Billionaire investor Elon Musk has unveiled plans for a "Hyperloop" transport system he hopes will one day shuttle passengers and cars between Los Angeles and San Francisco travelling faster than the speed of sound.

After almost a year of speculation Musk outlined his plans for the system Monday in a blog post and a 57-page PDF. People and cars would be transported between cities inside aluminum pods traveling a speed of up to 800 miles per hour inside elevated tubes. In a conference call Musk said he had been inspired by the pneumatic tubes used for transporting mail around some buildings.

The PayPal founder has long been obsessed with transport and used his fortune to develop electric-car firm Tesla and the private spaceflight company SpaceX. Musk has previously said that Hyperloop will be a "cross between a Concorde and a railgun and an air hockey table."

According to Musk's blog post the Hyperloop could act as a fifth mode of mass transport after planes, trains, cars and boats. The billionaire said he was not looking to build the system himself although he was "tempted" to build a demonstration model.

Outlining his plans in an interview with Bloomberg Businessweek Musk said the tubes would be elevated on columns 50 to 100 yards apart and run alongside California's Interstate 5 highway. "You just drive on, and the pod departs," Musk said, estimating that the system could be built for $6bn with people-only pods, or $10bn for the larger pods capable of holding people and cars.

Musk said he envisioned 70 pods could travel between Los Angeles and San Francisco leaving every 30 seconds inside low pressure tubes designed to minimize friction and allow higher speeds. "It's like getting a ride on Space Mountain at Disneyland," he said.

The system would be a closed loop, designed for cities less than 900 mile apart that have high levels of traffic.

Musk described the Hyperloop system at a conference in May and said that the solar-powered system would allow passengers to get from Los Angeles to San Francisco in less than 30 minutes. Such a journey would be five hours shorter than the time it would take to drive.

But the investor is unlikely to build any such network himself and is hoping that others will now take up the challenge with him. Talking to Tesla investors last week Musk said he had "shot myself mentioning Hyperloop, because obviously I have to focus on core Tesla business and SpaceX business, and that's more than enough. But I did commit to publishing a design and [inviting] critical feedback to see if people can find ways to improve it. Then it can just be out there as kind of like an open source design that maybe you can keep improving."

Musk said he was inspired to look at the project after reading about California's high-speed rail project, a project he has called "a bullet train to nowhere."

In his blog post Musk wrote:

The underlying motive for a statewide mass transit system is a good one. It would be great to have an alternative to flying or driving, but obviously only if it is actually better than flying or driving. The train in question would be both slower, more expensive to operate (if unsubsidized) and less safe by two orders of magnitude than flying, so why would anyone use it?

If we are to make a massive investment in a new transportation system, then the return should by rights be equally massive. Compared to the alternatives, it should ideally be:

SaferFasterLower costMore convenientImmune to weatherSustainably self-poweringResistant to EarthquakesNot disruptive to those along the route

The Hyperloop could meet these criteria, Musk said.

Musk talked about his ambitions for the Hyperloop during a Google-sponsored event with fellow entrepreneur and space explorer Richard Branson last week. "You want the future to be better than the past – or at least I do, quite a bit."

He's known as the real-life Tony Stark: a billionaire inventor working on electric cars, an 800mph 'Hyperloop' train system and reusable rockets. The plan, says Elon Musk, is to minimise climate change – and colonise the red planet