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Loop and Hyperloop are two completely different things. Loop is Tesla cars in a tunnel, and Hyperloop is theoretically capsules in evacuated tube. The former is not very good way to get around city, and the later is a not very good to get between cities.


"if" is doing a lot of heavy lifting in that sentence.

The criticisms of TBC fall into three camps: (1) this is terrifyingly unsafe, if a vehicle catches fire in those tunnels the occupants can't even open the doors and no vehicle behind them has a way to safely evacuate either; (2) they are still really expensive, like all other tunnels; (3) this compared poorly with all other modes of transport on every measure.


Thanks for replying with some depth-specific concerns.

Okay, so perhaps the worst case scenario is only goods are shipped in the tunnels - taking all semi-trucks off the roads for at least the major long-haul routes?

All-or-nothing thinking without critically thinking or brainstorming through how adaptations for adoption could be made isn't helpful.

Re: Safety

Perhaps battery tech that eventually is safer than currently driving a vehicle, perhaps even safer then with the casualties from airplane crashes, or other solutions like before entering the tunnels everyone is provided emergency kit/safety-oxygen masks/goggles, etc; and maybe necessary for doors that have an emergency "blowout" handle to pull and have doors pop off their hinges? I'm not sure you're correct about being unable to open and get out of a vehicle in such the tunnels.

We go through security checks, etc, at airports to save time - what level of "inconvenience" are people willing to implement or follow if a ~5 hour drive can turn into say a ~30 minute ride in a Hyperloop?

Also, in the Hyperloop almost vacuum state that's planned, fire will be less of a problem - and perhaps a safety system could be implemented, especially if everyone is temporarily given an oxygen mask-goggles for each longer ride or all rides, that at certain points a fire extinguishing-suppression system could be implemented where non-oxygen gases are flooded into the tunnel between the point a fire is detected?

Arguably so long as cost of implementation is less than or the same cost than current existing infrastructure costs, where the time savings are arguably up to invaluable - but a cost per ride for each person using the system will be determinable, then it can be a great alternative especially with the positives of how it allows transport regardless of winter weather conditions, etc.


> Okay, so perhaps the worst case scenario is only goods are shipped in the tunnels - taking all semi-trucks off the roads for at least the major long-haul routes?

So, in this scenario, you could only do that if each major long-haul route had a tunnel. And you made the tunnel wider, as the current tunnels — where the only cost-saving TBC has demonstrated of any kind so far is by limiting the size — aren't big enough to fit an American standard intermodal container, and only just fit the ISO containers (with so little margin you have to care about the turning circle even if you could fit the carrier into the circular gap around the boxy cross-section). And that's without also considering that current trucks definitely don't fit no matter which size standard is considered, so either you'd need the tunnels even wider or you'd need something custom-designed to fit.

High axle weights cause more damage to the surface, which is really bad for a tunnel where you can't just go around a pot-hole, so you want something hard-wearing, something like steel. Even if you use maglev, looking at current maglev research trains, you've got a speed-up zone where you still have contact.

But you don't need to cover the whole surface in steel, because unlike a road where the vehicles might move sideways, this is so tight that there's only one place for the wheels to even be. And if you do that, you could get rid of the batteries entirely by hooking these steel wheel-paths to the mains.

But then you can save money on the vacuum systems, because if you put all the ISO containers in a row: as each container will be in the slip-steam of the one ahead of it, a chain of 10 will have the same impact as a 10x reduction in air resistance.

Oh look, it's now either a railway or a subway depending on if you bother with the "underground" part.

> I'm not sure you're correct about being unable to open and get out of a vehicle in such the tunnels.

The pictures I've seen show negligible clearance between the bottom of the car doors and the curve of the wall. Also, I talked to a civil engineer.

But if you're talking about an evacuated tunnel, then leaving is lethal even if it's physically possible.

> We go through security checks, etc, at airports to save time - what level of "inconvenience" are people willing to implement or follow if a ~5 hour drive can turn into say a ~30 minute ride in a Hyperloop?

