How does a propeller synchrophasing system allow a pilot to reduce noise and vibration?

How does a propeller synchrophasing system allow a pilot to reduce noise and vibration?

• A. By adjusting the phase angle between the propellers on an aircraft's engines
• B. By adjusting blade pitch automatically
• C. By equalizing engine temperatures
• D. By synchronizing fuel flow across engines

Answer: (A)

When multiple propellers interact, the pressure changes each blade creates can crowd into the same moments, making louder noise and stronger vibration. A propeller synchrophasing system adjusts the relative timing of the blade passages between the propellers, keeping a steady phase difference. By offsetting when each propeller’s blades reach the same point in their cycle, the peaks in air pressure don’t line up, so the overall vibration and noise are smoothed out. This is specifically about the timing of the blades, not about changing blade pitch, engine temperatures, or fuel flow.

When multiple propellers interact, the pressure changes each blade creates can crowd into the same moments, making louder noise and stronger vibration. A propeller synchrophasing system adjusts the relative timing of the blade passages between the propellers, keeping a steady phase difference. By offsetting when each propeller’s blades reach the same point in their cycle, the peaks in air pressure don’t line up, so the overall vibration and noise are smoothed out. This is specifically about the timing of the blades, not about changing blade pitch, engine temperatures, or fuel flow.