Power-off flare-up tests of a model helicopter rotor in vertical autorotation

S. E. Slaymaker, Robin B. Gray
Jan 1953

This report presents the results of an experimental investigation into the problem of reducing the descending velocity of a helicopter model in steady vertical autorotation by expending the kinetic energy of the rotor in a collective-pitch flare. Test data were obtained over a wide range of operating conditions from a freely falling model rotor restrained laterally by a guide wire.

An Adobe Acrobat (PDF) file of the entire report: