Biology
How Sustained G-Forces Affect the Human Body
Quick fact
Under sustained high g-forces, blood is pulled toward the lower body, reducing blood flow to the brain and eyes. This can cause tunnel vision, grey-out, or G-induced loss of consciousness (G-LOC) if the brain's oxygen supply drops too low.
Why this is interesting
Why do fighter pilots sometimes lose vision during high-speed turns, and how do they train to withstand forces that would make most people black out?