A sleek prototype of a high-speed train unveiled recently in China is designed to carry passengers at a speed of 600 kilometers per hour, or 370 mph. That’s more than 150 mph faster than the world's fastest passenger trains now in regular intercity service, which touch 217 mph on runs between Beijing and Shanghai.

The new train, under development by the state-owned China Railway Rolling Stock Corporation (CRCC), is designed not to run on rails but to float above the track using a technology known as magnetic levitation, or maglev.

Given the train’s tremendous speed, a trip by train could be even faster than traveling by air under certain circumstances, Ding Sansan, the head of the team developing the new train, told the Chinese newspaper Qingdao Daily. He said a trip from Beijing to Shanghai that might take four and a half hours by plane could be completed in about three and a half hours by the new maglev train.

Some media outlets reported that the train would begin service in 2021, but the company didn’t give an exact date — and rail experts say years of testing will be required before the train is ready to carry passengers.

Interior view of a maglev train developed by the state-owned China Railway Rolling Stock Corporation. Zhang jinggang / Imaginechina via AP file

“The Chinese maglev is very much a research project at this stage,” Chris Jackson, editor-in-chief of London-based Railway Gazette International, said. “There are no firm plans to develop a commercial route.”

Maglev train technology has been in development for decades. It uses powerful electromagnets to levitate train cars just above the track and provide forward propulsion, eliminating the friction from the metal wheels used by conventional trains.

In addition to being faster than conventional trains, maglev trains produce less noise and vibration, a boon for people living or working near the tracks, as well as for passengers and crew aboard the trains. Maglev trains also have fewer parts and thus promise greater reliability.

The new Chinese train won’t be the world’s first maglev train. Since 2002, a maglev demonstration train has been carrying passengers at speeds of up to 267 miles per hour on 19-mile runs between the outskirts of Shanghai and the city’s main international airport.

Japan is working on a maglev train that could begin service between Tokyo and Nagoya in 2027, carrying passengers at about 370 mph — the same speed projected for China’s new train.

A 300-mph maglev train has been proposed between Washington, D.C., and Baltimore, but Larry Blow, a maglev consultant in Arlington, Virginia, said the high cost of building it — estimated at $10 billion to $12 billion — is likely to scuttle that project.

But Blow said maglev trains could still find a place in the United States for urban transit systems, over short distances and at moderate speeds — perhaps around 60 mph. "That would be the much more popular application, if only for cost reasons," he said.

The fastest passenger train currently in regular intercity service in the United States is Amtrak’s Acela Express, which reaches a top speed of 150 mph on runs between Boston and Washington, D.C. — but only for 34 miles of the 450-mile route.

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