Elon Musk's 'Hyperloop': More Details Revealed

astroengine writes "Entrepreneur Elon Musk revealed details today about his concept for a high-speed transportation system he calls the Hyperloop. After tweeting that he'd pulled an all-nighter preparing for the announcement, Musk told Businessweek that the design could transport people as well as cars inside aluminum pods that move up to 800 miles per hour through a tube. The tubes would be mounted on columns 50 to 100 yards apart, not interfering with land needs because it would essentially follow major highways, such as I-75 in California."

Comments

Re:very unfeasible

[dgatwood]

Rail is far more efficient. The track itself is cheap, the major cost is actually buying the land. There is very little friction resistance as well.

That's actually a problem past a certain speed. At least in the U.S., they don't allow trains to travel at high speeds in populated areas because they can't usefully stop if somebody walks across the rail. They can't stop because there is very little friction possible. With a closed tube, you don't have that risk, so you can shoot through downtown L.A. doing 250 MPH.

Re:How safe would this be?

[Guspaz]

Consider first that sufficiently large deflection would result in the immediate emergency breaking of all capsules. There is also the consideration that earthquakes don't travel instantaneously, which means there is some advanced warning between an earthquake being detected and an earthquake reaching the hypertube. There is also the capability of the dampers on the pylons to absorb a certain amount of movement. These things combine to give sufficient time to decelerate the vehicles.

Consider this: earthquakes are a far larger problem in Japan (both in intensity and frequency), and there are similar consequences to deflecting the rail of a high speed train (the danger there is derailment). Even a stationary train can topple in an earthquake, much less of a concern on the hyperloop. Japan has never suffered a fatality on a shinkansen due to earthquakes, over the past half century. The hyperloop's emergency stopping distance would be vaguely similar to that of the shinkansen. The shinkansen emergency braking from top speed takes about 40 seconds by my math, and the *normal* deceleration from top speed of the hyperloop would take 70. If it decelerates faster than normal for emergency braking, it could potentially even stop faster than the shinkansen.

why not start smaller?

[stenvar]

Building a hyperloop from San Francisco to Sacramento, or San Francisco to San Jose, would be useful and much shorter and cheaper.