Zero-gravity atmospheric flight by robust nonlinear inverse dynamics

Abstract : Zero gravity flights can be obtained for short periods with common subsonic aircraft. Thus, many valuable experiments and otherwise expensive training can be achieved at low cost. This note considers the design of an autopilot flight control law to realize such a maneuver with a high degree of accuracy. Accurary is impaired by atmospheric turbulence, local aerodynamic perturbations, and thrust fluctuations on one side and by the limited knowledge about the aircraft mechanics that is used in the design of the contro laws on the other side.