CBS News

Published: Aug 12, 2013 5:05 PM EDT

LOS ANGELES (AP) - Imagine stepping into a car-sized capsule in downtown Los Angeles and, 30 minutes later, emerging in San Francisco.
    
Billionaire entrepreneur Elon Musk on Monday unveiled a concept for a transport system he says would make the nearly 400-mile trip in half the time it takes an airplane.
    
If it's ever built.
    
The "Hyperloop" system would use a large tube. Inside, capsules would float on air, traveling at over 700 miles per hour.
    
The air would be sucked by a powerful fan at the front and expelled at the rear.
    
Musk has said he's too busy to oversee the Hyperloop. Instead, he hopes others will take it on.

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