Radar altimeter augmented receiver autonomous integrity monitoring in aircraft

A non-transitory computer-readable storage medium storing computer program instructions executable by a processor to perform operations of an aircraft, the instructions when executed by the processor cause the processor to perform steps comprising:

• receiving, by the aircraft, from each of a plurality of satellites, satellite range measurements;
• receiving, by the aircraft, from one or more global navigation satellite system (GNSS) augmentation systems, one or more corrections to the satellite range measurements and error bounds on the one or more corrections;
• generating, by the aircraft, satellite-position data based on the satellite range measurements, the one or more corrections to the satellite range measurements, and the error bounds on the one or more corrections;
• applying, by the aircraft, each satellite-based position data to a set of parallel tightly-coupled filters to produce a corrected position solution and integrity data;
• applying, by the aircraft, the corrected position solution and the integrity data to a receiver autonomous integrity monitoring system, to produce a protection level for the corrected position solution;
• retrieving historical data of the GNSS augmentation systems;
• comparing actual past errors from the historical data and the corresponding error bounds;
• deriving updated error bounds of the one or more corrections based on ratios between the actual past errors and the corresponding error bounds;
• adjusting the protection level for the corrected position solution using the updated error bounds;
• and
• performing, by the aircraft, an aircraft operation including one of aircraft approach and landing or take off and departure using the corrected position solution and the adjusted protection level.