If accelerating at a steady rate over the 20 seconds, the average g force would be 2.28 g.
Erm... you can do that at any decent fairground. What you can't do is have the world outside your window at a standstill then, 20 seconds later, it's doing 1000mph.
I liken it to a deep dive - a very deep dive - it's all very exciting hurtling down the shot-rope but then you get to the wreck and straight away you have to think about how you're going to get back up to where gas is free and you can breathe as much as you want.
I'm only a plumber from Cannock...
"As to reward, my profession is its own reward;" Sherlock Holmes.
'It ain't what they call you, it's what you answer to.' W.C. Fields.
Yes, you will get a similar experience at a fairground, but 2.28 g is the average and initial acceleration could easily be double or triple that, leading to temporary "redout", assuming Rosco is riding feet first with the g forcing blood towards his head.
You make a good point about the sudden change in surroundings though. Humans generally need some time to adjust to moving surroundings and one has to wonder how hard it will be to make the adjustment from 0 to 1000 mph in just 20 seconds, especially if one has vision impairment initially into the bargain...
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