Automatic propeller synchronization on multi-engine aircraft helps reduce vibration by aligning what?

Automatic propeller synchronization on multi-engine aircraft helps reduce vibration by aligning what?

• A. Phase angles between propellers
• B. Blade pitch angles
• C. Fuel flow rates
• D. Engine oil temperature

Answer: (C)

Synchronizing propellers reduces vibration by aligning the phase angle between the propellers. When two Propellers turn at the same RPM, the cyclic loads from each blade create a repeating vibration pattern. If the blade passages are out of step, those vibrations can interfere and produce noticeable beating. Keeping the phase in sync means the blade passages align in time, so the forces add more smoothly and the overall vibration is reduced. This adjustment specifically targets the relative angular position of the blades, not blade pitch, fuel flow, or oil temperature.

Synchronizing propellers reduces vibration by aligning the phase angle between the propellers. When two Propellers turn at the same RPM, the cyclic loads from each blade create a repeating vibration pattern. If the blade passages are out of step, those vibrations can interfere and produce noticeable beating. Keeping the phase in sync means the blade passages align in time, so the forces add more smoothly and the overall vibration is reduced. This adjustment specifically targets the relative angular position of the blades, not blade pitch, fuel flow, or oil temperature.