China developing a supersonic submarine

[CougarKing]

Mods, please keep this separate from the China superthread.

Source: Washington Post

Chinese reportedly working on submarine that would ‘fly’ in an ‘air bubble’

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.”

That’s not in the cards. But there’s plenty of reason to believe a submarine could be built that would significantly exceed the speed of today’s fastest models, which lumber along at a speed of 40 knots (about 46 mph.) It all has to do with friction and how to conquer it.

The reported plans for the super-fast Chinese submarine draw on research that reaches back to the Cold War on “supercavitation,” a technology that creates a friction-less air “bubble” around a vessel that allows it to “fly” underwater, facilitating incredible speeds. The Russians have developed torpedoes that travel faster than 230 mph using that approach.

(.........SNIPPED)

The potential of supercavitation has not gone unnoticed by the U.S. Navy. “Some technologies innovations have so significant an impact on our way of doing business that they are often described as ‘disruptive technologies,’ with the potential to change the future,” said a 2002 paper published in Undersea Warfare, the official publication of the submarine force. One of them, it said, was “‘supercavitation’ techniques.”

The Defense Advanced Research Projects Agency was once reported to be doing much the same, and Popular Science says the project would have allowed the “delivery of men and material faster than ever.” That’s exactly the end game for the Chinese research team: civilian transportation — or even swimming.

“If a swimsuit can create and hold many tiny bubbles in water, it can significantly reduce the water drag,” Li explained. “Swimming in water could be as effortless as flying in the sky.”

Still, questions remain. Wang Guoyu, who leads the Fluid Mechanics Laboratory at Beijing Institute of Technology, expressed doubt at its success. “The size of the bubble is difficult to control, and the vessel is almost impossible to steer,” he told the South China Morning Post, adding that if any part of the ship breaches the bubble, it would snap off due to the density difference.

 

[c_canuk]

if they can't do it silently, then there is no point.

Surface vessels can already go extremely fast noisily. The Submarine's advantage is that it can sneak into an area undetected on passive sonar. Slamming though self created cavitation is going to be rather less than stealthy.

 

[Kilo_302]

This is true, but it would be useful for fast transits. While it looks like the Chinese are mainly focused on operations in the littorals, having the ability to get subs into place thousands of miles away in a fraction of the time couldn't be a bad thing. They could just reduce to cruising speed once they're in their AO.

 

[Colin Parkinson]

or evade ASW assets once they completed an attack.

 

[Kirkhill]

What's wrong with the Thunderbird 2 solution for fast transit?

Replace Thunderbird 2 with a C-17.
Replace Thunderbird 4 with a suitably sized Midget Sub, a bunch of Autonomous Undersea Vehicles and some CAPTOR mines and you are away to the races.

Of course the Navy might want a Big Honking Mother of a Ship for recovery operations..... >

 

[daftandbarmy]

How We Can Get Submarines to Travel at Supersonic Speed

Chinese researchers say they are developing technology that would allow submarines to travel more than 750 mph. That’s faster than commercial aircraft fly, and yes, it is possible.

The technology is called supercavitation, and it’s been around for decades. The idea is to increase the speed of an object like, say, a submarine or torpedo by creating a bubble around it, reducing drag as it moves through the water. The nose of the vehicle typically is designed to create the bubble, and gas often is used to shape the bubble. The Soviets used this trick on the Shkval torpedo in the 1960s and ’70s; it was capable of 230 mph but for no more than a few miles.

http://www.wired.com/2014/08/how-we-can-get-submarines-to-travel-at-supersonic-speed/

 

[a_majoor]

Best way to counter this is not to be in the water at all. In the 1950's the Glen Martin company created a B-52 sized jet seaplane (P6M SeaMaster) which would have provided a means to rapidly deploy around the globe, and be able to bring a huge bucket load of sensors, mines, torpedoes or anti ship missiles (as well as nuclear weapons).

As Kirkhill pointed out, there is no reason a modernized version could not also land and deliver SEALS or midget submarines, UUV's and so on. This would be an extreme version of "Sprint and Drift" tactics (flying around would be the "sprinting", while landing and deploying/retreiving sensors or other items would be the "drifting".

And while a Seamaster might be expensive, it certainly would not cost as much as a frigate, SSN or aircraft carrier. Having a wing of seaplanes to supplement surface warships would make for an interesting mix of capabilities.

 

[Colin Parkinson]

How We Can Get Submarines to Travel at Supersonic Speed

Chinese researchers say they are developing technology that would allow submarines to travel more than 750 mph. That’s faster than commercial aircraft fly, and yes, it is possible.

The technology is called supercavitation, and it’s been around for decades. The idea is to increase the speed of an object like, say, a submarine or torpedo by creating a bubble around it, reducing drag as it moves through the water. The nose of the vehicle typically is designed to create the bubble, and gas often is used to shape the bubble. The Soviets used this trick on the Shkval torpedo in the 1960s and ’70s; it was capable of 230 mph but for no more than a few miles.



http://www.wired.com/2014/08/how-we-can-get-submarines-to-travel-at-supersonic-speed/

Now just imagine your navigational calculations are off by just .5 of a degree, traveling in the bubble across the ocean you will have no sensors and going by Dead Reckoning. I imagine them saying: "We should just be passing Midway right abou......."

 

[a_majoor]

In the equipment thread I posted about two very long duration, low energy, slow and essentially silent types of platforms which could be deployed to provide sensor coverage to wide areas (or dumped in a limited AO to provide saturation coverage). Look up Sea Glider and Wave Glider to see how these essentially engineless ships work. Expanded view of a Wave Glider platform attached)

A screen of these patrolling in the Western Pacific will be able to provide much more coverage and warning about any sort of submarines or other naval activity in the area.