EASY Question #2:

What equipment prevents an aircraft from impacting the terrain? Which systems help prevent an aircraft from colliding with the ground? What equipment protects a plane from terrain impact?

Answer:

The primary equipment is the Ground Proximity Warning System (GPWS) and its advanced version is the Enhanced Ground Proximity Warning System (EGPWS). These systems use radio altimeters, GPS signals and terrain databases to provide visual and aural alerts when an aircraft is in danger of colliding with the ground. Also, pilots are trained to respond immediately to any “pull up” warning. Together with stabilized approach procedures, this equipment has significantly reduced controlled flight into terrain (CFIT) accidents.