Space Shuttle Orbiter entry through landing navigation

The Space Shuttle Orbiter navigation system must be capable of determining its position and velocity throughout a variety of operational regimes. The design and operation of the entry through landing navigation system is described as it operates during a nominal end of mission from the orbital coasting phase throughout atmospheric flight and landing. Design and operation of the Kalman filter is described. Stabilization of the altitude channel prior to acquisition of external measurement data is described. Utilization of the Tactical Air Navigation (TACAN), barometric altimeter, and Microwave Scan Beam Landing System external measurement data is described. A comparison is made between predicted performance and the navigation accuracy observed during flight.