HMS Hood & USS Arizona Magazine Explosions

[Djoser]

Another link showing a drawing of the Oklahoma at rest nearly upside down.

http://www.ussoklahomabb37.ussindianabb ... ma105c.jpg

Obviously the mud of the 40 foot harbor bottom could have kept the turrets from falling out completely,even if they weren't held in place somehow. But I suspect that if the turrets were 'loose' (held in place by weight) as in Hood and Bismarck, that they would have slid out at least somewhat, and when righted there would have been some displacement noted.

It would be interesting to read the literature concerning the salvage, and find out about the turrets.

[paulcadogan]

But Djoser, on Hood the turret structure (forward) didn't fall out - despite even the implosions that broke up her hull forward of the turrets. For A-turret - which is visible on the wreck, the gun house and guns broke away, leaving the floor in place - so the rest of the structure down to the magazines still must be in place.

http://www.hmshood.com/hoodtoday/2001ex ... /index.htm

Also, Prince of Wales and Repulse also rolled over as they sank - PoW being completely, Repulse partially inverted on the sea floor, but their turrets are in place.

So the turrets falling out is not a given - and did not occur in any of the 3 British ships.

[Djoser]

Aha wow didn't know that--thanks for posting...

[paulcadogan]

Royal Oak too!



But question....Tirpitz rolled over, but did her turrets dislodge? Or did she not roll enough?

[Thorsten Wahl]

Another possibility might be if the firing was being done through the automatic stabilized firing circuits rather than having the layer fire the guns based upon his judgement of the timing of the roll. In this instance, the layer presses his firing key but the guns do not fire until the gunnery gyro closes the firing circuit when the mounts are level. Depending on how much the ship is pitching and rolling, there might be a very slight delay between the firing of the forward and after turret groups making it appear to be two separate salvos instead of a broadside. British witness did note the apparent ripple fire effect on both German ships, and this might well have been because the Germans were using the stabilized firing devices.

the rippleeffects was depending on the firing procedure.

The main guns didnt fire by pressing a button. The guns = turrets were not trained continously on the aiming angle of the calculated firing solution. They were in a standby position near the aiming angle. At the firing the turrets were moved through the aiming angle and the firing was automatically triggered when train angle of the guns and aiming angle of the firing solution were identical (minus a small angle for correction caused by the delay between closing the electric firing contacts until the projectile leaves the muzzle(innerer Verzug).

As the standby angles wer not identical, the drive through the firing solution requires different time as the firing off the turrets were indivdually triggered.

[Djoser]

Royal Oak too!



But question....Tirpitz rolled over, but did her turrets dislodge? Or did she not roll enough?

Thanks for posting that recreation.

I'm not sure about the Tirpitz--but I do seem to recall reading that the one turret (Caesar?) was propelled out of its barbette when that magazine exploded under it. Can anyone conform this?

[Dave Saxton]

Yes, that is correct.

[Djoser]

Thanks Dave. Oh and I meant 'confirm'. Once again posting after a night at work haha! I don't drink at work (unlike most DJs I know) but I get very spacey from being tired, but then I cannot sleep.

[Djoser]

Royal Oak too!

I wonder what that long rent in the hull plating is from? Some kind of shockwave/stress effect from the 4 torpedoes hitting on the other side?

Also, I remember reading in the book I have about the sinking (I believe it is called 'The Royal Oak Disaster' but I could be wrong, it's not right here now), that one of the survivors reported seeing one of the 15" gun barrels actually bending due to the stress or heat or whatever. I don't believe it, nor do I believe that one of the Queen Mary's Q turret guns bent as was reported by a survivor. Not that I would ever call those brave men liars to their faces--I am more inclined to think it was an optical illusion of some kind, or the effect of the stress of the situation on their vision somehow. Anyone have any ideas about this? I realize it's slightly off-topic, sorry.

[paulcadogan]

I wonder what that long rent in the hull plating is from? Some kind of shockwave/stress effect from the 4 torpedoes hitting on the other side?

I really can't answer that with any certainty - I'd suspect it might be a crumpling effect of the impact with the sea floor - especially given that it's over the bulge?? I know there are others here with far greater knowledge of stuff like this!

Here's a link to the video from which the image was taken:

http://www.youtube.com/watch?v=vWaMn9XGzoU

And a more detailed description of the wreck (by a diver) is here:

http://www.divemagazine.co.uk/uk-diving ... -royal-oak

Seems her turret roofs fell off.

[Djoser]

Thanks Paul!

[steffen19k]

Here's another interesting magazine explosion: HMS Barham.

She was torpedoed, & in her sinking her magazines exploded. It's been attributed to her 4 in AA ammunition touching off the 15 inch magazines. It would seem 4 inch ammo The video of the explosion is quite clearly caught on film, and the Inquiry into Barham's loss indicated 4" ammo was stowed in the wing passages around the 15 inch magazines to facilitate greater ammunition capacity.

http://en.wikipedia.org/wiki/HMS_Barham_(04)#Aftermath

[paul.mercer]

Gentlemen,
A couple of questions, on any warship, particulary large one like Battleships, when were the fuzes actually put in to the shell - was it only just before action was expected? Also what was the situation after action had finished were any shells that had been loaded into the breeches simply fired off or were they unloaded and the fuzes removed before returning to the shell room ?

[Steve Crandell]

Gentlemen,
A couple of questions, on any warship, particulary large one like Battleships, when were the fuzes actually put in to the shell - was it only just before action was expected? Also what was the situation after action had finished were any shells that had been loaded into the breeches simply fired off or were they unloaded and the fuzes removed before returning to the shell room ?

It was difficult to unload a gun because the ramming process seated the shell pretty solidly. They were usually unloaded "through the muzzle" by firing the guns.

Fuses were usually installed in the shell when manufactured. They weren't activated until the shell was fired. The explosion of shells on board was due to heat build up from fires causing spontaneous detonation of the shell's explosive filler. That was not normally the cause of a magazine explosion, though. That was usually due to the explosion of propellant, not shells. Propellant was a lot more unstable than shells; especially Cordite, which I believe was only used on British ships.

Arizona was destroyed when the black powder charges for her catapults exploded and blew up the ship's forward magazine. It's use was soon discontinued for that reason.

[paul.mercer]

Gentlemen,
A couple of questions, on any warship, particulary large one like Battleships, when were the fuzes actually put in to the shell - was it only just before action was expected? Also what was the situation after action had finished were any shells that had been loaded into the breeches simply fired off or were they unloaded and the fuzes removed before returning to the shell room ?

It was difficult to unload a gun because the ramming process seated the shell pretty solidly. They were usually unloaded "through the muzzle" by firing the guns.

Fuses were usually installed in the shell when manufactured. They weren't activated until the shell was fired. The explosion of shells on board was due to heat build up from fires causing spontaneous detonation of the shell's explosive filler. That was not normally the cause of a magazine explosion, though. That was usually due to the explosion of propellant, not shells. Propellant was a lot more unstable than shells; especially Cordite, which I believe was only used on British ships.

Arizona was destroyed when the black powder charges for her catapults exploded and blew up the ship's forward magazine. It's use was soon discontinued for that reason.

Thanks for that Steve,
I read somewhere that Tirpitz was using her 15" fuzed to explode in the air, does that mean she would have had a mixture of AP, SAP and airburst shells
on board?