Integrity in flight control systems
In connection with advances in technology, mainly in the electronic area, aircraft flight control applications have evolved from simple pilot-relief autopilots to flight-critical and redundant fly-by-wire and active control systems. For flight-critical implementations which required accommodation of inflight failures, additional levels of redundancy were incorporated to provide fail-safe and fail-operative performance. The current status of flight control systems reliability is examined and high-reliability approaches are discussed. Attention is given to the design of ring laser gyros and magnetohydrodynamic rate sensors, redundancy configurations for component failure protection, improvements of hydraulic actuators made on the component level, integrated actuators, problems of software reliability, lightning considerations, and failure detection methods for component and system failures.