The once-mighty submarine, which, a while ago, was passed by new technologies in speed and agility, may be streaming its way back to transport relevance with a new "air bubble" technique created by the Chinese.

Researchers at the Harbin Institute of Technology in northeast China have told the South China Morning Post they're designing a new-age submarine that, according to the newspaper, could sometime in the future be able to course through the water from "Shanghai to San Francisco in 100 minutes," reports the Washington Post.

Such a feat would require a sub to far exceed the speed of today's fastest underwater ship, which are only able to reach speeds up to about 40 knots, or 46 miles per hour.

The apparent plans for the much-faster Chinese sub would be based on so-called "supercavitation" research that was first investigated during the Cold War.

The approach employs a friction-less air bubble around a vessel that gives it the ability to move much more swiftly through water.

The Russians have used the same technique to build torpedoes capable of traveling faster than 230 mph, the Washington Post report said.

"We are very excited by its potential," lead researcher Li Fengchen, a professor of fluid machinery and engineering with the Harbin Complex Flow and Heat Transfer Lab, told the South China Morning Post. "Our method is different from any other approach."

Li explained in the Morning Post story that a vessel would essentially travel within a liquid membrane created by releases gases from the sub's nose.

"By combining liquid-membrane technology with supercavitation, we can significantly reduce the launch challenges and make cruising easier," he said, adding that increasing or decreasing the liquid membrane around the sub would manipulate friction to steer the ship.

Although added specifics about the research are being guarded by the Chinese government, Morning Post reporter Stephen Chen told the Washington Post through an email that "these studies in China do not go to academic papers, but the technology is being tested in the laboratory ... the scientists have received pressure from authorities due to the sensitivity of the research and they hope the matter can cool down a bit."

The Chinese aren't the first to think about applying such mechanics to a passenger vessel.

The Defense Advanced Research Projects Agency (DARPA) was at one point pursuing a similar water craft that Popular Science says would have allowed the "delivery of men and material faster than ever."