Elon Musk, billionaire and entrepreneur, is a man of many enterprises. Some, like online payment site PayPal or the solar panel giant SolarCity, sound like sensible, practical responses to modernity. Others, like his idea for a pan-American network of magnetically levitating trains, seem, at first glance, less so.

Musk first laid out proposals for his Hyperloop transport system in 2013, calling it a “cross between a Concorde and a railgun and an air hockey table”. Passenger capsules would whizz back and forth between LA and San Francisco along two parallel tubes (the “loop” of the train’s name):

Unfortunately, his original cost estimate of $6bn for a line between Los Angeles and the San Francisco Bay Area was deemed a massive underestimate by infrastructure experts and economists. 

So far, so unfeasible, and after the initial proposals were first released in 2013, everything went quiet for a bit. As it turns out, Musk was rounding up a group of 100 part-time engineers to conduct further research in exchange for stock options, and in December, they finally released a document outlining their progress. Then this happened: 

Musk later told the Texas Tribune that the test track would be privately funded. And, since he is a very rich man, it looks quite possible that the track will actually be built sometime in the not-too-distant future.

In summary, it might be time to start taking the Hyperloop seriously. In that spirit, here are some takeaways from the engineers’ 76-page briefing document .  

It would be the fastest train in the world. 

The current fastest train is the Japan’s maglev, which also operates using magnetic levitation technology but runs at a maximum speed of 602 kmh. The Hyperloop would double this speed by using the same magnet technology (which propels the train along as it floats above a magnetic rail) inside a vacuum, so friction would be reduced to a minimum.

As a result, the engineers’ calculations are based on the idea that passengers will move at 470mph. 

The grand plan is very grand.

Musk originally proposed a line between LA and the Bay area as an alternative to a planned high-speed train on the route. Now, the proposed Hyperloop routes look like this:

Click for a larger image. Image: Hyperloop Transportation Technologies

Gulp.

To show the scale of their ambitions, the group have produced mock-ups of the trains grandly passing in front of various US city landmarks. Here’s Washington DC:

And New York:

They’re hoping to keep prices down (but they might not be able to). 

If the project sticks to the original $6bn budget, ticket prices between LA and San Francisco would be around $20-$30, with higher prices on longer routes. This would be dramatically cheaper than US air or rail travel – a flight from LA to San Francisco, for example, is $100 minimum. But, the report admits, if the budget for each line rises higher, ticket prices would need to rise too to cover costs. 

The capsules won’t have any windows, and you won’t be able to go to the toilet (probably). 

In order to reach that enormous speed, the capsules will whizz along inside a thick, vacuumised tube, which means there won’t be any pleasant views of the American countryside.

You’ll also need to keep your seatbelt on at all times – so no loo trips. 

The document suggests several solutions to this problem, including a toilet in business class for “emergencies”, or this somewhat horrifying suggestion: 

One solution could be to allow each seat to be separated and isolated from the others and use a system integrated in the seat for emergency issues.

So you’d essentially be sitting on a toilet for the entire trip. 

A capsule leak could be catastrophic.

One issue with whizzing capsules along an airless tube is that the tube will be, well, airless. If the capsule’s walls sprung a leak, or if passengers needed to make an emergency exits, pressure conditions would be a bit like being in space. From the report:  

None of the emergency measures commonly used even by military pilots… are enough to avoid severe hypoxia and traumas related to the decompression.

It continues, somewhat more cheerfully:

Luckily we are not in space but on earth and believe we can find systems to compensate the pressure fast enough.

We’ve watched enough sci-fi films to know that this should be very, very high on the priority list.