Somewhat ghoulish SF reference. In Alastair Reynolds' "Absolution Gap" a spacecraft responds to an emergency beacon. The spacecraft has safeguards to prevent it from killing its passengers through excessive G forces, but it happens to be unaware that it has a passenger. The ship reaches distress signal at maximum speed, and when the person rescued opens up the passenger's spacesuit, he finds bloody pulp full of broken bones. What kind of acceleration THAT would take? I estimate about 100 g, before ribs break under their own weight.

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Fiction has to be plausible. Reality is under no such constraint.