What causes the left turning tendency of an airplane known as P-factor?

The left turning tendency known as P-factor primarily occurs due to the asymmetrical thrust produced by the propeller. When an airplane is in a climb or at a high angle of attack, the descending propeller blade on the right side of the aircraft encounters a higher relative wind, resulting in greater thrust compared to the ascending blade on the left. This differential thrust creates a yawing moment towards the left, causing the aircraft to turn in that direction.

Understanding this phenomenon is crucial for pilots, especially during takeoff and climb, as it influences how the aircraft will respond to control inputs. The manipulation of power settings and maintaining appropriate rudder input are vital actions for counteracting this left-turning tendency.