Since the inception of critical digital fly-by-wire systems the commercial and military aerospace industries have struggled with the issue of how to implement auxiliary flight control in the advent of computer and/or command transmission system faults or failures. One potential cause of these problems is the external electromagnetic environment (EME). An electrically isolated auxiliary flight control mode based on power-by-light technology could provide a cost effective, electromagnetic interference (EMI) resistant alternative to the electrical and mechanical backup systems in use today. This paper addresses the benefits and issues associated with power-by-light flight control and discusses the status of ongoing work to bring it to reality.
John R. Todd,
"Power-by-light flight control: an EMI-immune backup", Proc. SPIE 1589, Specialty Fiber Optic Systems for Mobile Platforms, (1 December 1991); doi: 10.1117/12.50985; https://doi.org/10.1117/12.50985