Hyperloop in particular (as in, not just the tunnel) is about the speed, so it only makes sense to wait 30 minutes for security etc. if you can go sufficiently faster than a car would have. But is this a point-to-point system in a network that connects everywhere to everywhere else, like a road, or a hub-to-hub system? If it's the former, then those 30 minutes could've taken you 15 miles at residential speeds or 35 miles at motorway speeds (in the UK, I don't know US norms) — a delay like that means there's no point even trying to make it like the road network, so QED it will be hub-to-hub; but if it's hub-to-hub, you now also need to factor in the time it takes to get from wherever you are to your closest starting hub, and in reverse at the far end the time between your ultimate destination and its nearest finishing hub in addition to factoring in the delay for security.

But hub-to-hub can't replace all semi-trucks off the road — at least around here, they go to each supermarket, and I've got something like 8 supermarkets with articulated lorry loading bays within a 15 minute walk from my apartment.

Given the big-rigs aren't going away without an absurd degree of extra infrastructure build-out (never mind tunnelling, that kind of density is more like "raise city by 10 meters and rebrand old roads as 'hyperloop'"), if you're going to have a setup with hubs that far apart, why not just use a plane (for long distances, with security delays) or a train (for shorter distances, without the hassle of security)?

> Also, in the Hyperloop almost vacuum state that's planned, fire will be less of a problem

Not so, li-ion can undergo runaway thermal failure even in a total vacuum. And a vacuum is a great insulator, so that will stay hot for a long time. I'm having trouble finding how hot these get (the numbers are all over the place, and are in any case mostly about car fires), but the lower ranges are still in the "melt aluminium" range of temperatures. And if this is in the configuration where you take a car onto a pod or other travel vehicle, that's in the section with air anyway. If you can't take your car with you, it looks a lot like conventional public transport.

> Arguably so long as cost of implementation is less than or the same cost than current existing infrastructure costs, where the time savings are arguably up to invaluable - but a cost per ride for each person using the system will be determinable, then it can be a great alternative especially with the positives of how it allows transport regardless of winter weather conditions, etc.

Those conditionals are load-bearing.

The creation of a tunnel is generally more expensive than the same length of railway. Where land is expensive enough to make up the difference (e.g. old cities), or where terrain adds complications (go from one side of a mountain range to the other), tunnels are already used and quite often (but not always) rails are put in those tunnels — with a lot of safety considerations and backups for when things inevitably do go wrong, many of which can't work in an evacuated tunnel. TBC hasn't made any newsworthy dents to that price (sadly), all they've done to reduce costs is make the tunnels so narrow they barely fit a car.

Busses also reduce congestion on surface roads, just by having more people per square meter. Down-side is the same hub-to-hub consideration, up-side is flexibility when one route is unavailable for repairs.

For long distances where high speed is the critical issue, aircraft already exist. Extra cost-saving: no need to evacuate the tunnel, gravity already did it for you. And if you need to rapidly leave the evacuated section, not only do the oxygen masks drop, so does the plane — and, unlike in a tunnel emergency, this doesn't cause all the planes behind it to get stuck.

If weather is a critical issue, then you would need an everywhere-to-everywhere network, but as previously mentioned, that doesn't work with a 30-minute delay to get started — to give a concrete example, 30 minutes into my commute is when I get off the underground and walk the rest of the way to my office.


Or they could do one bigger tunnel and put a train into it like every other city with a functional public transport?


I like how the Vegas Loop tunnels are almost the same diameter as the London Underground deep lines. Glasgow subway is even smaller. Which means the tunnels are big enough to run metro and carry lots of people.

It would be better to use larger tunnel, buy normal sized trains, and keep tall people from hitting their heads. It would also make sense to use one of the automated systems instead of trying to build pod system.

It is also curious that Musk always want to do his way. Cause there is company that makes automated pods used at Heathrow. They should work for the current service and wouldn't be Tesla 3 with driver.




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