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Comment by imaginenore | Hacker News Reader

I'm not talking about the pod depressurization, which is indeed analogous to the plane, but is a separate issue, and is actually much worse than the plane (planes don't fly in near-vacuum, and can descend very quickly).

I'm talking about the tube pressurization, which is much much worse.

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So am I. You can still prevent explosive decompression in much the same way. If you provide reinforcing strapping for example, you prevent a minor puncture from turning into a massive tear and explosive decompression [EDIT: perhaps, I should say re-compression]. I.E. if air is leaking in relatively slowly, you will never get the violent pressure wave you are talking about.

That doesn't solve larger tears, like a terrorist shooting an RPG at it, or exploding something underneath, or flying a small plane into it. It's a very large target to secure compared to a plane.

Fair enough. However, I think you are underestimating the size of explosion that it would take to seriously damage something like this. Engineers will definitely think about things like earthquakes and accidental (or intentional) collisions (such as a truck hitting a support pillar).

I also think you are overestimating the number of terrorists running around with RPGs.

EDIT: Of course, when all is said and done, the additional engineering requirements to make it safe may also make it economically unfeasible, in which case, your original point about the dangers would be essentially correct.

Unfortunately vacuum tubes are very vulnerable, they would have to be ridiculously overdesigned to take even a small explosion or a truck.

Terrorist with an RPG is just an example, it can be anything - a drone with C4, somebody throwing a long string of burning thermite, or just a gasoline canister set on fire.

All of these things can cause the same loss of life on any current mass transportation system.

This reminds me of the people who were very vocal about automated cars needing to be perfect before they could replace human drivers. They seem to have quieted down as the technology gets closer to actual deployment. I suppose that will also be the case here if the hyperloop becomes reality.

Not the same loss of life. A large rapture will propagate through the hole vacuum tube at the speed of sound, likely killing everyone, not just one pod.

Also it's a much easier target. Planes are only reachable to the terrorists during takeoffs/landings. And even then, it's not exactly easy to hit a plane moving at 300mph with an RPG/truck/drone.

The rest of your argument about automated cars is the classic example of straw man.

You see, I didn't actually argue about automated cars, just noticed the similarity in the arguments.

And to address your original point in a horribly sarcastic way, if only someone had invented bulkhead technology...

Our current transportation system also doesn't solve terrorists planting bombs on rail lines or shooting RPGs at train cars or crashing planes into highway overpasses.

Not the same scale of destruction, not even close.

You might derail one train, if lucky, not every train on the track. We have defect detectors:

https://en.wikipedia.org/wiki/Defect_detector

Also trains, especially in the US, are much slower, and derailing one will probably kill a few passengers, but most will be fine. It's much more damaging to target bridges, which terrorists did:

https://en.wikipedia.org/wiki/Rafiganj_train_wreck (130 dead)

Crashing a plane into a highway overpass will do even less damage, because cars can stop very quickly when they see a problem.

Would building it underground largely solve these risks? We already build for natural disasters in mind- seems earthquakes would be the main issue in California, which structures claim to be "proofed" from.

The pressurization wouldn't be "explosive," there wouldn't be a pressure wave because a gradient of pressure would have to form between the atmosphere and the tube. Here's a playlist of videos rebutting this argument and many others:

https://www.youtube.com/playlist?list=PLSPi1JFx4_-Gz0Fm0qq2K...

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