Elon Musk unveiled plans for his Hyperloop transport system — a steel tube that would shoot aluminum passenger pods at up to 800 miles per hour between cities — and invited engineers to help him build out the design.
Musk said a line from San Francisco to Los Angeles would cost between $6 billion and $10 billion — about one-tenth the cost of the proposed California high-speed rail system for a technology that would carry passengers four times faster.
For Musk, creating an entirely new mode of transportation would represent another challenge to juggle while he develops electric-car technology at his Tesla Motors Inc. and works on commercial-cargo space venture SpaceX. Last week he said he was too "strung out" to focus on SpaceX. But today in a conference call, he said he thought Hyperloop would develop faster "if I created a prototype and helped get this going."
Musk laid out his Hyperloop vision in a 57-page document that describes an elevated steel tube running from the Bay Area to Los Angeles. As envisioned, Hyperloop could carry 840 passengers per hour in sealed capsules carrying 28 people each. That capacity would be more than sufficient to transport all of the 6 million passengers traveling between Los Angeles and San Francisco each year, he wrote.
The low-pressure tube, elevated on columns spaced about 100 feet apart, would contain passenger pods mounted on "thin skis made out of inconel," a SpaceX alloy capable of withstanding high pressure and heat. The pods would move on an air cushion. Electric linear accelerator motors along the tube would provide propulsion.
Air intakes on the front of the pods would take in air, and a compressor motor in each capsule would redirect that flow to help the unit float on air ball bearings.
Musk said the pod could travel just under the speed of sound to avoid sonic booms. A ticket would be "much cheaper" than a plane ride, Musk told Bloomberg's BusinessWeek.
The Hyperloop would employ an emergency brake for safety purposes, Musk said.
"The safe distance between the pods would be about 5 miles, so you could have about 70 pods between Los Angeles and San Francisco that leave every 30 seconds." He likened the trip to "getting a ride on Space Mountain at Disneyland."
Musk, whose gift for promotion has helped push Tesla Motors shares more than fivefold to $147.38 percent in the last 12 months, has also captured the public's imagination with his mass-transit concept. "Hyperloop" shot to the top of Web searches today, according to Google Trends.
Musk said he had been thinking about mass transit for a couple years, and that shortcomings he sees in California's planned high-speed rail project inspired him to lay out his initial plans for Hyperloop. He noted that regardless of how technologically dazzling Hyperloop would be, it has to outperform current modes of transportation to make sense. Rod Diridon, executive director of the Mineta Transportation Institute in San Jose, agreed.
"Success depends on the development of a working demonstration system that can compete with the other current international modes in terms of environmental impact, cost of construction, operational characteristics and safety," Diridon said in a statement.
The excitement he has created with the unveiling initially drowned out some of the practical considerations. Musk himself pointed out several design problems his initial plans haven't worked through.
"I have to say on my first reading of it, it didn't get deeply enough into the issues I care about," he said.
Kesten thinks most travelers would be uncomfortable (to say the least) traveling at 0.5 G, the maximum speed of acceleration that Musk would expose passengers to.
Another concern revolves around the air drag that would occur between the tube and the pods.
Elon Musk's explanation "seems a little goofy to me," said Kesten, who nevertheless remains a supporter of the forward-thinking entrepreneur.
"That's where it has to start. It won't be physicists who get this off the ground. It'll be some engineers who will see if the idea of pushing air from one side of the capsule will work," he said.
A thorough demonstration would be the first step required to get the Hyperloop up and running.
"What would be cool is if this got a couple engineer-type people excited to go and do some small-scale testing of these ideas," he said. "I still think he's a visionary. Sometimes, pushing people towards a place where nobody thinks we can go is a good thing."