TERRAIN ADVISORY SYSTEM

A terrain advisory system utilizes stored data representative of terrain and other obstacles in predetermined geographical areas of interest to provide advisory warnings of the proximity of terrain, obstacles and restricted areas as they are approached. When used in a vehicle such as an aircraft, the system monitors the position, altitude, ground speed, ground track and the vertical speed of the vehicle and provides advisory indications of the position and path of travel of the vehicle with respect to obstacles and terrain. Such advisory indications may take the form of voice warnings describing the nature and position of any obstacles, or a visual display showing the position of the obstacles and terrain with respect to the vehicle.