Status of Fiberoptics Technology for Propulsion Control Systems

Because of optics' inherent immunity to electromagnetic noise it offers considerable promise in improving the reliability of propulsion control systems. Future engine systems will be electronically controlled with no hydromechanical backup. The electronic computer will have to be isolated from electromagnetic noise by heavy shielding of metallic transmission lines. Fiberoptic data transmission and passive optical sensors can insure more complete isolation of the computer from electromagnetic disturbances and thereby produce a more reliable control system.

This paper discusses work being done by NASA Lewis Research Center in the area of optical sensors and optically controlled actuators for use in airbreathing engine control systems. The environmental conditions in which the aircraft will operate, require the fiberoptic cables and optical connectors to perform reliably at temperatures over the −55°C to 260°C range. The status of fiberoptics technology for operation in this environment is reviewed.