Paratrike. Determining the Thrust Vector During Flight. The P Factor

During level flight, the propeller must be perpendicular to the direction of travel. This will compensate for the so-called “P-factor.” In aviation, the P-factor refers to the asymmetric load on the propeller, which causes the trike to yaw to the left at high angles of attack. The P-factor is more pronounced in configurations with higher power or at higher angles of attack, so the phases most prone to the “P-factor” are takeoff runs and climbs.

The P factor o propeller factor This is noticeable when the trike has a «high-nose» configuration (high angle of attack). As a result of this configuration, the propeller has a greater angle of attack during its downward stroke than during its upward stroke. This results in a difference in thrust.

The P-factor is a result of the asymmetric thrust generated by the propeller during its downward phase (propeller turning to the right: greater angle of attack and greater thrust) and upward phase (propeller turning to the left: smaller angle of attack and lesser thrust) in high-nose configurations. The greater thrust exerted by the propeller on the right side results in a left-hand yaw (left-leaning).

The greater the trike's angle of attack (the higher the nose is), the more significant the effect generated by the P factor will be.

• The effect of the P factor manifests itself differently depending on the flight phase:
• During the takeoff, the trike will experience high angles of attack, and therefore the propeller's asymmetric thrust effect will be predominant and must be compensated for with «right brake«As we reduce the angle of attack, its influence will decrease accordingly.".
• During the ascent during a cruiseThe effect will be more or less noticeable depending on the angle of attack at which this climb is performed. Compensating for it will also require the use of «right brake«, trimmer….".

This is important for the propeller to operate smoothly. It is not possible to keep the propeller at a right angle to the airflow in all flight modes, but when the ppgtrike is in horizontal flight mode, this is usually sufficient.