Emergency Flight Planning for a Generalized Transport Aircraft with Left Wing Damage

Abstract

Flight management systems are highly capable in nominal conditions but are unable to manage most emergency situations, particularly when the performance envelope is degraded due to damage or component failures. Emerging adaptive control and system identification technologies can maintain stable flight given reduced performance, but the pilot must assume the responsibility of guiding the disabled aircraft to a safe landing. With a highly restricted envelope, the family of feasible trajectories may be so unintuitive that a pilot may not be capable of identifying a safe landing flight plan given current high-level automation aids. This paper presents an adaptive flight planner to build landing trajectories for disabled aircraft. A case study is investigated in which a Generalized Transport Model aircraft must land following the loss of a significant fraction of its left wing. Trimmed (non-accelerating) flight conditions define the post-damage flight envelope. Nearby landing runways are prioritized and segmented trajectories to the top-priority sites are defined by trim state and transition sequences. An LQRbased PID controller enables the damaged GTM aircraft to correctly track trajectory commands over trimmed flight and transition segments. A suite of initial conditions are presented to evaluate flight planner performance.