hyperloops: a sleek, futuristic, high-concept solution in search of a problem
When Elon Musk mentioned the idea of a train in a vacuum chamber speeding across the deserts of Southern California at nearly the speed of sound, he started a new craze and at least a dozen companies around the world trying to bring this extremely ambitious idea to life. And it does make sense why the idea is attractive, especially if you’ve experienced the convenience of high speed rail service and can see how easy access to certain hubs could result in major economic benefits depending on the location of the stations.
Plus there’s the refreshing energy of a billionaire chasing a truly big vision instead of plowing his profits into yet another burrito delivery app, as tech world’s most powerful investors are often wont to do, and a lot of people are getting really excited about their new high speed futures. Hyperloop advocates are already engaging in sleek PR to get governments to wave some of the many regulations the companies they’re backing will have to face, acting as if the technology is ready, they just need the land and permits to start building the stations and tubes.
But the fact of the matter is that even if we were to wave away the permits, regulations, and land rights issues, the fundamental idea behind hyperloop travel is wildly impractical. Shooting a capsule in a vacuum tube works really well on small scales, but when you blow it up to roughly the size of a Japanese shinkansen car and try to make it go about three times as fast, the physics become far more challenging while the risks to both passengers and infrastructure grow exponentially. And many of the customers to which current startups are pitching their vision might not actually need their services.
huge energies mean huge risks and costs
While hyperloop enthusiasts frame the technical challenge as just putting the capsule carrying the passengers or cargo in a tube, depressurizing it, then using magnets to shoot it down a more or less straight tube with a few large curves, the practical reality is a lot more complicated. The materials from which the hyperloop tubes will be made would expand and contract as the temperatures rise during the day and fall at night, as well as from the heat of the sun shining down on it, something that happens close to 300 days per year in the American Southwest.
Add up the subtle expansions and contractions, and you’d get hundreds of meters of movement along the system for which there doesn’t seem to be much of a plan, and which would require thousands of vacuum seals able to move with the tube. Failure to allow for that expansion means that the vacuum will be broken and air will rush in with the force of an exploding bomb, literally. Just two pounds per square inch, or psi, can shatter a house. Four will bring down anything not properly reinforced. Ten can level a skyscraper and quite literally tear a human to pieces with air movement alone.
Now consider that the pressure differential between the hyperloop tube and the air around it at sea level is 15 psi, so a ruptured or suddenly unsealed tube would be on the receiving end of the opposite of explosive decompression with energies comparable to the shockwave of a tactical nuclear blast. It’s almost needless to say that every passenger would be dead moments after such an event. Same goes for any other incident that can rupture the seal, i.e. earthquakes, mudslides, or something crashing into the track, accidentally or on purpose if we account for potential terrorism.
Likewise, traveling at the speed of sound means that emergency braking will be extremely difficult and the G-forces involved might either have to be extreme, risking passenger injury, or too slow, meaning that the capsule won’t stop in time. There would also need to be ways of quickly getting a stopped capsule out of a tube and instantly shut down traffic behind it, otherwise it could get rammed by a trailing capsule, killing everyone involved instantly, or the airtight capsule could be stuck in the tube for too long killing everyone involved slowly by hypoxia. Very few of these issues seem thought out, and they’re very much the sort of thing regulators should be examining in great detail.
do we really need a hyperloop?
Basically, if everything goes right, the tracks don’t move a micrometer, there’s no emergency, no issues with power, and no natural disasters that might affect the hyperloop tubes, everything should work more or less perfectly. But the moment anything disrupts this precisely calibrated system, and it will need to be exactly that, we’re looking at high energy carnage. So why are we taking these risks and working so hard to find a solution to them? We already have airplanes to travel quickly, and there are high speed rail designs like the shinkansen, which might not be quite as fast, but would be more comfortable and far, far safer.
Why build an untested, risky system when we can create aerodynamic high speed rail using proven magnetic levitation technology and safety features where there’s demand for it? As a bonus, we know we can get them moving even faster than they are now with little additional risk so we can design their routes with these maximum speeds in mind. The same goes for cargo, another line of business with less hazard to life, if not property, hyperloop companies want to take on. Logistics experts don’t know why they’d want to send their wares at nearly the speed of sound outside of cases involving perishable items or human organs.
Even then, they have refrigerated transport for said perishables, doctors give them special devices to keep organs stable enough for implantation, and most of their wares seldom need to get to their destinations that quickly. They might also look at the risks of using a hyperloop and decide against it because a high speed accident inside a tube would be a catastrophic loss so it’s unlikely their insurers will allow them to proceed. On top of this, much of today’s shipping is global, so a hyperloop won’t solve potential delays with customs and container ships, just the final segment of their journey because a trans-oceanic hyperloop will be several orders of magnitude more difficult than dry land ones we haven’t even built yet.
will anything come out of the hyperloop idea?
It seems unlikely we’ll have hyperloops any time in the foreseeable future. It may be a fun and exciting concept, but it’s really a solution in search of a problem, much like self driving cars. The companies eager to build one are banking on the idea that people will want to be strapped into a capsule, shot down a claustrophobic tube at roughly 500 to 760 mph while hoping nothing at all goes wrong in an extremely delicate, high energy system for the half hour they’d be in it, and logistics companies will want to take the same risk to deliver fewer goods they already have no problem delivering in the same manner.
At the same time, they’re probably hoping no one asks why we’re not building Japanese and European style high speed rail systems proven to work extremely well and far more safely instead, hoping their style and seemingly art-deco inspired minimalist renders win over logistical substance, which can also summon very stylish concept art in its PR blitz. None of this seems like a recipe for success in the long term and illustrates the problem with merely relying on having a bold vision. It’s not enough to dream big. You also have to have address real problems for your dreams to become reality.