Performance Analysis of a Utility Helicopter with Standard and Advanced Rotors

Abstract : Flight test measurements of the performance of the UH-60 Black Hawk helicopter with both standard and advanced rotors are compared with calculations obtained using the comprehensive helicopter analysis CAMRAD II. In general, the calculated power coefficient shows good agreement with the flight test data. However, the accuracy of the calculation degrades at high gross weight for all of the configurations. The analysis shows fair to good correlation for collective and longitudinal cyclic angles and pitch attitude, and poor to fair correlation for the lateral trim quantities "lateral cyclic angle and roll attitude". The increased solidity of the wide chord blade appears to be a dominant factor in the performance improvement at high gross weight by reducing blade loading and thus delaying stall.