So here’s the exciting subject line of an exciting email I received yesterday:

Subject: EMBARGO: Hyperloop Construction Begins

Surely… it couldn’t be. Could they finally be-

Good morning,

Hyperloop Transportation Technologies is making an important announcement regarding Hyperloop construction this week. I can send you more details in our press release and accompanying video currently under embargo until 6 AM PST Tuesday, March 21, 2017.

It could! They’re actually doing it! They’re building the Hyperloop!

Strangely, though, the original email ends there. To find out more, you have to email back to ask them nicely to send you more details.

So I did just that, and this is what I learned.

Hyperloop Transportation Technologies (HTT) has begun construction of the world’s first full scale Passenger HyperloopTM Capsule. This first capsule is the culmination of over three years and thousands of hours of design, research, and analysis.

Oh. So they’re not building an actual Hyperloop. They’re just building a… pod.

Construction is underway for delivery and an official reveal in early 2018 at HTT’s R&D center in Toulouse, France for integration and optimization.  The capsule will then be utilized in a commercial system soon to be announced from the ongoing negotiations and feasibility studies currently taking place around the world.

There may be a reason they’re not building an actual functioning Hyperloop yet. It’s this: it’s not altogether clear that the Hyperloop is ever actually going to be built at all.

Actually, that’s not fair. To paraphrase the Guardian technology correspondent Alex Hern on a recent episode of our podcast, some Hyperloop, somewhere, probably will be built: there are people and countries out there (*cough* UAE *cough*) with more money than sense. Nonetheless, it’s far from clear it’ll ever be competitive with something rather less sexy and futuristic like high-speed rail.

To explain why, we need to go back to the basics. The Hyperloop is, basically, a tube from which 99.9 per cent of the air has been removed, to create a near vacuum. Inside it, pods would use magnetic levitation – kind of like the pucks in air hockey – to float very slightly above the tube itself.

A concept drawing of a Hyperloop tube. Image: Edit1306/Wikimedia Commons.

The result of this would be no air pressure, no surface tension, much higher acceleration and much higher speeds: up to 760 miles per hour, with an average of around 600 mph. In the original paper in which Elon Musk proposed the Hyperloop, he suggested that pods could get you from Los Angeles to San Francisco – a distance of around 350 miles – in about 35 minutes. That’s fast.

All this sounds like science fiction. It’s not. This technology exists.

Nonetheless, it’s not clear whether building the thing will ever actually be plausible. Musk’s proposed route would use the median of Interstate 5 – that is, the big gap between lanes in the middle of a motorway – on the grounds that this would both cut the cost of the project, and reduce political opposition. But it’s not clear it would do either. To quote the transport writer (and occasional CityMetric contributor) Alon Levy:

In reality, an all-elevated system [which is what Musk proposes with the Hyperloop] is a bug rather than a feature. Central Valley land is cheap; pylons are expensive, as can be readily seen by the costs of elevated highways and trains all over the world.

So: the technology to accelerate those pods to 700mph exists. The technology to build the tubes to put them in at any remotely sensible price does not.

Oh, also, it’s not clear whether being shut into a windowless pod and accelerated to 700 miles per hour is the sort of thing that anyone might actually want to do.

While we’re nit-picking, central California is a bit earthquake prone, and the last thing anyone needs when travelling down a tube at 700mph is for the tube to snap open, firing your pod into the neighbouring hillside like a bullet.

At any rate – the Hyperloop is entirely possible, technically. That doesn’t mean it’s vaguely feasible as a means of actual transport.

So it’s all very nice that Hyperloop Transportation Technologies is working on the design for its pod. It’s a step towards wherever it is that we’re going. But until they come up with a plan for cheap pylons or concrete that doesn’t expand or contract in the California heat, I’m going to remain suspicious about the phrase “Hyperloop Construction Begins”, especially when the press release it’s attached to is not, in fact, about Hyperloop construction beginning.

Or, to quote the boy wonder:

Anyway, if you’re interested, here are some details about exactly what it it that Hyperloop Transport Technologies is building:

HTT’s passenger capsule is being built in collaboration with Carbures S.A, a leading expert in fuselage and advanced materials construction in both aeronautics and aerospace.  The final specs for the capsule are:

  • Length: 30 meters (98.5 feet)

  • Diameter: 2.7 meters (9 feet)

  • Weight: 20 tons

  • Passenger capacity: 28-40

  • Speed: Up to 1223 km/h (760 mph)

And if you want to know more about the Hyperloop, and why it’s a bit iffy, listen to Alex on our podcast.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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