Validation of the Dynamic Response of a Blade-Element UH-60 Simulation Model in Hovering Flight

The dynamic fidelity of an operational blade-element simulation model of the UH-60 helicopter is assessed for the hovering and low-speed flight regimes. Nonparametric frequency-domain identification techniques and time-history comparisons are used to determine the validity of total-vehicle on-axis and coupled responses. A dedicated flight-test program was conducted to provide data used in the analysis. The flight-test techniques and data verification methods employed are briefly described. Frequency-domain methods are applied to the model and to several model components in order to isolate deficiencies and verify refinements and corrections. Model deficiencies are also identified by using side-by-side pilot assessments of a motion-base simulation and of a test aircraft. Model updates are found to significantly improve fidelity in the frequency range that is of interest to handling-qualities research. The applicability of the model to high-bandwidth flight-control research is also discussed.