Sensor/Actuator Failure Detection in the VISTA F-16 by Multiple Model Adaptive Estimation

Multiple model adaptive estimation (MMAE) is applied to the Variable Inflight Stability Test Aircraft (VISTA) F-16 flight control system at a low dynamic pressure flight condition (0.4M at 20000 ft). Single actuator and sensor failures are first, followed by dual actuator and sensor failures. The system is evaluated for complete or "hard" failures, patial or "soft" failures, and combinations of hard and soft actuator and sensor failures. Residual monitoring is discussed for single and dual failure scenarios. Performance is enhanced by the application of a modified Bayesian form of MMAE, scalar residual monitoring to reduce ambiguities, automatic dithering where advantageous, and purposeful commands.