This newly declassified video footage from the head-up-display of a U.S. Air Force Arizona Air National Guard F-16 records the dramatic moment when its unconscious pilot is saved from certain death by the aircraft’s Automatic Ground Collision Avoidance System (Auto GCAS).

“Two Recover! Two Recover!”

That’s lead telling his wingman to pull up. It’s a scary situation and something you don’t ever want to hear over the radio. Unfortunately, dash 2 has G-Loc’d and is headed straight for the ground.

The good news: Auto GCAS has kicked in and helped save a life.

Auto GCAS is designed to prevent CFIT (controlled flight into terrain) mishaps by executing an automatic recovery maneuver when terrain impact is imminent. The system predicts those conditions by means of a continuous comparison between a trajectory prediction and a terrain profile that is generated from onboard terrain elevation data.

At the instant the predicted trajectory touches the terrain profile, the automatic recovery is executed by the Auto GCAS autopilot. The automatic recovery consists of an abrupt roll-to-upright and a nominal 5-G pull until terrain clearance is assured.

In the above video, the recovery happened exactly as programmed by Auto GCAS.

“I started to roll and started to pull and I’m following (the instructor pilot) with my eyes,” Ocho (callsign only, name withheld) said. “The next thing I remember is just waking up and hearing ‘recover.’ It happened so fast. Usually, (when experienced at pulling Gs), most people get tunnel vision that gradually comes in. That’s what I always get, but that day I didn’t get anything.”

One of the most dangerous positions for G-loc is to be in a high G turn with your head turned to side looking for the other aircraft. The ability to perform the hook maneuver is limited and the velocity of blood flow to the brain is reduced.