Test results of F/A-18 autoland trials for aircraft carrier operations

Raytheon and the US Navy conducted aircraft carrier precision approach trials using the F/A-18 as the test platform. These trials are part of the Navy Joint Precision and Landing System (JPALS) effort to demonstrate Global Positioning System (GPS) technology for aircraft carrier precision approach. The team achieved the historic milestone of the first fully coupled approach and landing to the ground in an F/A-18 using a GPS-based navigation solution. These trials used a Raytheon Navigation and Landing System developed test bed, Rockwell-Collins 24-channel Enhanced Miniature Airborne GPS Receiver (EMAGR), and US Navy aircraft integration. This paper shows data and analysis that measures and/or models accuracy of the test bed and GPS measurements. This is done in two phases. The first phase demonstrates the performance of the existing test bed as performed real-time using ship and airborne platforms. The second phase shows post processed analysis of measurement data and a proposed relative navigation solution. Because the ship environment is unique to the precision landing technology, special considerations must be made to monitor integrity and to model continuity. Considerations include ship flexure, RF interference, ship blockage, pseudorange multipath, carrier phase multipath, and ship dynamics. The test and analysis results show that GPS technology provides the quality needed to perform relative precision approaches in an aircraft carrier environment.