Project 877/636: Kilo class SSK

Not really.

They don't have two pressure hulls, they have one pressure hull and an outer hull that is flooded and not meant to hold anything out or in.

On the Oscar class SSGNs the gap between the inner pressure hull and the outer hull was where the main Granit missiles were stored... 12 on each side.

The outer hull looks thick but it is sound baffling material.... it is not armour or a pressure hull, it is just the outer skin.

By definition any armour layer that gets penetrated and for the contents of the penetrator to be over 300kgs of HE and the armour actually works against the vehicle by containing the explosion temporarily... intensifying the damage inside and ensuring the entire crew die.

If you want to blow up a tree stump you drill a hole into it and put the charge inside the tree.

If you have to put it outside the tree or object you strap something on the outside for the explosion to push against to damage the thing you are trying to blow a hole through.

For instance to blow a hole through a brick wall you get two flat bits of wood like 4x2s and tape or nail them together in the form of a cross and put plastic explosives at the ends of each of the pieces of wood and put the explosive up against the wall to blow a hole through.

If you were trying to bring down the building with a huge HE charge just open the door and place it in the centre of the building near the structural supports.

Backman wrote:

gc3762 wrote:You do realise the images were fake, propaganda?

Some on the pro Russia side say they are real. Some on the pro Russia side say they are fake.

Close up pics of a submarine like this should never make it on social media either way.

The Russian ministry of defense have unequivocally stated that both vessels will be repaired.  That resolves the question as far as I am concerned.  I can't reconcile the size of the visible damage with the size of the warhead carried by the limey missile.  A internal explosion of that size should have at least distorted the hull from the resulting over pressure yet all we have is a surgical entry hole.

The quality of the pics is also very low which allows the faker to conceal the inevitable artifacts introduced by the shopping work.

Anyway, there is NO one pressure hull WITHIN another, but abreast and on top, as they were constructed to survive a direct hit of US Mk.48 torpedo.

To protect a target from a HE explosion what you need are air pockets. The outer layer of the outer hull carries tiles to reduce noise and the reflection of noise from the outer hull, if they were smart (and they are smart) inside that layer they can have an air pocket and then things like missile tubes or bladders containing ballast water for manouvering and then another air pocket and then the pressure hull if the inner hull.

A blast on the outer hull would crush the outer hull but the air pockets inside would collapse and compress and absorb the blast wave... the way water can't... because water does not compress. In fact the problem is so bad that the US don't use blast HE torpedo warheads any more for their anti sub torpedoes... their anti sub torpedoes for quite some time have been HEAT designs intended t blow a small hole through deep armour to try to reach that inner pressure hull because if they don't reach it they really don't cause substantial damage to the sub despite the rather large weapons they use.