SAE AIR 4253A

This information report (AIR) provides design information of various contemporary aircraft fly-by-wire flight control actuation systems that may be useful in the design of future actuation systems for similar applications. This AIR provides a description of representative state-of-the-art, fly-by-wire (FBW) actuation systems used in flight control systems of manned aircraft. It presents the basic characteristics, hardware descriptions, redundancy concepts, functional schematics, and discussions of the servo controls, failure monitoring, and fault tolerance. All existing FBW actuation systems are not described herein; however, those most representing the latest designs are included. While this AIR is intended as a reference source of information for future aircraft actuation system designs, the exclusion or omission of any other appropriate actuation system or subsystem should not limit consideration of their use on future aircraft.