Watertight compartments

[RF]

But even armoured conning towers, by definition, would ducts etc for cabling and communications, which water under high pressure could breach.

[paulcadogan]

You can see the comparative effects of trapped air in sealed compartments versus non-sealed looking at Hood and Bismarck.

Hood sank rapidly and the catastrophic destruction of the aft section meant the forward section sank with compartments sealed for action - the resulting implosion damage ripped off the bow and shredded it, while the mid section was peppered with implosion "punctures". The breakup I would think occured fairly early in the descent since the bow ended up quite far away from the mid section.

In comparison Bismarck filled gradually from below due to the scuttling (and some torpedo damage) - for the scuttling you would think watertight doors and hatches would have been left open - plus she was full of holes topside, allowing water to pour in quickly once below the surface. She therefore would have experienced little implosive damage, hence the relatively intact hull.

A similar comparison would be Titanic's forward and aft sections.

[frontkampfer]

I agree with Paul's comments! All ships break up when they sink. Its a matter of degree based on the circumstances of the sinking.

[RF]

A similar comparison would be Titanic's forward and aft sections.

The stern section suffered extensive damage no doubt made worse by the fact that it was lightly skinned as opposed to being a heavily armoured man oif war.