ASSESSING THE NAVIGATION DATA INPUT TO AIRCRAFT FLIGHT MANAGEMENT-SYSTEMS

This paper gives details of the failure rates and the failure modes ex perienced with sps GPS receivers certificated for aviation use to the TSO-C129 specification. These failure rates are significant compared t o those from other modern avionics and the rates are comparable to tha t currently experienced from un-scheduled failures in the GPS signals- in-space. To achieve certification, Flight Management System (FMS) des ign should consider the way in which the satellite navigation receiver s fail. The paper also gives details concerning the 2-D errors that ha ve been experienced with these receivers, and indicates further work t hat needs to be done with C 129a receivers.