A Simulation Environment for Performance Evaluation of Flight Path Reconstruction Methods In Extended Flight Envelope Applications

To assist ongoing efforts towards the development of flight path reconstruction (FPR) methods that address the challenges associated with large amplitude maneuvers and high angle of attack flight, a novel extended-envelope flight test simulator was presented. The flight test simulator featured an aerodynamic model in which coupled longitudinal and lateral aerodynamic characteristics are determined on the basis of the flow separation model due to Fischenberg, and earlier work by Goman and Khrabrov. Simulated measurements were generated using sensor models developed on the basis of experimental evidence according to a representative modeling philosophy. The adopted sensor models describe sources of transient measurement errors anticipated in high angle of attack applications. To illustrate the potential significance of such measurement errors in post-stall flight testing applications, a simulated flight test dataset featuring a straight stall maneuver was presented. Analysis of the simulated measurements revealed that the adopted sensor models resulted in non-Gaussian errors and significant distortions in the measured lift curve. The work concludes with a brief comparison of FPR performance achieved by the conventional maximum a posteriori (MAP) estimator and the recently presented robust MAP estimator when applied to the simulated flight test dataset. The poor FPR performance obtained by the conventional MAP estimator illustrated the inadequacy of conventional FPR methods in flight testing applications involving rapid motions and large angles of attack, while also underscoring the need for effective methods for FPR performance evaluation.