Rotor Aeromechanics Results from the Sikorsky Active Flap Demonstration Rotor

A large scale demonstration rotor with integral trailing-edge active control flaps was designed and tested to evaluate technologies that utilize higher harmonic control to improve noise, vibration and aerodynamic performance. The high authority flaps are controlled by embedded high-power-density electro-mechanical actuators. The rotor system was tested on the Sikorsky Main Rotor Whirl Stand and in the National Full Scale Aerodynamics Complex 40x80 ft wind tunnel. This paper summarizes the mechanical and instrumentation systems, but concentrates on describing examples of the aeromechanics results in the areas of rotor aerodynamics, unsteady blade structural loads and pressures, required trim controls, and trailing edge flap forces. Comparisons are made to computational results for rotor performance, and blade response to actuation, and the results of this experiment are generalized and compared to results of other related experiments.