Originally Posted by
speedracerntrixie
Al, we would seem to have different definitions, The way I see it, holding a very slight amount of rudder to hold ground track is not a turn. I fail to see that if the airplane's ground track is strait regardless of the control input how it can be considered a turn. I suppose you would consider a knife edge pass a turn, after all the wings are banked and rudder is applied right?
In knife edge you are opposing the very real force of gravity being applied to the side of your aircraft. Holding rudder in this case effectively gives your fuselage an "angle of attack" to the airflow and this, plus a component of engine thrust balances the force of gravity.
In wings level flight, there is no such force acting sideways on the aircraft as it is flying within the moving air. Its a different scenario, there is no such thing as horizontal gravity. Let me ask a hypothetical question, how would you fly knife edge in a zero g environment? (Ie flying an RC aircraft inside a space craft) Would you need to hold rudder? and what would happen if you did?