This pilot films himself taking off in an F15e Strike Eagle and reaching 4 miles of climb in a matter of seconds. An untrained person would have likely passed out from the g-forces of this takeoff. The human body can withstand a pretty good amount of force, but it can't survive a constant g-force. For instance, a slap on the face could transfer hundreds of g's locally, but the cheek can absorb the pressure. Any sustained g-force of more than a minute above 16 g's can prove fatal, though.