INTEGRATED SYSTEM IDENTIFICATION METHODOLOGY FOR HELICOPTER FLIGHT DYNAMICS

Hopes for reliable identification tools that can be used routinely to support the interpretation of flight test data will only be realised for helicopters if considerably more specialist effort is devoted to the area. The relatively small number of helicopter parameter and system identification studies carried out over the last 15 years has highlighted a range of special problems and the need for an integrated analysis procedure. This Paper continues and builds on this theme, describing the required processes in a systematic methodology. Results are presented, drawn from simulation and flight test data, that illustrate the various stages and highlight some of the problems that can be expected. Stability variations with flight path angle for a Puma helicopter are used in one of the examples to indicate how reduced order models can sometimes provide an adequate description of vehicle dynamics.