Link: https://www.youtube.com/watch?v=ePm79q-wYM0

Whiplash, Japan

Thinking of pilots in jets going at several times the speed of sound, I'd say yup.

Why do the crash dummy's have nipples?

Don't you need special training for that? And also a special suit that squeezes your body to keep your blood in the right place?

And its usually loaded in line with your spine, rather than sideways.

You can survive 20G horizontally (chest to back). But whether that's safe at a population level as a regular mode of transportation is a different question… Direction of force really matters here.

Generally up to 4G is considered reasonably safe for most people, though it will still put strain on your organs. I still wouldn't put grandpa through it everyday.

The question was about surviving it, not getting past it unscathed.

you do not need any special training or equipment to survive any particular speed (or velocity), like the speed of sound, as long as you get to that speed comfortably.

you DO need special training and/or equipment to survive extreme G-forces (acceleration). Acceleration says nothing about what your speed/velocity is, only how quickly it’s changing.

For example, think about astronauts taking off in a rocket. At launch they experience extreme g-forces as the rocket makes them accelerate upwards. But once they reach the orbital or escape velocity they need for their mission the rocket turns off. They stop accelerating and feel no g-forces at all (micro gravity), but they are still cruising along at an extremely high velocity.

Those are nipular sensors meant to measure any friction and/or torsion caused by the seatbelt.

What is this video of? I just rode this exact train and it only reached 1/10th of this speed (200KM/h)

Edit: ah, a simulation. The stop looks brutal and this is traveling faster that the earth is spinning funnily enough.