FLY-BY-WIRE TECHNIQUES

Abstract : Manual flight control systems are described in which the sole means of control between the pilot's station and the control actuator is in the form of electrical signals. No mechanical control links are used in the system. Such a system is defined as a fly-by-wire control system. Because of the growing number and severity of problems in mechanical control systems, particularly in large and high speed aircraft, fly-by-wire systems are evolving out of necessity. Fly-by-wire control is shown to provide many advantages over conventional mechanical flight control systems. Principally, they are reduced weight and volume, improved control performance, reduced design effort and maintenance time, and the feasibility of standardizing flight control systems. System design requirements and tradeoffs are discussed such as the types of components used, control signal format, method of transmitting signals, actuator configurations, degrees of redundancy, failure detection techniques, and artificial feel mechanization. Examples are given of the application of fly-by- wire control to various classes of aircraft. The primary benefits derived depend on the class of aircraft. Control system technology has reached the point where practical fly-by-wire system designs can be realized today. The next logical step in its development is to build and fly a fly-by-wire system to demonstrate its feasibility and after many flight hours to provide in-flight proof of its maturity.