New integrated INS/GPS mechanization flight test results

Summary form only given. Litton Aero Products has recently completed flight testing a prototype of their latest INS/GPS (Global Positioning System/inertial navigation system) system mechanization in which the LTN 2001 GPS PR and DR measurements are sent directly to the LTN-92 INS Kalman filter by means of an ARINC 429 interface. The advantage of this approach is that individual satellite measurements are used independently in the INS Kalman filter. These measurements are therefore uncorrelated, and can be correctly modeled in a single, integrated INS/GPS Kalman filter which optimally combines information from both systems. Yet, the GPS sensor is an independent unit which is not embedded in the INS. For civil aviation, this PRDR mechanization makes possible a delayed, integrity-assured integration algorithm. This mechanization was flight-tested in Litton's Cessna Citation aircraft and also in Boeing's Advanced Avionics Test Bed aircraft.<>