A supercavitating submarine creates a bubble of air that encompasses the whole vehicle by ejecting gas through the nose with enough force that it forms water vapor. This greatly reduces drag and allows it to travel at high speeds not possible by standard submarines. (Sources: Defense Update, Popular Science, South China Morning Post. Graphic: Tobey – The Washington Post)

The Chinese Are Reportedly Working On Submarine That Would ‘Fly’ In An ‘Air Bubble’ -- Washington Post

In the annals of vehicular locomotion, the submarine is the equivalent of the Walkman. It dazzled the masses when it hit, flexing nuclear-tipped missiles that completed the so-called “nuclear triad” of deterrence.

But other technologies soon surpassed it in terms of speed and agility. Now, years later, the submarine may be making a comeback — at least theoretically. Researchers at the Harbin Institute of Technology in northeast China tell the South China Morning Post that they’re hard at work on a submarine that the newspaper claims could travel the 6,100 miles from “Shanghai to San Francisco in 100 minutes.”

Read more ....

More News On Reports That The Chinese Navy Is Designing The World's First Supersonic Submarine

Futuristic Chinese ‘supersonic’ sub could reach US shores in under two hours -- RT
China moves closer to developing supersonic submarine: Report -- Times of India
Chinese supersonic submarine with speed up to 3600 mph a step closer to reality -- Tech Times
Chinese submarines could reach US in 'two hours' -- World Bulletin
Chinese Military Claims to Design First Supersonic Submarine -- Breitbart
Rudderless control could bring supersonic submarines from sci-fi to reality -- Defense Update
Supersonic Submarine Can Travel At Unthinkable Speeds! -- Crazy Engineers

My Comment: Designing a supersonic submarine is not the same as actually having one. But it does give an indication on what direction the Chinese Navy is look at.