Thread: Fixing Roll
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Old 04-17-2011, 12:40 PM
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bongodriver bongodriver is offline
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Quote:
and there is no prop on the ever popular car anology, when the engine is revved hard causing lurch
no but there is a large 'flywheel' so it's not completely invalid.

for the spitfire it's like this....


torque: prop rotates clockwise, aircraft rotates anti-clockwise, has the smallest effect of all 3.

propwash: causes the aircraft to yaw left with increased power...right rudder required to counter

gyroscopic precession: pitch up causes yaw right, pitch down causes yaw left, this seems to be the strongest effect, if you are trimmed with a pitch up bias the aircraft will want to roll right.

all these forces will change according to power setting and control inputs, only rudder and elevator can be trimmed, therefore there will tend to be a requirement to keep hands on stick to counter all the secondary roll forces induced by yaw, and this is largely felt as a roll right, even a fixed aileron 'tab' will only be effective at a set speed range.
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