Between building electric cars and sending rockets into space, Elon Musk has plenty to keep him busy. But the tech mogul also wants to reinvent public transportation with the Loop and Hyperloop high-speed transit systems.

On Saturday, he said on Twitter that he plans to test a Tesla and SpaceX-branded Hyperloop pod at half the speed of sound "soon".

The test's objective is to accelerate the pod to around 383 mph (616 km/h) and bring it to a stop within around 3/4 of a mile (1.2 km).

"This is kinda nutty for such a short distance, so could easily end up being shredded metal, but exciting either way," Musk said on Twitter.

In August, the Tesla and SpaceX-branded pod hit a top speed of 220 mph (354 km/h), which was the fastest recorded speed for a Hyperloop pod at the time.

Musk wants to build tunnels for Hyperloop systems

Hyperloop is a high-speed transit system first proposed by Musk in a 2013 white paper. The system would send passengers in pressurised electric pods through vacuum-sealed tubes at over 600 mph (965 km/h).

Musk wants to use his tunnel-digging company, The Boring Company, to create an underground tunnel network that could house Hyperloop and Loop – a lower-speed alternative for shorter distances – systems.

While Musk has faced resistance from city governments and public transit experts, he's received permission to build test tunnels in California and Baltimore, and The Boring Company is one of two finalists to build a new transit system between Chicago's downtown area and O'Hare International Airport.

Musk's biggest competition is Virgin Hyperloop One

But Musk isn't the only one working to develop Hyperloop systems. His most prominent competition is Virgin Hyperloop One, which unveiled a working prototype of a passenger pod, called the Vision 2030 Hyperloop Pod, last week.

The company was hosting Mohammed bin Salman bin Abdulaziz, Saudi Arabia's crown prince and minister of defence, at its test site in the Mojave Desert.

The demonstration was part of a proposal to build a Hyperloop system in Saudi Arabia. Virgin Hyperloop One co-founder and CTO Josh Giegel said such a system would shorten "commute times from hours into minutes", in a press release, which claimed its Hyperloop system would be two to three times faster than traditional high-speed rail, and in some cases, accomplish some trips nearly ten times faster than is currently possible through public transportation.

The company said a trip from Riyadh, Saudi Arabia's capital, to Jeddah, which can last over 10 hours via public transportation, would take 76 minutes with a Hyperloop. And an 8.5-hour trip from Riyadh to Abu Dhabi could be shortened to 48 minutes.

The company hopes to have three Hyperloops running by 2021

Virgin Hyperloop One was founded as Hyperloop Technologies, Inc., in 2014 and conducted its first full-scale test in May.

Richard Branson's Virgin Group announced an investment in the company in October, at which point the company changed its name to Virgin Hyperloop One. In December, the company set a test speed record of 240 mph (386 km/h) at its test site in Nevada.

The company's early ideas for Hyperloop routes have largely been focused in Asia.

Dubai has been discussed as the potential site for one of its first routes, and in 2016, the company began a feasibility study centered on a route between Dubai and Abu Dhabi.

In recent months, the company has also discussed proposals for Hyperloop systems in India and Missouri.

While momentum continues to build around Hyperloop technology, it's unlikely we'll see an operational Hyperloop system in the next few years. On its website, Virgin Hyperloop One says it hopes to have three Hyperloop systems running by 2021.

This article was originally published by Business Insider.

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