Ground Proximity Warning

Ground Proximity Warning System (GPWS) and its enhanced version EGPWS (Enhanced GPWS) are safety systems that alert flight crews when the aircraft is in dangerous proximity to terrain, preventing Controlled Flight Into Terrain (CFIT) accidents.

EGPWS modes include:

• Mode 1: Excessive descent rate ("SINK RATE, PULL UP")
• Mode 2: Excessive terrain closure rate ("TERRAIN, PULL UP")
• Mode 3: Altitude loss after takeoff or go-around
• Mode 4: Unsafe terrain clearance with gear/flaps not configured
• Mode 5: Below glideslope deviation ("GLIDESLOPE")
• Mode 6: Altitude callouts (500 ft, 200 ft, minimums)

EGPWS adds a forward-looking terrain database, providing alerts up to 60 seconds before potential terrain impact. Mandatory on all turbine aircraft with 6+ passenger seats.