How do fighter pilots handle blacking out due to high-g maneuvers?

How do fighter pilots handle blacking out due to high-g maneuvers? originally appeared on Quorathe knowledge sharing network where compelling questions are answered by people with unique insights.

Answer by Tim Hibbetts, F/A-18C pilot, on Quora:

Sometimes you wake up, sometimes you don’t. It can take several seconds to regain full function. If the aircraft is not far enough away from the ground when the lone pilot comes around, all his worries are over. It’s likely the same outcome if you start napping in the middle of a fight.

If quickly deprived of oxygen, the brain has about five seconds of useful consciousness. That’s generally enough to let go of the stick if you know what’s coming. But if you have rapid-G onset, which most modern fighters are capable of delivering, you can be unaware you’ve just put the brain’s blood reserves in a back pocket. When this happens, G-force-induced loss of consciousness, or G-LOC, occurs.

If you haven’t yanked on the pull, there are times when you can experience the various stages up to G-LOC and let up on the stick pressure to keep from entering sleepy time. The tunnel vision, loss of color vision, sparkly peripheral vision, and a few others are good indicators that you’re at the edge. That next step, black out, is a fine slice between here and not here.

I actually experienced this in centrifuge training. The techs who were running the trainer called it “A-LOC”–almost loss of consciousness. They said they’d never seen anyone get there and come back. The timing with the end of the ride was perfect. Here is a snippet from my training; it’s the last of five or six 10- to 20-second sessions at high-G. For this one, we have to look at —> Read More