you've talked to, I'm not aware of having to hold significant aileron input on a climb, but I am aware of the need to hold rudder. No doubt I do, subconsciously, hold a very small amount of aileron.

Now, I don't fly single engine flight simulators, but if the required aileron input in a *real* airplane is well below the consciously discernible level (and it is) , and the required aileron input in the simulator is well above it, (like you say) then it would seem to me that the simulator is not programmed to be an accurate representation of the real thing.

I'm not sure how you'd conclude anything else.