Vibration Analysis and Testing of Bell 429 Helicopter

A multi-layered vibration treatment approach for treating cabin vibrations was used for the development of the Bell 429. The approach consisted of minimizing the 4/rev vibrations entering the airframe from the main rotor, tuning the airframe structure to place dominant modes away from excitation sources, and treating remaining cabin vibrations locally with vibration absorbers. This approach provided an effective vibration treatment solution. A description of the 429 vibration treatment solution, the dynamic analyses and vibration testing performed to support the development of that solution, and flight test data showing the effectiveness of the solution are included.