Hits on PoW and Bismarck

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paul.mercer
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Hits on PoW and Bismarck

Post by paul.mercer » Sat Oct 06, 2018 9:53 pm

Gentlemen,
When PoW was drydocked they found an unexploded 15" somewhere near her keel and during the battle PoW put two hits through Bismarck's bow but neither exploded, had all three shells gone off would that have made any difference to the outcome?

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Alberto Virtuani
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Re: hits on PoW and Bismarck

Post by Alberto Virtuani » Sun Oct 07, 2018 7:41 am

Hi Paul,
re. the Bismarck hit (n.5 in the PoW damage report) it's extremely difficult that a shell travelling underwater for a long way like the one you mention can explode anyway. A "good" shell should be activated by the water impact first and should explode before reaching the ship, in this case. I imagine that the shell was a "dud" anyway.

Had it exploded inside the ship, it would have had serious consequences, exploding in (or close to) a diesel generator room inside the vitals of the ship, causing flooding in the machinery as well, possibly similar to the underwater one that did explode on Bismarck, or worse.


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

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Re: hits on PoW and Bismarck

Post by paul.mercer » Sun Oct 07, 2018 9:46 am

Thanks Alberto,
What about the one that lodged around PoW's keel, would that have broken it in half or would the double bottom prevent this?

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Alberto Virtuani
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Re: hits on PoW and Bismarck

Post by Alberto Virtuani » Sun Oct 07, 2018 10:08 am

Hi Paul,
I think we are speaking of the same single 15" hit (in the PoW damage report it is numbered #5, the diesel generator room is underlined by me in red).

It traveled underwater for a long distance (estimated 80 feets!) before reaching the PoW very close to her bottom, entered the ship piercing a number of thin steel plates, and rested without exploding against the torpedo bulkhead, very close to the bottom of the ship, without piercing it because its velocity had been extremely reduced by the water and the ship's plates.

Hit_N5.jpg
Hit_N5.jpg (51.72 KiB) Viewed 863 times

I absolutely don't believe that a single shell can break the ship in two.
HMS Warspite keel resisted to a "Fritz" bomb penetrating all armored decks and exploding close to the bottom in a boiler room without breaking in two and the explosive charge of a 15" shell is extremely smaller than the charge of the "Fritz".


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

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Re: hits on PoW and Bismarck

Post by alecsandros » Sun Oct 07, 2018 10:49 am

Alberto Virtuani wrote:
Sun Oct 07, 2018 10:08 am
HMS Warspite keel resisted to a "Fritz" bomb penetrating all armored decks and exploding close to the bottom in a boiler room without breaking in two and the explosive charge of a 15" shell is extremely smaller than the charge of the "Fritz".
We should not forget that Hood was destroyed by a single 15" shell - striking the powder magazines. If such a hit could be obtained on Prince of Wales as well... The ship would probably be lost as well. The different thing about the 2 battleships was that it was much , MUCH more difficult to "put" a 15" shell inside Prince of WAles magazines then it was to put it in Hood's magazines...

As for Fritz X , the bomb managed to sink RM "Roma" in 1943. There were several direct hits, but the one that struck the forward main magazins would have been probably enough. The ship exploded and sank in short order after receiving that hit...

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Re: hits on PoW and Bismarck

Post by Alberto Virtuani » Sun Oct 07, 2018 11:02 am

Hi Alec,
agree, in case a shell (or a bomb) explodes igniting a main magazine the "quantity of explosive" is surely enough to sink the ship and possibly to break her back as well.
In the PoW case, there was no main magazine close to the path of this 15", as well as in Warspite case with the "Fritz", thus I don't believe the ship would have been crippled even by the possible explosion of the shell against the torpedo bulkhead.


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

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Re: hits on PoW and Bismarck

Post by wadinga » Sun Oct 07, 2018 8:00 pm

Hello Alberto,

Are you the same Alberto who is withholding the so-called Silver Bullet and an apparently secret letter from Jasper to Raeder, but now supplying Free of Charge an unpublished diagram of the hit on PoW?

Fascinating. :cool:

All the best

wadinga
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Alberto Virtuani
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Re: hits on PoW and Bismarck

Post by Alberto Virtuani » Mon Oct 08, 2018 6:54 am

Another free provocation form a loser in his last "crusade" (http://www.kbismarck.org/forum/viewtopi ... 930#p80758)......


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

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Re: hits on PoW and Bismarck

Post by paul.mercer » Mon Oct 08, 2018 8:20 pm

Alberto Virtuani wrote:
Sun Oct 07, 2018 10:08 am
Hi Paul,
I think we are speaking of the same single 15" hit (in the PoW damage report it is numbered #5, the diesel generator room is underlined by me in red).

It traveled underwater for a long distance (estimated 80 feets!) before reaching the PoW very close to her bottom, entered the ship piercing a number of thin steel plates, and rested without exploding against the torpedo bulkhead, very close to the bottom of the ship, without piercing it because its velocity had been extremely reduced by the water and the ship's plates.


Hit_N5.jpg


I absolutely don't believe that a single shell can break the ship in two.
HMS Warspite keel resisted to a "Fritz" bomb penetrating all armored decks and exploding close to the bottom in a boiler room without breaking in two and the explosive charge of a 15" shell is extremely smaller than the charge of the "Fritz".


Bye, Alberto
Thanks again Alberto, I did think you were referring to the hits on Bismarck! However, I believe that PoW's hits on Bismarck went straight through her bow without exploding and still caused considerable damage, had they gone off do you think that the damage to her fuel etc could have been catastrophic and enough to take her out of the battle?

