ORIGINAL: jcmccorm
Guys, thank you very much Bill and Carl.
With regards to the propellor washing over the the rudder, then for every propellor turning clockwise (looking from rear), matched with a vertical stabilizer mounted on top, you'd always have to add some left thrust to the engine. A vertical stab mounted on the bottom then (odd, but just an example) would require right thrust.
I don't quite understand the torque effect with respect to rolling the airplane left and causing it to turn left. It seems like the axial torque would definitely change with throttle setting and want to roll the plane but it would take a lift vector component in the "left" direction for the plane to want to turn left (ie banked left) and I imagine we always subconscously correct for this.
Cary
No. When you look forward from the rear of the aircraft, some of the airflow strikes the left-hand side of the vertical fin and rudder, imparting a nose-left force. You want RIGHT thrust to counterract it. If the vertical surface was below the fuselage, it would be struck on the right-hand side, imparting a nose-right force. You'd need LEFT thrust in that case.
The actual torque effect is minimal because of the fact that the wings impart a huge damping force with respect to the actual torque reaction of the engine.
Within the past few months, Peter Garrison of Flying Magazine, did an article on this which analyzed the forces that cause the nose-left tendency of an aircraft, and why some aircraft have an offset built into the verical fin and why you need to add right rudder during takeoff and climb in an aircraft with a clockwise-turning propeller (when viewed from the cockpit.