Outcome-based framework for online model validation and risk awareness

Juan Jurado, Air Force Test Center (USA)
Clark McGehee, Air Force Test Center (USA)

Abstract

Current Flight Test Continuation Criteria (FTCC) rely on comparing differences between expected and observable aircraft states for safety-of-flight decisions. Even state-of-the-art methods, which can make such comparisons using real-time simulations, are based on subjective thresholds derived from organizational practices. Using Wickert’s Risk Awareness framework [1], where system knowledge is the “control parameter opposing drift into a mishap state,” this paper proposes a novel method for real-time modeling and analysis of aircraft data to inform whether the aircraft flown is an acceptable version of the simulated aircraft. In this method, the bounds of acceptability (i.e., the Knowledge Envelope) are derived from flight control robustness ground testing. These bounds are directly traceable to the probability of experiencing an unacceptable outcome, such as departure. The proposed method is mathematically formulated, compared to existing state-of-the-art approaches, and applied to specific scenarios from recent envelope expansion programs in the Air Force Test Center.