Maximum G-Force Tolerance for Human Body: Can We Withstand Hypersonic Speeds?

[Mind Bender]

I'm fascinated by hypersonic aircraft. But what is the fastest velocity the human body can withstand? Mach 6, Mach 8? I look forward to the day when people can circle the globe in a matter of minutes. Will this be possible?

 

[berkeman]

I'm fascinated by hypersonic aircraft. But what is the fastest velocity the human body can withstand? Mach 6, Mach 8? I look forward to the day when people can circle the globe in a matter of minutes. Will this be possible?

Going a constant velocity in a vehicle is not an issue. It is the acceleration that generates forces on the body (F=ma). The right question to ask is how much acceleration can the human body withstand over an extended period.

Trained and fit aircraft fighter pilots can withstand 9 times the acceleration of gravity (one "g" = 9.8m/s^2) for brief periods of time. The Space Shuttle astronauts withstand (withstood) several g's while accelerating to orbit (you can probably find the acceleration profile on NASA's website somewhere). The Space Shuttle launch profile is probably the most applicable to your final question in the post above.

 

[Ryan_m_b]

Trained and fit aircraft fighter pilots can withstand 9 times the acceleration of gravity (one "g" = 9.8m/s^2) for brief periods of time.

If I remember correctly this is true for vertical g-force, for horizontal g-force 2 or 3 times more is survivable.