Bresnik AeroBresnik Aero
Multi-Engine

Critical Engine & P-Factor

On a twin with both propellers turning clockwise, losing the left engine is worse than losing the right. Slow down to raise the angle of attack and watch the thrust lines shift — the arms stop matching.

Top-down · airflow from topCG axisarm

Thrust-line shift is exaggerated for clarity.

Side · descending blade — bigger biteRELATIVE WINDAoA
Right engine rotationCounter-rotating: descending blade on the left → no critical engine
Rudder needed for each failure
Lose left engine
(right engine working)
Lose right engine
(left engine working)
The critical engine