摘要 |
<p>A ground proximity warning system is disclosed which can recognize when an aircraft is on a final approach to an airport without utilizing a landing flap signal input. Airports (16) together with the surrounding terrain topography are modeled by a simple geometric shape, such as, an inverted truncated cone (4), and stored on-board the aircraft. The system uses navigational data (12, 14) to determine the distance of the aircraft from the geometric model. Once the aircraft is determined to be within the area defined by the geometric model, the system provides an enabling envelope (46) indicative that the aircraft is on a final approach for enabling various ground proximity warning systems. Also disclosed is a system for altering the enabling envelope (46) as a function of the aircraft's alignment with particular runway (50).</p> |