Originally Posted by
Walter S
Hyperloop is not going to work on top of most existing routes including interstates, highways, or existing rail. The centrifugal forces will be too high. When people fly in passenger jets they are subjected to a maximum of around 0.5 G force. This is actually somewhat uncomfortable. But it's a force people endure typically only during take-off and they're used to it and expect it. You're pushed back in your seat for a couple minutes and if you're smart you won't be trying to take a sip of your coffee etc. at this time. But then once the plane gets a couple thousand feet off the ground and especially when it reaches cruising altitude you're usually back to no (induced) G forces (everybody feels 1 G at rest, the 0.5 I refer to is what's added on top of that).
Idk why you think hyperloop would need to entail g-force if it's a straight tube. It's not like you have to accelerate from 0-500 in 60 seconds.
You might think interstates and railroads are usually pretty straight but you have to put it in context. There are regularly "significant" turns on an interstate where you can feel the sideways forces of the turn. But on a hyperloop those forces would be totally unacceptable. Instead of just feeling it you'll be outright slammed sideways maybe even to the point of significant injury or even worse. If you're going let's say 600 MPH and you want your turn to induce only 0.5 G then the radius of the turn has to be over 15 miles! Picture a Nascar driver going thru turns on a track that's about a mile wide - he's strapped into the seat tight and undergoing a lot of stress and sunk into a angled seat AND going MUCH slower. And 0.5 G is still an induced force that's the maximum airliners subject you to by policy and for in-flight they shoot for more like 0.2 or 0.3.
The tube can go straight if there are no exits because it can just go through farmland, forests, timberland, etc. It would just be a tube on pylons; like a pipeline but without the risk of leaks.
It's not just turns that induce G forces it's also elevation changes. So building a hyperloop in California or Florida where it's at least pretty flat is kind of tolerable in that respect. But head up the east coast thru the mountains and it's another story. It would be too expensive to build a tunnel that's 1000 feet or more under the ground but that's what you're faced with unless you want the passengers to totally lose their lunch or worse.
I don't like drilling holes through rock. I think it is better to just keep it along the coast.