Bismarck and her contemporaries

Discussions about the history of the ship, technical details, etc.

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alecsandros
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Re: Bismarck and her contemporaries

Post by alecsandros »

sineatimorar wrote: Hence inclusion of PG into the mission ( as a result of the river plate battle maybe?).
... I don't know.
From what I've read, the Prinz was the only large ship available at the time, as the pocket battleships were to slow, and Schar+Gneis+Hipper were in repairs/refits...
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Shell hole in Bismarck's Bow

Post by Bill Jurens »

As a co-author of the paper cited in a recently posted memo, I would like to assure readers that the allocation of specific holes to specific projectile hits in the bow area remains, at best, highly speculative. The paper makes it sound as though the identification of the holes was definitive, but it really is not, i.e. there was no firm concensus amongst the authors that could clearly associate any specific pair (or group) of holes to the bow damage suffered on 24 May. I was unable to definitively identify any specific pair of holes, port and starboard, that could be unequivocally be associated with the projectile hit whilst simultaneously remaining in accordance with other physical evidence, ballistic analysis, and the observations of eye-witnesses, etc. I tried, very hard, examining the detailed videotape obtained on one expedition and my own personal 'eyeballs on' examinations conducted on another expedition to try to clearly identify specific entrance and exit holes. I could not find any pair or set of holes that were fully in accordance with descriptions provided by the German eye-witnesses whilst still being ballistically plausible, especially when it cannot even be determined whether or not the projectile actually exploded before or after exit. The condition of the wreck indicates that a neatly welded patch would extremely difficult to detect at all, meaning that one or more of the holes in the shell plating may be there but hidden.

In summary, although there is an understandable temptation to wish to identify "THE" holes definitively, but I don't think the evidence available really enables us to do that yet. Further examination is required. In that regard, I think it historically counter productive at this stage to claim that the association of any set of specific holes (and, by implication, the description of these holes) with the damage caused by the British projectile hit on 24 May has been in any way definitively established.

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Re: Bismarck and her contemporaries

Post by sineatimorar »

Thanks Bill for the clarification. I do not know why it seems to be important to people if this hole was patched or not, as from what I understood the reserves supply was for the PG? The hit to the side on the torpedo bulkhead seems to be the more likely hit that caused the mission to be aborted would you not agree? Some other areas of that report in conclusions seems to be a little speculative in nature as well. Interesting info on the refueling at Norway been cut short by a hose beakage was it? One point Iam a bit fuzzy on is the final position of the remaining rudder. Was it pushed back to it current position when the stern section fell off, or when it pushed thru the impact crater wall when it hit bottom? I realize at the time of the report there had been no survey of the crater.
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Re: Bismarck and her contemporaries

Post by tommy303 »

Interesting info on the refueling at Norway been cut short by a hose beakage was it?
If I recall correctly, the hose breakage incident, which cut short fueling for Bismarck, occurred not in Norway, but at Gotenhafen before the start of the sortie. On arrival at Bergen, Norway, Prinz Eugen refueled from a tanker, but the stay was cut short by the need to keep up with the weather system developing in the Arctic in order to reach the Denmark Straits before it had a chance to begin clearing. Consequently there was insufficient time to move the tanker to Bismarck and refuel her as well. Thus, Prinz Eugen left Norway with full bunkers, but Bismarck did not and sailed with just the remaining fuel of that taken on in Poland.

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Re: Bismarck and her contemporaries

Post by Bill Jurens »

Sineatimorar wrote:

"The hit to the side on the torpedo bulkhead seems to be the more likely hit that caused the mission to be aborted would you not agree?"

I don't consider myself a tactical expert, but my guess is that the real problem was that regardless of damage suffered once Bismarck had been located, and experience showed that she could be successfully tracked, that the Germans saw little point in continuing the operaton. She would have little chance of intercepting weaker forces or convoys, etc. by accident, and the Royal Navy would have simply tracked her down relentlessly. Under those circumstances, and especially with damage already suffered, rather than conduct what would amount to a suicide mission, the best approach might well have been to head for port and perhaps try again later.

"Iam a bit fuzzy on is the final position of the remaining rudder. Was it pushed back to it current position when the stern section fell off, or when it pushed thru the impact crater wall when it hit bottom?"

This is probably somewhat like the question "Did the British sink the Bismarck or did the Germans scuttle her", to which the best answer is probably "yes". It appears that the rudder was pushed (albeit perhaps briefly) far enough forward by the torpedo blast to damage a propeller, and that and probably moved some distance aft afterwards due to hydrodynamic forces. It is unclear how much the position of the rudder might have been affected by the slide down the bottom, but my intiution suggests that it was not a great deal. The important fact is that the damage to the rudder -- however it looked -- was, right from the initial explosion time unfixable outside of a drydock.

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Re: Bismarck and her contemporaries

Post by sineatimorar »

Thanks again Bill for your the further clarification. It a pity that the port rudder has disappeared as we will never really know its final position. I wonder how much hydrodynamic effect the starboard rudder would have had in it, lets us say initial, damaged position, considering how hard it was to maintain heading in trials with rudders in a locked position? It seems even if both rudder had detached after the hit the ship in all probability would have been just as uncontrollable, considering wind and sea conditions.

