Improved Rotor Smoothing for the U.S. Army CH-47D

Rotor smoothing for U.S. Army rotorcraft must provide both a time efficient and cost effective means for reducing once-per-revolution vibrations. Through anecdotal experience, rotor smoothing systems have proven to be relatively efficient for both UH-60 and AH-64 rotorcraft; however, these same systems have not been as efficient for the CH-47. Improving the rotor smoothing coefficients for the CH-47 will reduce both the time and cost needed to bring the rotorcraft to an appropriate performance level. This paper outlines the effort for improving the rotor smoothing process for the CH-47.