SEVERAL AIRLINES and manufacturers will evaluate AlliedSignal Aerospace's enhanced ground-proximity warning system (EGPWS) during 1996. Development units are to be shipped to British Airways, United Airlines, Bombardier, Cessna, Dassault and Gulfstream.

Where today's GPWS monitors various aircraft instruments to provide an audible warning of proximity to the ground, the EGPWS adds a worldwide digital terrain-database, which is used to provide a visual display - and advanced warning - of threatening terrain.

By "looking ahead" within the database, the system can alert pilots to a potential terrain threat. Integrated with the electronic flight-instrument display, the EGPWS can show terrain ahead of the aircraft, colour-coded to indicate the level of threat posed. The system will generate aural and visual cautions within 60s of impact and warnings within 30s, compared with about 10s for conventional GPWS.

AlliedSignal plans to begin shipping production units in March, pending US Federal Aviation Administration approval of the system. The EGPWS will be basic equipment on the Bombardier Canadair Challenger and Global Express, Gulfstream V and McDonnell Douglas MD-95. The system will be optional on the Cessna Citation X and Dassault Falcon 900EX.

United plans a three-month trial of the EGPWS in 20 Airbus A320s, running from May to July, and will retain the systems if the trial is successful. AlliedSignal is not alone in seeing a sizeable forward-fit and retrofit for the system, which directly replaces GPWS - Collins has teamed with Dassault Electronic to develop a broadly similar ground-collision avoidance system.

Source: Flight International