Can a human survive that? Another article said 9 gs.
9Gs vs 21Gs - either can be fatal or survived - it depends upon DURATION! If they did encounter 21G, it must have been VERY MOMENTARY and even then I tend to doubt the figure. A 150lb (guessing) astronaut in a form-fitted suit would only need to have a single crease to be badly hurt at a load of 3,000+ pounds! The same thing at 9Gs would be very uncomfortable.
I wondered the same thing.