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Comment by skywhopper | Hacker News Reader

What will the actual humans-per-hour throughput of a practical hyperloop implementation? My understanding is that although the technology may work, it's unlikely to be economically feasible given the actual realistic capacity. How is this superior to high-speed trains?

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Even if it’s respectably higher than anything existing, it can only source passengers from hub origins and drop them at hub destinations, leaving last-mile problems yet to be solved. Spokes will be needed at destination hubs, that allow for individualized selective destinations for the last mile.

Meanwhile if a city needs 3/4 of it’s workforce through the door by 9AM, congestion at each hub still occurs, and rush hours aren’t actually alleviated, only spread around. Hub stations will be the same horrible kind of place train stations, bus stations and airports are, unless a new conceptualization of origin sourcing and destination arrival is brought to the table.

The only new aspect that a hyperloop adds to the equation, to change the game is that, theoretiacally, longer distances can be negotiated, permitting any given urban center to import from greater distances than before, and urban residents can interchange between hubs without 500MPH aviation.

Of course, for those promises to hold true, tubes must be cut, and track laid within them. Every mile of interconnection adds compelling power to the principle of the concept. Individual point-to-point connections are meaningless, if there are not many points connected, and the distances aren’t longer than was previously realistic.

Hyperloop ultimately is about a way to bring the advantages of high altitude jet travel to much shorter regional hops, essentially bringing the stratosphere down to sea level. It's not really about mass transit within a city. Don't need 500mph for that.

The throughput of hyperloop is equal to ~3-4 trains per hour of capacity, assuming you completely maximize utilization of the infrastructure (that's ~30s dispatch intervals). This is assuming you could safely dispatch pods at 30s intervals, which is a contentious issue to say the least. For HSR, you'd generally see 6-12 tph for intercity trains, although the tracks themselves can generally handle 24-30tph (depending on how good your signalling is).

Effectively, hyperloop is the capacity of a point-to-point transit system (e.g., airline) with the infrastructure requirements of a train network, or combining the worst features of both systems. You'd have to bore city-center tunnels for every city you'd want to connect to, as opposed to being able to share those tracks (the fact that you can't share intercity rail with commuter rail is a big reason why maglev generally doesn't make economic sense).

It's completely dependent on how long the cars are. You could do hyperloop* with 1,000 passenger trains just fine. The real limit is utilization, and smaller cars are easier to design.

The real benifit is simply speed, it's faster than aircraft and no need for extensive security as you can't hijack trains.

* Not that the term seems to refer to any specific design at this point.

I was going by the original Hyperloop concept as opposed to vactrains. It can sometimes be hard to tell if someone means "Elon Musk's 21st century idea" or "yet another retread of a 19th century proposal" when Hyperloop is mentioned, but I tend to err on the side of the former, since most of those adherents are extremely adamant that the differences means it's better.

You're right in that vactrains are essentially no different than HSR, and that's basically because vactrains are just ultra-HSR. There is some issue about using maglev propulsion versus regular electric locomotive, but that's mostly about being able to share infrastructure in inner-city portions.

A bomb is going to be just as horrifying on a Hyperloop as it would be on a plane - killing hundreds and destroying even more infrastructure then a bomb on a plane would. Security is still a need.

It does not need to be impervious, just no better a target than a sidewalk.

I don't think a reasonable sized bomb is going to do much more than kill people in a single car. So, sure some people would die and it would cause some damage, but not even close to hundreds. Basically, the same risks as someone blowing up a buss, which has no real safty checks.

If a bomb causes a breach of the loop, what happens to the other cars? If cars are going rapidfire, what happens to the next car if one car stops faster than braking speed, or causes a deformity of the tunnel that obstructs it?

You certainly can hijack trains [1]. If you plan on trying to get away, it's obviously not a very smart choice.

[1] https://en.wikipedia.org/wiki/1977_Dutch_train_hijacking

Seems to be the big problem with this. I can't see it being anywhere near a high speed train. The distances between pods would have to be (very) significant and the pods themselves will be pretty small I bet as it's in a pressurised tunnel.

Other problems include branches and junctions which normal railways can do with no problem.

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