China developing supersonic submarine powered by a rocket motor.

[Herr Doktor Strangemember]

Exactly. The nuclear missile boats have one job: stay quiet. Even for an attack boat speed is far less important than stealth. They often creep around at far less than their top speed in order to be quieter. Even for special forces missions I can't really see a lot of use for a small high-speed sub that you could hear coming from half way across the world. Maybe I'm just being unimaginative?

For weapons this technology is ideal, since firing any kind of torpedo means making a lot of noise anyway.

For littoral combat I can see the use for inserting/extracting, when your sub transport can move faster than surface forces or ASW air assets can hunt it makes getting from launch point to landing point less nerve wracking and the drive system is not on all the time. Think of it as 'we need to be there now!' or 'get the h377 out of Dodge!' option for the sub.

Modern torpedoes and their launch systems are quiet, less and less is the 'shot' of high pressure air and the sound it makes, swim-out torpedoes that use their own power at low speeds, pistons that quietly push, electric motors etc are all being used. Usually the first sign in a modern sub duel that you've been detected is the sonar of the torpedo on terminal attack. At which point speed is now very important, hence the supercavitating torpedo which might be fast enough to A) Destroy the attacking torpedo; Sink the attacking sub IF you can find it.

Regards.

[Seret]

For littoral combat I can see the use for inserting/extracting

Extracting maybe. I can't see the passengers being totally chuffed about you announcing their arrival to all and sundry. And If you aren't that bothered about making a racket, why not just use an aircraft? The whole point of going subsurface is to be sneaky. I suppose it could be useful if you were going up against an enemy with strong surface and air surveillance but that was particularly lacking in ASW surveillance, but that's pretty niche.

[Idobox]

Extracting maybe. I can't see the passengers being totally chuffed about you announcing their arrival to all and sundry. And If you aren't that bothered about making a racket, why not just use an aircraft? The whole point of going subsurface is to be sneaky. I suppose it could be useful if you were going up against an enemy with strong surface and air surveillance but that was particularly lacking in ASW surveillance, but that's pretty niche.

And if you want to use it for emergency situations, you could always have an evac speedboat inside a submarine.

Moving a submarine at very high speed doesn't make any sense. You can outrun any surface ship without getting supersonic, and you can never outrun a missile or an fighter plane.

The only realistic application is torpedoes.

[Seret]

And if you want to use it for emergency situations, you could always have an evac speedboat inside a submarine.

AIUI that's what what they already do for a lot of insertion/extraction of special forces. They have a RIB in a container on the top deck of the submarine. Saves swimming ashore, which has obvious drawbacks.

[Sky_walker]

Exactly. The nuclear missile boats have one job: stay quiet. Even for an attack boat speed is far less important than stealth. They often creep around at far less than their top speed in order to be quieter. Even for special forces missions I can't really see a lot of use for a small high-speed sub that you could hear coming from half way across the world. Maybe I'm just being unimaginative?

Yea, it looks so.

Who said that this sub can swim only in a supersonic speeds?

It could be used to approach silently, like every other sub, fire, and then escape so quickly that even regular torpedoes wouldn't be able to catch up.

Though it's pure speculation anyway. Come back to me when they'll build a prototype, or at least: a functional scale model.

Edited September 2, 2014 by Sky_walker

[shynung]

There's one threat that a supersonic submarine might not be able to run from: ASROCs, which are basically torpedo-laden missiles. Such a weapon could probably anticipate and take into account the heading and speed of the sub, and intercept it above water, before releasing either Skhval-like torpedoes, depth charges, or even mines ahead of the sub.