Critical digital systems: a fly-by-light consideration

Addresses the benefits and issues associated with fly-by-light technology and discusses the status of ongoing work. The rapid increase and evolution of digital electronic aircraft systems has evidenced some new and potentially troublesome failure modes heretofore not encountered with commercial aircraft. One potential cause of some of these faults or failures is the external electromagnetic environment (EME) in which aircraft must operate. In many systems fiber optics could provide cost effective EME protection. Douglas Aircraft has conducted or been directly involved in six flight test programs dealing with the fiber optics aspects of fly-by-light and associated with a number of others. The baseline Douglas Aircraft fly-by-light architecture shown was developed in 1984 from an internal study chartered to design a highly reliable digital flight control system for future transport aircraft. As an adjunct to the fly-by-wire/fly-by-light test integration facility work, Douglas Aircraft is also integrating a fly-by-light cockpit simulator which is discussed