[MP-Ryan]

I don't think your brain would suffer permanent damage from hypoxia over that duration.

There are a number of factors that determine the precise amount of time the brain can survive without oxygen before permanent damage occurs, but - generally speaking - most people can handle about 4 minutes without breathing with minor or no brain damage resulting following the loss of consciousness.

If there is also rapid cooling - like due to cold water immersion - people can be revived without damage after much longer periods of time.  In young children, there are cases where they have been submerged in cold water without breathing for hours and have been successfully revived.

TL;DR - a very short-term high-G exposure isn't going to kill any healthy individuals due to lack of oxygen alone.

[Dragon]

High-G exposure doesn't generally kill because of lack of oxygen. Hemorrhaging is what happens during extreme Gs, especially negative ones, while during positive ones, it's usually... well, actually, I dunno. Probably the plane crashing because you blacked out (or got blinded, this is a known side effect of extreme G exposure). I don't think high Gs are a common cause of death, even rockets don't generally exceed 20G. Heck, unless aborting, they rarely get even that. Unmanned Soyuz launches make 5 at most, other rockets probably keep around that value, too (too high TWR is inefficient). You can get around 10G in the Hornet or older F-16s, and that's it. Perhaps also some Russian fighters. I know that even the new F-16s won't let you go above 9, ditto for Raptor (IIRC). In general, in most cases dealing with high Gs (long falls and explosions), you've got bigger problems, such as burns and blunt force trauma.

Really, 10G for 1 minute would kill only if it was applied downward. Human body has a notoriously low tolerance for that. And even then, it'd kill by a hemorrhaging, not hypoxia.

[Mika]

I think you are missing one thing here: 10 G onset rate in this case is high. I.e. you don't get a gradual increment of G forces, but almost instantaneous spike from 1 to 10. There is very little time to prepare the body for that, and I suspect that even trained fighter pilots would have trouble with this. It's sort of sad I didn't get to ride the centrifuge myself when I applied to Air Force, but I did get to feel 5Gs momentarily for some seconds in a glider plane 15 years ago. It was hard to lift hands up in the cockpit, but not because they felt heavy, but because they felt more like you had been sleeping over them for some time. It was weird, I always thought things would feel heavier there but it wasn't exactly like that. I don't know whether it would be the same when going around 9Gs and then doing the controlled breathing and summoning all muscle force there is.

I'm not a physician, but the fact that there is much less oxygen carrying medium during a 10 G pull in the brain is also a major factor. But yes, I think the survival rate would be higher than stated, unless all participants are in a frail condition.

On the other hand, this roller coaster would need to ease up the G only a little bit (say a sequence like 5, 7, 8, 9, 7, 6, 4 G loops), and it would really be a cool G tolerance test system for the general population.

[Lorric]

but I did get to feel 5Gs momentarily for some seconds in a glider plane 15 years ago. It was hard to lift hands up in the cockpit, but not because they felt heavy, but because they felt more like you had been sleeping over them for some time. It was weird, I always thought things would feel heavier there but it wasn't exactly like that.

Ah yes, I thought it would be heavy too, but it's because the blood is being taken away, isn't it. And like if you wake up and immediately try to do something, you're all weak and feeble because the circulation isn't going properly.