P factor

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P factor

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As the tail of aircraft is down, the axis of rotation is inclined. The down-going blade produces greater thrust as it is at higher angle of attack than the up-going blade. This causes asymmetric loading and aircraft making the aircraft tending to yaw.
One of the “left-turning tendencies” of aircraft with a propeller, in which the loading of a propeller disc produces more thrust on one side than the other. If the nose of the aircraft points up relative to the oncoming wind, the downward-moving blade creates greater thrust than the upward-going blade, as the former is at a higher angle of attack than the latter. Assuming that the engine is turning clock-wise as viewed from the rear (as is the case in the majority of single-engine propeller aircraft), the aircraft will tend to turn left. Also known as asymmetric propeller loading.
References in periodicals archive ?
It is easier to win over the people's hearts by bringing in the P-factor in an election discourse.
The goodness of calibration and prediction uncertainty is decided on the basis of the nearness of the p-factor to 100% and the r-factor to 1.
The three forms of the P-factor are noted here in the aggregate.
Returning to the P-factor, introduced in the security calculus above, rules of citizenship and of access are at an interface of the migration-security linkages.
Tracking the loads to capabilities ratio yields a rough rule of thumb about state performance and the potentials for adjusting to the migration elements of the P-factor.
Traffic capacity: The number of circuits required for the stated offered traffic at a given P-factor is prescribed in standard graphic or tabular format depending on the traffic-handling formula selected--that is, Erlang B, lost calls cleared; Poisson formula, lost calls held; or a particular queuing procedure.
Pilots may intentionally create yaw forces to counteract roll from engine torque when the aircraft is moving slowly through the air; counteract the yaw from propeller-generated p-factor when flying with a high angle of attack; slip the aircraft to intentionally create drag; and align the aircraft with the runway when slipping to counteract crosswind drift.
The rudder's primary function is to cancel the many yaw effects associated with flying: adverse yaw arising from aileron inputs; gyroscopic effects arising from elevator inputs; torque, P-factor, and slipstream arising from the use of power; yaw arising from airplane rigging.