So I'm not sure what you are asking. 

P-Factor is an aerodynamic effect that causes propellor-driven planes to yaw 
when they are flown at high power and low speed (takeoff and climbout, for 
example.) At low speeds, the plane flies at a substantial angle of attack, and 
so 
the airflow is not parallel to the plane's axis. Relative to the plane, the 
airflow is directed several degrees upwards. Now the prop axis is normally 
parallel to the plane's axis. As the prop rotates, on one side the blades are 
travelling upwards and on the other side they are travelling downwards. (On 
most 
planes, the prop turns clockwise, as seen from behind, so the left side goes up 
and the right side goes down.) 

The upwards angle of the airflow causes the downward (right) side of the prop 
to have a greater airspeed and angle of attack than the upward (left) side. 
So the downward (right) side of the prop generates more thrust. Pull harder on 
the right side of the plane than on the left and the plane will yaw to the 
left. 

This is one of the reasons why most real prop planes need a certain amount of 
right rudder to keep them straight during takeoff and climbout. 

The other factor that requires right rudder on takeoff (in planes with 
clockwise props) is spiral propwash. The sideways component of the spiral 
propwash 
strikes the vertical stabilizer from the left (in conventional single engine 
configurations), also causing a yaw to the left. In general, the spiral 
propwash 
effect is a lot stronger than P-factor. 

You also need right aileron to keep the plane straight to counteract the 
rotational torque from the engine(s).


Chris Theroux
Gilbert AZ

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