Multi Engine Commercial Checkride Practice Test

An increase in vibration during flight is typically indicative of potential engine trouble. This can stem from various sources within the aircraft, such as imbalance in the engine, propeller issues, or mechanical failures. When vibrations exceed normal levels, they can signal that something is not functioning as intended, which may require immediate attention from the pilot to ensure safety.

In contrast, a successful flight path would refer to achieving a planned navigation route without issues, which is not directly related to vibrations. Normal operation suggests that everything is functioning within expected parameters, which would not typically include an increase in vibration. Improved aerodynamics usually indicate enhanced performance and efficiency, which is also unrelated to vibrations. Therefore, recognizing increased vibrations as a sign of potential engine trouble allows pilots to take appropriate action to maintain safety.