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Re: hits on PoW and Bismarck

Post by Bill Jurens » Mon Oct 08, 2018 8:35 pm

Bismarck was hit only once in the bow, not twice. The best evidence would suggest that if projectile in question detonated at all, it did so on or slightly outboard of the shell plating on the disengaged side. Whether the projectile exploded or not would not likely have led to any significant difference to subsequent activities, except that if the hole in the shell were very large, as might have occurred if the projectile detonated inside the ship, it might have required Bismarck to reduce speed somewhat during the rest of the operation. Detonation, or lack thereof, would have likely made no significant change to the fuel situation either way.

The practical effects of a slightly slower Bismarck lie purely in the realm of speculation.

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Re: hits on PoW and Bismarck

Post by paul.mercer » Mon Oct 08, 2018 8:38 pm

Bill Jurens wrote:
Mon Oct 08, 2018 8:35 pm
Bismarck was hit only once in the bow, not twice. The best evidence would suggest that if projectile in question detonated at all, it did so on or slightly outboard of the shell plating on the disengaged side. Whether the projectile exploded or not would not likely have led to any significant difference to subsequent activities, except that if the hole in the shell were very large, as might have occurred if the projectile detonated inside the ship, it might have required Bismarck to reduce speed somewhat during the rest of the operation. Detonation, or lack thereof, would have likely made no significant change to the fuel situation either way.

The practical effects of a slightly slower Bismarck lie purely in the realm of speculation.

Bill Jurens
Thanks very much for that info Bill

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Re: hits on PoW and Bismarck

Post by Alberto Virtuani » Mon Oct 08, 2018 8:46 pm

Bill Jurens wrote: "The best evidence would suggest that if projectile in question detonated at all, it did so on or slightly outboard of the shell plating on the disengaged side"
Hi Mr.Jurens,
I think I remember that the Baron speaks about the dynamic pressure of the water against a fore transversal bulkhead when Bismarck was speeding, forcing the crew to reinforce the bulkhead. Doesn't this point to an explosion tearing a quite large hole (larger than around 14") in the hull at least at the exit point ?


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

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Re: hits on PoW and Bismarck

Post by Bill Jurens » Mon Oct 08, 2018 11:41 pm

Alberto wrote:

I think I remember that the Baron speaks about the dynamic pressure of the water against a fore transversal bulkhead when Bismarck was speeding, forcing the crew to reinforce the bulkhead. Doesn't this point to an explosion tearing a quite large hole (larger than around 14") in the hull at least at the exit point ?"

Unfortunately, except in unusual circumstances, there is no reliable correlation between pressures inside the shell and pressures outside the shell when the vessel is in fairly rapid motion. These sorts of things are often somewhat counter-intuitive. Actually, in some cases the pressure outside the shell is LOWER than the pressure inside, resulting in a suction pulling water out of the hole instead of allowing it in.

To illustrate this effect, planing craft and other small boats are often equipped with a small drain plug near the keel. If the boat were stationary, e.g. tied up at a pier, the removal of the plug would sink the boat, but when removed at speed, this sort of drain plug actually sucks the bilge water out.

In any case, I doubt if the Baron had sufficient technical knowledge to comment on this sort of issue reliably. He may have known that bulkheads were being reinforced, and concluded by default -- as may would -- that this was to attempt to counteract dynamic pressure effects. This may not have been true at all. Further, in most works in English, one is actually reading a translation, where subtle technical nuances are often lost to the translator, who is not usually adept at the translation of highly technical jargon. The same, of course, applies to translation into other languages as well. So, in brief, the Baron may not have really even known what he was talking about in German...

The Baron was a fascinating fellow, and resided for many years in Toronto, Canada, as a career diplomat. (During that time, I corresponded with him a bit regarding the accuracy of Bismarck's gunfire.) In that role, he was very careful about his language, and the possible consequences thereof. He would never tell a lie outright -- dead honest in that regard -- but was very good at telling only that part of the truth which was diplomatically advantageous and sufficient to answer the question. It was only a fair bit afterwards that I discovered how carefully nuanced some of his statements were. Diplomatic conversation -- telling 'just enough' -- is an art, and he was very good at it.

Bill Jurens

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Alberto Virtuani
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Re: hits on PoW and Bismarck

Post by Alberto Virtuani » Tue Oct 09, 2018 7:36 am

@Bill Jurens,

Hi Mr.Jurens,
thanks for the clear explanation.

Re.the Baron "diplomatic" attitude, I got the same impression looking at several passages in his book...


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

"There's always a danger running in the enemy at close range" (Adm.W.F.Wake-Walker)

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Re: hits on PoW and Bismarck

Post by alecsandros » Tue Oct 09, 2018 7:42 am

Bill Jurens wrote:
Mon Oct 08, 2018 8:35 pm
except that if the hole in the shell were very large, as might have occurred if the projectile detonated inside the ship, it might have required Bismarck to reduce speed somewhat during the rest of the operation.
For the record, Bismarck did reduce speed during May 24th, at 22kts then at 16kts or lower, to conduct repairs.

Later, average speed based on coordinates existing at the time of the loss of contact (May 25th 03:00) and re-acquiring of contact (May 26th 10:20) was 21kts. Later it was increased to 25kts (average) , based on coordinates between re-acquiring of contact (10:20) and fatal attack (21:00).

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