Modeling and analysis tools for aircraft control system evaluations

A systematic approach for successful control system evaluations of future high-performance aircraft is presented. The approach involves the integration of several modeling and analysis techniques into one evaluation methodology. The evaluation methodology has been used successfully to evaluate several production fighter aircraft and rotorcraft flight control systems. The modeling tools discussed include linear model extraction from nonlinear simulations, linear model build-up, and equivalent system model reduction. Efficient techniques for validating and comparing complex linear models are also presented. The stability and handling-qualities-analysis tools used are in the evaluation methodology result in direct comparisons of control-system characteristics with military flying qualities and flight-control-system specifications. Tool and technique descriptions are supplemented by lessons learned from previous flight-control evaluations