Full Authority Digital Engine Control System For The Chinook Helicopter

When the U.S. Army's special operational force (SOF) of MH-47E Chinook helicopters enters service in late 1991, full authority digital electronic controls (FADEC) will be included as part of the up~maded Textron Lycoming T55-L-714 turboshaft en~mnes. The British Royal Air Force (RAF) will follow suit in 1992, when FADEC will be included in the mid life update of their HC-MK1 Chinook. These applications will be the first introduction of a modern technology electronic control on the Chinook helicopter and will replace a thirty year old conventional hydromechanical control that is presently in service. The design rational, functional performance and qualification requirements of the digital electronic control system are described relative to fulfilling the particular requirements of this tandem rotor helicopter. Also, operational and installation features of the engine control system are discussed, such as reliability, maintainability, diagnostics, history recording, health monitoring, aircraft incorporation and cost-of-ownership, to ensure that the original design philosophy and goals of the program would be satisfied. The recent culmination of very successful engine and flight tests clearly indicated the fulfillment of all operational and performance benefits promised at the initiation of the program,