Audio Transcript:

Marco Werman: Let's move to another story that's been in the news this week. It's been kicked around at the water cooler because it is so tantalizing. Imagine traveling from San Francisco to Los Angeles in about 35 minutes. And you’re not in the air, either. That's the promise of a plan known as hyperloop. It's been described as a cross between the Concord, a rail gun, and an air hockey table, and it’s the brainchild of Elon Musk, known for his other innovative transports of delight such as the Tesla electric car and the private rocket company SpaceX. Tim De Chant, senior digital editor at WGBH with the program Nova has been looking into this. So you blogged this week, Tim, about the promise and peril of hyperloop and other high-speed trains. First tell us what Mr. Musk has come up with. How will the hyperloop actually work?

Tim De Chant: Well, one of the fundamental things about the hyperloop is it's two tubes that he would run down I-5 in California.

Werman: Big interstate.

De Chant: Big interstate. The capsules that run within them, each carrying about 28 passengers, and these tubes would be evacuated of air. They would be pumped down to 1/1,000th of an atmosphere of pressure, so that's very low pressure, and they're able to go faster because there's less wind resistance inside.

Werman: So it sounds like the old offices of the '50s and '60s. They would send messages and documents to other offices on various floors through this system of vacuum tubes. Is that the same idea?

De Chant: That's right, it's very similar. Those actually were powered by the air itself, whereas in this case, these capsules are powered by what are essentially regular electric motors, and that provides the power to move those capsules down that evacuated tube.

Werman: So in Japan, as you know, there's been years of work with the bullet train, which clocks in at nearly 200 miles per hour. The French TGV goes really fast. So how does the hyperloop actually advance the innovation of fast trains? Is it practical in that the United States could have something that rivals Japan and France?

De Chant: It's possible, but there are some limitations. Traditional high-speed rail can scale very well. So if you want to send more people between two cities, you just simply add extra cars to the train. Elon Musk's capsules are limited to 28 passengers each, and so if we wanted to increase above the six to seven million projected passengers he's saying this could carry, you probably have to start adding more tubes, and that would get unsightly and a lot more costly than he's predicting.

Werman: And what has Elon Musk kind of estimated this project would cost?

De Chant: He's estimated the entire project from San Francisco to LA would cost around $6 billion.

Werman: Going at such speeds, what's that going to feel like for the human body?

De Chant: It's definitely going to be an intense experience, I would have to guess. He's estimated that the maximum the hyperloop will exert on the body is about half a G, which is a fair amount of pressure exerted on the body, so I would think it would be relative to, say, a plane taking off, and turning would probably be more intense.

Werman: Pull back for a moment, Tim. You wrote that in 1893 the Empire State Express, presumably in New York, apparently attained 112 miles per hour. And then the rest of the world seemed to kind of take off, surpassing that speed. And now, Japan, France, Spain, they're all way faster on rails that the US. What happened?

De Chant: Well, there were a couple of things. We put a lot of money into the interstate highway system in the 1950s, and that's when our investment in rail started decreasing. Since that time, a lot of our rail system was privatized, after World War II still, and in the process of turning that into Amtrak, that of course was during the time of the Vietnam War, there wasn't a lot of money to sink into these systems. And also there just wasn't the appetite. People felt like the interstate system was good enough. A lot of people would like to say that our distances between cities are too great, but if you compare Japan to the east coast of the United States, they're actually pretty similar. So connecting the east coast would be really easy, California same, as well. I think it's just a matter of political appetite to get this done.

Werman: Policy-wise in this country as far as fast trains, California's just gone through an incredible argy-bargy getting a new high-speed rail linking San Francisco and LA and even environmental supporters called it a boondoggle, so where is this going?

De Chant: It's tough to say. Unless someone steps up and builds a full-scale prototype to actually test some of these principles it's very likely that it's not going to go anywhere.

Werman: Tim De Chant, senior digital editor at Nova here at WGBH. Thanks so much for coming in.

De Chant: Thanks for having me.