Experimental investigation of transition of a model helicopter rotor from hovering to vertical autorotation

S. E. Slaymaker, Robert R. Lynn, Robin B. Gray
naca-tn-2648
Mar 1952


An experimental investigation has been carried out to study the variation of average induced flow around a model helicopter during transition from a hovering condition to steady autorotative vertical descent. Test data were obtained from simulated power failures under many different conditions. Results are summarized for variations in disk loading, blade angles, and rate of pitch change.

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