Hood explosion

[paul mercer]

Just a thought, but I think there was some controversy as to whether both Hoods magazines blew up.
Am I right in thinking that some ships had passageways running right through the bottom of the ship to enable shells & cordite to be moved from one magazine to another. If so, could the flash from one magazine have travelled from the bow to the stern magazine (or from stern to bow), the force of the explosion blowing off any doors that were in the way. It would seem from the underwater film that Hood appears to be in three major pieces, so could that be the reason?

[Antonio Bonomi]

Ciao Paul and all,

I leave the field on this response to more experts guys than me, .. hoping that Bill Jurens for example can answer to your question.

My 2 penny here is just this shoking video were you can see HMS Barham sinking and exploding after.

Well, I think this explosion is in some way is comparable to what happend to HMS Hood,.... a cordite deflagration very fast enveloping entirely the ship and maybe causing other chain effects,.. I do not know.

But just this one I think is enough,.... to explain,..how they described Hood was enveloped by smoke after the explosion from bow to stern, .. and soon after making high pillars of black smoke ( as we can see on available photo sequences and paintures ).

Here you can have a clear close reference, .... and it is really impressive .....

http://www.youtube.com/watch?v=C06w7tS7p-Q

Ciao Antonio

[marcelo_malara]

I was looking in the AOTS volume but can´t find a passage between the forward magazines and the after ones. The only ammo passage is located on the main deck, that is the armored deck, and I think it was used to transport shells to the secondary guns.

[tommy303]

In my opinion it is highly doubtful that the explosion of the after magazine group caused a similar explosion of the forward group. There were ammunition alleyways that led from the after 4-inch magazine lobby on the armour deck forward to the hoist along the shelter deck and to the forward lobby, but the doors were kept closed until resupplying the 4-in RU lockers was required. Even then, 4in rounds had to be sent up to the lobbies by hoists from lower quarters below the armour deck. Consequently there was no direct connection between the forward and after magazine groups.

One did not see that happen with the Arizona when her forward magazines blew: the after magazines and turrets remained intact. I believe the rapidity with which Hood sank had more to do with the state of the wreck on the bottom. Vessels which sink in such short times, rather than filling up slowly, tend to suffer considerable breaking up. A good example are the two main sections of the Titanic. The forward section is relatively intact, having flooded out. When the ship split in half near the the engine rooms, the flooded bow section headed to the bottom, but the stern which was still bouyant bobbed about and then sank quickly, much like the fore section of the Hood. The stern section of the liner suffered enormous damage in sinking so quickly with sections of the deck and side plating ripped away or peeled back.

[Tiornu]

As far as I can tell, the theory of the forward magazine explosion is nonsense. There is an area of damage forward, but it isn't even centered on the magazine--so where's the evidence? There isn't any.

[Bill Jurens]

There was no forward magazine explosion on Hood. The forward hull failure was due to hydrostatic implosion.

Bill Jurens.

[paul mercer]

Thanks for your replies chaps.
I'm surprised that Hood suffered from implosion as she would have been much more heavily constructed than 'Titanic' and isn't as deep.
As for the passageways, from what you say there was not any method of transfering shells from one end of the ship to the other, except by hoising them out the same way they went in. This also seems surprising, given that in a long stern chase a ship might well be only using it's forward guns, causing a shortage in the forward magazines.
Anyway, thanks again.

[marcelo_malara]

Be aware that the water pressure is 1 bar (or 1kg/cm2) for every ten metres. So a ship sunk at 2000 mt will receive a pressure of 200 bars (or 200 kg/cm2). A plate 1 m2 will receive a weight of 2000 tons. Only a structure designed for the deep will resist it.

[paul mercer]

Be aware that the water pressure is 1 bar (or 1kg/cm2) for every ten metres. So a ship sunk at 2000 mt will receive a pressure of 200 bars (or 200 kg/cm2). A plate 1 m2 will receive a weight of 2000 tons. Only a structure designed for the deep will resist it.

Wow, that a lot of pressure, it's not so surprising then!
Thanks for the info.

[Bgile]

Thanks for your replies chaps.
I'm surprised that Hood suffered from implosion as she would have been much more heavily constructed than 'Titanic' and isn't as deep.
As for the passageways, from what you say there was not any method of transfering shells from one end of the ship to the other, except by hoising them out the same way they went in. This also seems surprising, given that in a long stern chase a ship might well be only using it's forward guns, causing a shortage in the forward magazines.
Anyway, thanks again.

US Battleships had a provision for transferring main battery ammunition within the citadel from one end to the other on an overhead track, but I doubt it would be practical during battle. For one thing, I think the shell ring would have to be rotated to the place where the incoming projectile was to go, and this would interfere with the loading cycle. Of course a big consideration was that numerous doors would have to be opened to allow the shell to be moved and that would compromise DC integrity. Finally, this process would be many times slower than a normal loading cycle.

[Tiornu]

I doubt that implosion makes any great distinction between merchant ships and men o' war. Hood would be a prime candidate for implosion because she went down so quickly, in contrast to a ship like Bismarck that had been slowly filling with water for some hours. Hood's implosion damage probably took place not far below the surface. I'm not sure why I'm bothering to comment as we have Bill who can address this with authority.