Once thought of as just a dream — is the hyperloop a real possibility?

Science Friday
Hyperloop passenger transport capsule conceptual design sketch. Credit: Elon Musk

Hyperloop passenger transport capsule conceptual design sketch.

Elon Musk

It sounds like science fiction: a hyperloop that propels passengers traveling from San Francisco to Los Angeles in levitating pods through a nearly airless tube. Their pace rivals the speed of sound. The journey takes only 30 minutes.

According to Brogan BamBrogan, former SpaceX engineer and now chief technology officer for Hyperloop One, however, the hyperloop is not only more than science fiction: it’s close to becoming reality. 

In May, startup Hyperloop One demonstrated a public test of its propulsion system, launching a metal sled to 100 miles per hour in just over a second.

Meanwhile, students around the world are submitting prototypes for passenger pods to SpaceX’s design competition, while rival company Hyperloop Transportation Technologies recently unveiled part of their own carbon-fiber pod design.

“There's no question it can work,” Bambrogan says. “You know, we say many times we could build a Hyperloop today, it would just be very expensive. So our goal is to not just bring this technology to the table, but bring it in a way that's just drastically cost competitive with every other form of transportation, as well as all the other opportunities that it brings with it: being ultra-fast, ultra-safe ... all green, no carbon, fully-sustainable. So all these things are important, but they're not important if we can't do it cost effectively.”

Bambrogan’s company has been working on developing all the core technologies that would enable a hyperloop to work: an electric motor, the aero-thermodynamics of a travel pod, a levitation system, power electronics, control systems. They hope by the end of 2016 to come together with a full system test that will allow them to test the technology in the range of 1-2 kilometers. That, however, is just the beginning.

“As our testing continues we're going to be going farther and faster,” Bambrogan says, “and adding, you know, turns and switching and pressure valves and all the other safety mechanisms that really go into the system.” 

The hyperloop is meant to be one of the safest transportation systems ever built. 

“It's a naturally safe system,” Bambrogan says. “Most transportation accidents occur either at grade crossings — which we don't have, weather events — which we're mostly immune to, and to operator error — which we're going to be immune to because we're a fully autonomous system. So, you take away those three things, that's over 90 percent of the accidents that happen in transportation. So that's gone already and then we have some other things that we're working on certainly, you know, we actually just hired a fantastic director of safety engineering.”

Bambrogan says the hyperloop will operate more like a car than a train. 

“We aim to packetize the delivery of certainly people or cargo,” Bambrogan says. “So what that means is, it's not going to look like a train, it's going to feel more like a car in terms of, you know, nobody ever arrived at their car early because your car leaves when you want to leave. So as we create kind of small units that are discrete, we can send people exactly when they arrive at the terminals and we also can send them directly to their final destination.”

There are still, however, many engineering challenges HyperLoop One faces, one of them being designing the vacuum system the pods will use to move. 

“It's not a hard vacuum,” Bambrogan says. “Maintaining a hard vacuum like they have at CERN the Super Collider takes a lot of energy and it's really hard to get that last mile. So we're kind of operating in what we think is sort of the sweet spot of energy usage where we're at low pressure — low enough that there's very little aerodynamic drag, but also, you know, high enough that it's easy to maintain. Not only to get to but even if there's leaks or any other things that kind of happen in a robust system. So we really think we kind of are going to be operating in the sweet spot of the vacuum.”

This article is based on an interview that aired on PRI's Science Friday.