Ground Proximity Warning System

In a with a Ground Proximity Warning System (German: Ground Proximity Warning System ) equipped aircraft are in low altitude below 762 m radio altitude (2500 ft) from different data criteria derived in below which an alarm is triggered in the cockpit.

History

The system was introduced in 1975 and was a response to so-called CFIT (Controlled Flight into Terrain ) accidents in which an otherwise fully functional aircraft was flown ' into the ground '. The GPWS is operating in a range of 9 m to 747 m height above ground (radar height). Five different conditions ( modes, such as modes) result in exceedance of different limits to warnings.

GPWS modes

In all modes except mode 6, warnings are issued acoustically as well as visually:

Information flow GPWS

The GPWS processes signals from the radio altimeter ( height above ground ) from ADIRS (Air Data and Inertial Reference System: pressure measurements and inertial navigation, from the barometric altitude, vertical speed and the speed ), the instrument landing system (ILS, from the filing of the glide), ( extended or not ) from the Flight Management Computer and Guidance Computer, from the chassis of the landing flaps ( position).

An additional signal " stable " from Flight Warning Computer stops all GPWS spending because the response to a stall has priority. In addition, individual mode circuit can be suppressed by an "Inhibit".

Human machine interface

The GPWS alerts are issued as auditory display (sounds and speech), in addition as a visual display ( text message and indicator lamp ) in the field of view of each pilot. Are given exact values ​​( the amount or rate of descent ), the alarms raise awareness and increase situational awareness. The operation is done with buttons in the overhead panel.

Development

Using a terrain database and positioning satellite system for the Enhanced Ground Proximity Warning System was developed.