Bending-moment distributions were measured on a model helicopter rotor blade under hovering and simulated forward-flight conditions. The hinged-blade configuration was tested up to an advance ratio u of 0.50, whereas the fixed-at-root configuration was investigated-up to and including u = 0.90.nCurves of maximum-bending-moment distribution are presented for all test conditions. Harmonic bending moments have been found as a result of a harmonic analysis of the data for u = 0.22 and u = 0.47. Theoretical calculations have been carried out at advance ratios of 0.22 and 0.47for the hinged- and fixed-at-root conditions, respectively, and comparisons are made between experimental and theoretical results. Agreement between the results is reasonable in view of the assumptions made in the theory and the experimental errors involved.
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