Performance of an optimized rotor blade at off-design flight conditions

An investigation is made of the aerodynamic performance of a helicopter rotor previously optimized for minimum 4/rev vertical shear and blade weight subject to certain dynamic and structural constraints. The program CAM RAD which was used in designing the optimized blade is used for both dynamic and aerodynamic analysis. The aerodynamic performance of the optimized rotor is analyzed over a wide range of operating conditions and for a larger number of rotor characteristics than those considered in designing the blade. The assessments are made based on the power required by the rotor for a given rotor task, the rotor lifting efficiencies, maximum rotor thrust envelopes and the control margins. Results are presented for the optimized blade and the reference blade, which was used as the baseline for the optimized blade, for two rotor tasks.