Hit on Bismarck's turret

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Re: Hit on Bismarck's turret

Post by Bill Jurens » Fri May 24, 2019 7:05 pm

@ Alexandros:

You will note that I was not specific about the source of the initiation of the deflagration, if that's what was indeed observed. There are actually quite a few well-documented instances where turrets and barbettes were penetrated with subsequent burnouts and/or explosions etc.

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Re: Hit on Bismarck's turret

Post by alecsandros » Fri May 24, 2019 8:08 pm

Bill Jurens wrote:
Fri May 24, 2019 7:05 pm
@ Alexandros:

You will note that I was not specific about the source of the initiation of the deflagration, if that's what was indeed observed. There are actually quite a few well-documented instances where turrets and barbettes were penetrated with subsequent burnouts and/or explosions etc.

Bill Jurens
It's greek , therefore 'Alecsandros'

If either turret / barbette was perforated and some internal deflagration occured,
that turret would have been completely destroyed.

Therefore it couldn't have been observed , later , either firing one more salvo (case of turret Anton)*, or seen with guns elevated high in the air, and later still to be demolished by a 3000m-distant heavy shot from HMS Rodney (case of turret Bruno - which apparently received a direct perforating hit , that blew it's back off. Difficult as such a report is to be taken at face value, it still offers a ballpark figure for the time of destruction of turret Bruno. Because, if time of destruction is 9:40, it can not be 9:02 as well).

Finally, any perforation with deflagration at 9:02, causing destruction of one main turret, would have been mentioned by at least one survivor . I can't find any...

I'm curious over the documented instances that you mention. Any examples of heavy artillery shot during WW2 ?

*[there is also at least one source mentioning both forward turrets firing at 9:27... further indicating none of them was destroyed by fire at 9:02]

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Re: Hit on Bismarck's turret

Post by Bill Jurens » Fri May 24, 2019 10:24 pm

@ Alecandros:

My apologies about getting your name wrong.

The main problem lies, I think, in attempting to assemble a coherent and accurate reconstruction from the evidence available, which is, as we all know somewhat fragmentary and contradictory. It's my recollection that many accounts seem to suggest that Anton and Bruno were taken out of action quite early in the fight by a single round, and others -- one of which you noted -- suggesting that the turrets were operating some time later.


It's just my impression that any spectacular burst of flame observed is more likely to be via the combustion of propellant (or somewhat less likely due to the burning of some other flammable liquid or gas). There are relatively few instances -- perhaps none -- where direct observations of the explosion of armor-piercing type rounds seem to have created other than a momentary bright flash. The descriptions seem to describe something more lasting, like some sort of fireball. What might have caused that fireball, other than propellant, is difficult to say, but I don't think it was from an exploding projectile. It might have been flame coming up nearly vertically from a loading hatch...

I don't know why you feel that a perforating hit on a turret or barbette that blew the back off the turret seems implausible. My observation of the Bismarck wreck -- very up close and personal -- suggests that an internal explosion in turret Bruno caused an overpressure failure of the deck in the overhang area and that the back, rather than being blown out backwards, but no longer properly supported from below, simply fell down nearly vertically and landed on the deck below, before being lost overboard as the ship sank.

I have a recollection, some notes, and a sketch showing what is quite likely the back plate of Bruno here in my files, made during one of the research dives. It seems to show the penetration of a large caliber projectile travelling almost horizontally on a rather oblique path, probably going from inside to out. What that means, or might mean, is hard to say -- it might not even be the back plate of Bruno at all, as it's often very difficult to interpret these things when scale is uncertain, lighting is bad, things are half (or more) buried in the mud, and there is always pressure to move on to other things...

You are correct in observing that the majority of gunfire-induced main battery turret burnouts and explosions seem to have taken place during World War I. This is, I suspect, mostly because WWI simply involved many more ship-to-ship main battery gunnery engagements. Although the British certainly seemed to feel that some additional modifications to propellant handling were necessary -- and made some of them -- so far as I know, the Germans seemed to be quite happy -- considering the circumstances involved -- in how their turrets behaved, and didn't make many changes at all, so WWI experience can be more accurately extrapolated to WWII experience. I guess...

The Bismarck turrets have all been located on the bottom. As I recall, all are upside down, as might be expected, and it's possible in a few cases to examine a fair amount of the rotating structure in detail. Although some additional examination might be able to yield a few more clues, e.g. are the hoist still holding projectiles to be fired, etc., and what might have been the training azimuth when the turret slid free, it's unlikely that these relatively minor clues would yield much more of value in trying to reconstruct in any meaningful detail what exactly happened on 27 May. The condition of the wreckage, the location of the wreckage, and the passage of time have, I think, more or less rendered anything resembling a detailed reconstruction impossible...

Bill Jurens

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Re: Hit on Bismarck's turret

Post by alecsandros » Sat May 25, 2019 6:30 am

You're thinking that the report about Bruno's back being blown off was somehow mis-remembered, as a time interval, and actually took place at 9:02 ?

I don't think it would be impossible, especially as I have been told that ranges at 9:02 were around 16-17km, thus anything could happen.

I remain reserved however.

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Re: Hit on Bismarck's turret

Post by Bill Jurens » Sat May 25, 2019 3:43 pm

The physical evidence regarding the time at which Bruno's back plate(s) may have been detached is silent. There is none. It might be possible to infer via the position of damage to the deck below approximately on what bearing the turret was trained when the plates fell off the back, if that's indeed what happened. My recollection of this is that the turret would have been trained at approximately 30-45 degrees to starboard of the centerline when the incident occurred. From this one might be able to infer at approximately what times Bismarck might have been engaging on that bearing, but such an exercise could only be highly speculative at best.

If the hole in the backing plate has been correctly identified, and assuming that's what initiated the explosion, that suggests that the attacking projectile probably entered on the starboard side of Bruno's gunhouse somewhere around the overhang. But again, this can only represent the most tentative speculation. A (barely) educated guess...

I would, overall, not put much credence on detailed visual accounts unless they can be verified via other unrelated observers. Testis unis, testis nullis...

Bill Jurens

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