Abstract: A system for safely landing an aircraft including a low range radio altimeter, a barometric altimeter, and an autothrottle control. The low range radio altimeter calculates a first height of the aircraft above ground-level, the barometric altimeter calculates a second height of the aircraft above ground-level, and the autothrottle control determines if the first height and the second height do not correlate. If the first and second heights are determined to lack correlation, then automatic thrust-control of the aircraft is stopped. In some embodiments, the second height is partially calculated by accessing a ground elevation database to obtain an elevation of the ground above sea level and determining a difference between the elevation of the ground above sea level and an elevation of the aircraft above sea level.