7.2 g acceleration. You could strap a human on there and they'd survive the acceleration phase.
this post was submitted on 05 Jan 2026
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For an untrained person this might well be lethal.
Only 2 seconds of horizontal g? Not unless they weren't securely against the seat and died due to blunt force trauma from being slammed into the seat back.
My cousin would try it, and she would bring me
Well now we need to design the train with all seats facing forward and restraints to keep people in place, and we need to have staff abord to do do a safety check that everyone is seated and strapped in before we can get those 2 seconds of theoretically-survivable acceleration.
Come on. This is cool from an engineering perspective but will never be used on an actual passenger train.
Lol I was certainly not claiming this was practical, just pointing out it wouldn't be lethal in that sense.
It’s completely not practical.
7Gs is, granted, not categorically lethal hut average people will start to pass out around 4Gs if the acceleration is vertical, and 9 is about the upper limit that trained, fit Air Force pilots can experience without losing consciousness.
So 7 is nothing to sneeze at even under ideal conditions.
Okay, again, I agree this is not in the slightest practical, but also, again, a train accelerating is not vertical g, horizontal g tolerance is much, much higher than vertical g tolerance, especially "eyeballs in" and it increases greatly the less time it is for. Some early experiments showed untrained people could handle around 20g for less than 10 seconds. Also blunt force risks could be mediated almost completely by ramping the acceleration slowly, first reminding people to brace, then gently forcing them back in their seats. Again, ludicrous, nothing designed for comfort of human passengers is ever going to be designed to accelerate anywhere near that quickly and it's completely unnecessary anyways.
That test sled doesn't have the mass of a train car, let alone a full consist. It may very well be used on real trains, just not with such impressive results.
Yeah this link says most people can only take 4 to 6 g, but fighter pilots can take up to 9.
https://www.sciencefocus.com/science/whats-the-maximum-speed-a-human-can-withstand
As other commenter pointer out direction of force is important. Horizontal force is much less dangerous as it doesn't drain your brain of blood as much as a vertical one. If I recall correctly humans can survive 20-40 Gs of horizontal force compared to just 5-9 of vertical.
That's an expensive way to look inside your own skull.
Now we just need those inertial dampeners!
What a way to spill your cocktail...
I wouldn't want to travel in that, but it would be a good way to get shit into orbit without using rockets.
Railgun that shit up
Your move hyperloop.
So what’s the limit of the human body? That’s more than a couple g.
I don't know but it seems like the simple answer is to just not accelerate that fast. I doubt this was an attempt to imply that we should do this regularly. It's just a test to show what the technology is capable of. There's no real benefit to accelerating to that speed that quickly vs doing it over 30 seconds or longer.
You can absolutely accelerate this fast if there are no people on board. China probably wants safe autonomous cargo trains at some point.
What about eggs lol
Autonomous 500kph cargo trains would be fantastic.
Why would they transport eggs this way...? Fast (expensive) cargo trains would be used for valuable products. For example minerals, metals, computer chips.
Have you seen the price of eggs?
That's a US thing. Also, have you seen the price of everything?
There are non-transportation uses for it. Namely for weapons.
Call me a victim blamer, but if you let your enemy build a superconducting maglev rail from their territory to yours, I feel like that's on you.
Mr President, a second train has hit the Twin Towers.
You can't think any non-living thing someone would want to transfer beyond weapons? 😂
Definitely a “look what I can do” test and not a practical example of how the trams in Beijing will travel between stops. Though it would reduce trip time!
20-40 Gs for horizontal force.
Squishy.
How far did it travel in that 2 seconds?
If acceleration were constant (and my math is right), it would be 194m. We can assume due to air resistance being proportional to the square of the speed that acceleration will be more initially and less later, so realistically it will be >194m
Is this like those amusement park rides that use magnets to accelerate really fast?