R
Robert Moretti
Last year, I changed from a two-blade fixed prop to a two-blade feathering prop. Generally, I'm glad I did. Engine performance and speed suggest that my new prop is pitched correctly. However, at about 2400 RPM there is a new vibration that disappears at about 3000 RPM. The vibration is best described by thinking of a wave. That is, the vibration increases in intensity, then falls away, then increases, etc. At 2400 RPM, the vibration occurs with a period of about 1.5 seconds. The period shortens with increased speed, until the vibration disappears. I don't know where to start to figure out the cause. Any ideas? Thanks!