Glossary

Pilatus PC-12 aircraft

Enhanced Ground Proximity Warning System (EGPWS)

The EGPWS (enhanced ground proximity warning system) was created to alert the pilot captain if a collision with the ground or obstacle is imminent. The Federal Aviation Administration (FAA) defines the EGPWS as a type of terrain awareness warning system.

The Development of the EGPWS

During the 1960s, aircraft accidents involving collisions into terrain were prevalent. These accidents were responsible for the deaths of many people. In an effort to reduce the likelihood of future similar events, a study was conducted to determine the cause.

By the mid-1970s, studies completed indicated that these accidents could have been avoided if a warning system had been used. At this time, the FAA mandated that all turbojet and large turbine aircraft must install a GPWS system.

By March of 2000, the FAA declared that all US registered aircraft with six or more passengers must be equipped with an EQPWS.

Saving Lives one EGPWS at a Time

When the need for an EGPWS first arose, there were approximately 3.5 fatal ground collisions per year. Since the requirement for all large aircraft to install an EGPWS was made in the mid 70s, that number dwindled down to nearly 0 accidents per year.

Today, if such an accident were to occur, most investigations that take place discover that either the pilot captain disabled the EGPWS warning sounds or the EGPWS failed. However, these cases are very rare.