On a multiengine airplane, where the propellers rotate in the same direction, why is the loss of power on one engine more critical than the loss of power on the other engine?
The corkscrew pattern of airflow from one propeller is less effective against the airflow from the critical engine.
The torque reaction from operation of the critical engine is more severe around the vertical axis as well as the longitudinal axis.
The asymmetric propeller thrust or P-factor results in the center of thrust from one engine being farther from the airplane centerline than the center of thrust from the other engine.✓ Correct Answer
Explanation
With both propellers turning clockwise (seen from behind), P-factor moves each engine's center of thrust to the right, so the right engine's thrust line is farther from the centerline. Losing the left engine leaves that longer-armed right thrust, creating more yaw, so the left engine is critical (Airplane Flying Handbook Chapter 12).
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