Dynamics and Stability of an Autorotating Rotor/Wing Unmanned Aircraft

The development of and results from a dynamic analysis of a hybrid autorotating rotor/wing aircraft are presented. The aircraft is intended for use as an unmanned reconnaissance vehicle to be air launched from the pylon of a base aircraft. The rotor/wing aircraft may be operated as a conventional, fixed-wing airplane or as an autogyro for low-speed surveillance and landing. Analysis presented includes dynamic stability and control features of the autogyro configuration. Generally, the autogyro exhibits dynamic modes characteristic of a conventional aircraft with the exception of an additional, slowly convergent mode associated with the rotor angular velocity degree of freedom. The rotor angular velocity also plays an important role in the unstable autogyro phugoid mode. Control effectiveness in the autorotating configuration is generally good, though it is recommended that the rotor longitudinal cyclic control be assisted by the elevons to enhance control power in pitch.