'Hyperloop': L.A. to San Francisco in 30 minutes?
- %27Hyperloop%27 would use capsules that float on air in a large tube
- It would be immune to weather and would not crash
- Tesla CEO has had success with SpaceX%2C Paypal
Everything old is new again.
Partially borrowing a technology concept used by banks, entrepreneur Elon Musk introduced a design for a new transportation system that he said could shuttle passengers between Los Angeles and San Francisco in 30 minutes.
For now, it's an early, conceptual design at best -- a proposal for an idea that may never be built and likely gone unnoticed had it not been for the attention Musk receives for his other projects, including Tesla Motors and PayPal.
"The Hyperloop (or something similar) is, in my opinion, the right solution for the specific case of high traffic city pairs that are less than about 1500 km or 900 miles apart," he wrote on his blog Monday, following through on his previous hints for the project.
"Around that inflection point, I suspect that supersonic air travel ends up being faster and cheaper. However, for a sub several hundred mile journey, having a supersonic plane is rather pointless, as you would spend almost all your time slowly ascending and descending and very little time at cruise speed."
"The Hyperloop" is a system of people-sized pods that are moved over a network of air-free tubes built over or under the ground – much like the pneumatic tubes seen at drive-up windows at banks. Magnetic attraction would move the pods through the tubes.
To create a low friction suspension system for the pods traveling at over 700 mph, it would rely on a cushion of air.
"Air bearings, which use the same basic principle as an air hockey table, have been demonstrated to work at speeds of Mach 1.1 with very low friction," he wrote. "In this case, however, it is the pod that is producing the air cushion, rather than the tube."
The straight pneumatic approach would be problematic because the friction of a 350-mile long column of air moving at near sonic velocity against the inside of the tube is too "stupendously high."
Another approach -- using hard or near hard vacuum in the tube and then using an electromagnetic suspension -- would be too hard to maintain in a system of tubes with dozens of stations. "All it takes is one leaky seal or a small crack somewhere in the hundreds of miles of tube and the whole system stops working," he wrote.
On a conference call Monday, Musk said the project could take seven to 10 years for the first trial if all conditions are met. The system could cost as much as $6 billion, but he said that would be about one-tenth the projected cost of a high-speed rail system that California has been planning to build.
"I don't think it will provide the alternative that he's looking for," said James E. Moore II, director of the transportation engineering program at the University of Southern California.
Musk said he would publish an open-source design that anyone can use or modify. But if no one volunteers to actively take the lead on the project, he said he would build a prototype.
The Associated Press contributed.