EVALUATION OF RIDE QUALITY PREDICTION METHODS FOR OPERATIONAL MILITARY HELICOPTERS

A simulator study was conducted to compare and validate various ride quality prediction methods for use in assessing passenger/crew ride comfort within helicopters. Thirty-five military pilots experienced and rated selected combinations of simulated helicopter interior noise and vertical vibration measured during routine flights. Specific objectives included; quantification of crew comfort, comparison of existing and new ride quality metrics, determination of best metric, and identification of possible ride quality criteria approaches. Results of this study indicated that crew comfort results from a complex interaction between vibration and interior noise. Reducing either noise or vibration alone provided little improvement in ride quality. Reductions in both were required. The best metric for predicting crew comfort to the combined noise and vibration environment was the NASA discomfort index. The results were also used to derive tentative comfort criteria that account for the relative effects of both noise and vibration.