I find some similarities between the damage state just post the rudder hit and the situation faced by the Pod W's final battle with shaft tunnels been flooded etc. Once the crews damage control abilities were eroded to the point of scuttling his fate was sealed. The debate over was it the torpedos, gunfire, or scuttling charges relatively immaterial as the BS's fate would not have changed either way once the steering was blown away.

regards Jason.
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Re: Bismarck and her contemporaries

Post by tommy303 »

Hi Jason,

You might find a great deal of similarity here as well:

http://www.researcheratlarge.com/Ships/ ... ering.html

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Re: Bismarck and her contemporaries

Post by sineatimorar »

Hey thanks tommy, just shows up how difficult it is when you do get lucky. Any damage to the propellers/ shafts and it would have been a different story.
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Re: Bismarck and her contemporaries

Post by tommy303 »

The report also hints at the difficulties the Bismarck may have had if it had been possible to successfully detach the rudders with explosives as was suggested on board after attempts at steer on props failed. Bismarck's rudders were skeg-less and her hull was quite clean to reduce drag, and without even the jammed rudders, she might have been virtually impossible to control.

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Re: Bismarck and her contemporaries

Post by sineatimorar »

Maybe that is why they did not do it, unlike the intrepid, the Bismarck's designer was on board for this voyage; He would have been perfectly aware of this would you not think?
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Re: Bismarck and her contemporaries

Post by tommy303 »

Possibly, but I think there was also a fear that unless you were very precise in the amount of explosive to use, one might do more damage than good, particularly to the nearby props. In any event, the high seas made it almost a certainty that an attempt to plant explosives at the right spot would likely fail. For all intents and purposes, I think that the situation was pretty hopeless given the circumstances in play at that time.

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Re: Bismarck and her contemporaries

Post by sineatimorar »

No arguments here. The last point of interest on the report I read is on the the fact that the main AAA mounts were unable to depress their barrels low enough to engage the swordfish. The impression I got was it was been suggested this was a design fault in the AAA system maybe? With a max depression angle of either -8° to -10°, I think the only 'design' fault would have been the placement on the deck of theses mounts. Attacks head on or from directly astern were out of the arcs of fire of most mounts. Interesting question on what steering practices were utilized in defense against the air attack, I.E. Something like Japanese practices of rapid individual manoeuvres or manoeuvres that were in response to avoid the attacks? I forgotten how much the BS held over with max rudder applied, I read that he could lose as much as 16 to19 knots, which means his forward speed at the time of the fateful hit may have been as low as 7 to 10 knts!
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Re: Bismarck and her contemporaries

Post by tommy303 »

I am not sure if the heavy Flak was unable to depress enough to engage--I don't think that was really a major problem with at least some of the mountings. Bismarck was fitted with the older Dop. L C/31 mountings in the four forward and the newer Dop. L. C/33 mountings in the four aft. The C/31 had the -8 to + 80 degree depression/elevation limits, while the newer C/33 had -10 degree depression. The two mountings had differing elevation and traverse rates as well. The older C/31 mountings were not fully integrated into the heavy Flak fire control system which was designed around the C/33. Both Bismarck and Tirpitz entered service with their Flak battery split between the older and newer mountings, and was probably due to the haste in which the ships were completed and put into service. It was intended, I believe to replace the C/31 mountings with the C/33 as they became available. Bismarck was sunk before this could be done, but Tirpitz received hers in the fall of 41. An additional problem in Bismarck was her being sent to sea on her first mission before the two aft spherical triaxle heavy Flak directors were ready (the two aft ones for Bismarck and the two forward ones for Prinz Eugen had been sold to the USSR in fulfillment of treaty obligations and the replacement ones were not completed in time for Rheinuebung). Instead, a simple twin axis range finder was fitted in each of the two aft positions. This, her lack of intensive Flak practice, and the mixed mountings probably accounted for her lack of success in engaging the swordfish as they came in to drop their ordnance. Tirpitz did rather better a year later when put to the test.

I most certainly agree that the fields of fire of the heavy and medium Flak was entirely inadequate leaving uncovered gaps in the fore and aft sectors. The AVKS report is rather critical of this if I recall.

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And saved the sum of things for pay.
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Re: Bismarck and her contemporaries

Post by Francis Marliere »

Gentlemen,

as far as I remember, there were others factors explaining the failure of Bismarck flak against Swordfishes.

First, Bismarck flak was not outstanding. Heavy flak was never very succesfull against low flying planes, and the 'failure' of 10.5 cm guns was not surprising. The German 3.7 cm gun was semi-automatic and its slow rate of fire made it almost useless. Hence the Bismarck relied on 12 2 cm C30 guns which were only marginaly better (according to http://www.navweaps.com/Weapons/WNGER_20mm-65_c30.htm "The C/30 model was prone to jamming and used a small magazine (20 rounds) which meant frequent pauses for reloading").

Second, the guns had little firing time since the planes emerged from the clouds at short range. In the opposite, Tirpitz shot down several Albacore when engaged in 1942, because she could fire for a long time : the planes where detected far away and slowly catched the ship due to their slow speed and strong headwind.

Third, the conditions were difficult. The ship was rolling and pitching, and visibility was very bad. Planes were difficult to see and gunners were blinded by the flash of their guns.

Best,

Francis Marliere
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Re: Bismarck and her contemporaries

Post by alecsandros »

... And the crew was quite tired, after being under constant stress for allmost 3 days.
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