G-force induced loss of consciousness (abbreviated as G-LOC) is what can happen when gravitational forces effectively drain blood away from the brain. While the condition is best known as a serious issue that fighter pilots and astronauts face, you can experience G-LOC on a really good roller coaster. First your vision goes…you get tunnel vision and/or you “greyout”, where the color in your vision disappears, then your vision as a whole starts to fade out. Kept up too long, and unconciousness will occur. For pilots and astronauts, G-LOC is a danger, and one that must be fully understood by the individual. That means training…both to handle high-g situations, and to determine where nap time will be achieved. Don’t think that doing well in these training situations is easy: a combination of special breathing patterns, concentrated muscular straining and flexing is needed in order to keep the human functioning, and if you aren’t prepared for it ahead of time, you won’t be able to catch up once you enter a high-g situation. I know…I learned the hard way when a flight instructor went a little too hard trying to force a Cessna 172 into an accelerated stall.

The flight officer in this video is preparing to undergo intentional G-LOC training…the goal is for the effects of gravity to take over for the Sandman’s job, leaving this otherwise professional slumped over in the seat, dreaming sweet dreams. During testing, this guy will see up to 8.5 g‘s…for comparison, a Bugatti Veyron at a dead launch will hit 1.55 g and the Space Shuttle averaged about 3 g. How well do you think you’d do in this trainer?