Page 1 of 2

Bismarck and Tirpitz a myth?

Posted: Sun Sep 16, 2018 5:18 pm
by paul.mercer
Gentlemen,
I’m going to put my hand in the fire here (actually both hands!) and ask a question which may outrage some of you, but here goes!
Do you think that ever since the Denmark Strait battle a myth about the power and almost invincibility of both Bismarck and Tirpitz has grown up around these two ships? Very powerful, well-armed and well armoured and probably the best available in any fleet at the time almost certainly, but anyone without much knowledge of naval history who was looking back through some of the threads and debates of the past in this forum would gather that these ships were so good that practically nothing short of an Iowa or Yamoto would be capable of taking then on one to one and that their armour was so strong that it was almost immune to 14/15/16” shell fire. We have had many debates on either of these two versus almost every other battleship in the world and the general opinion seems to favour them over everything except the latest and largest US and Japanese ships.
Certainly it appears that after Hood was sunk and PoW battered the RN almost had a panic attack about Bismarck or Tirpitz getting out, with Churchill apparently ordering that two KGV class plus the USS Washington be available to guard against it, but there even has been doubts cast on the ability of Washingon (Tirpitz v Washington thread) being able to take care of Tirpitz on her own and serious doubts as to whether a single KGV would survive against her.
Obviously we know the ultimate end of both ships, one to a very fortunate torpedo hit and the other to several 6 ton bombs which no ship could survive, but despite the general opinion of the KGV’s, I wonder if a fully worked up KGV with decent radar (Duke of York?) and all guns working as they should might not have been a match for Tirpitz? After all, although she may not be capable of sinking Tirpitz (and we generally agree it was very difficult to sink a modern battleship by gunfire) the combined firepower of 10x14” would have been enough to damage Tirpitz so badly that any accompanying RN cruisers or destroyers would have a chance to torpedo her, or Tirpitz being a bit faster might have disengaged and headed back to Norway?
In other words gentlemen, were they really as good as history seems to make them?

Re: Bismarck and Tirpitz a myth?

Posted: Sun Sep 16, 2018 6:44 pm
by alecsandros
I tried to do some hypotheticals some time ago (I think 2 years) here on the forum,
with various battleship classes being used as a swap to Bismarck during op. Rheinubung. Most fared much worse then Bismarck did.

In my opinion, in May 1941, Bismarck was more powerfull then tipically thought of. She was handicapped by the mission chosen and by a green crew with an incomplete and not fully operational equipment on board.

As she was, with a fully integrated radar-fire-control, automatic solutions for turret train and elevation (executed automatically by use of gyros and servos controlled by the main fire control computers) , very fast rate of fire (for a battleship), high speed and long range, the Bismarck was the terror of the seas at her time. British analysis post-1945 revealed her multiple armor-array as making the ship practically unsinkable by gunfire (allthough she could be reduced to a floating mass of twisted steel with no military value whatsoever).

===

In her 6 days mission (May 22nd - May 27th), she fired against HMS Norfolk, Suffolk, Sheffield (all straddled and all damaged or with splinters and casualties on board); HMS Hood, HMS Prince of Wales, HMS Rodney, HMS KGV (all straddled; Hood sunk, PoW damaged, Rodney damaged by splinters, KGV straddled); HMS Piorun, Maori, Cossackh, Sikh, Zulu (all 5 straddled; 4 of them damaged by splinters and with casualties on board). She also fired against 26 aircraft (1 Short Sunderland, 1 PBY Catalina, 24 Swordfish. No planes were shot down, but 8 Swordfish were damaged so badly as they couldn't fly the next day)

Re: Bismarck and Tirpitz a myth?

Posted: Sun Sep 16, 2018 7:10 pm
by dunmunro
alecsandros wrote:
Sun Sep 16, 2018 6:44 pm
...very fast rate of fire (for a battleship)...
Yet A/A tell us that their RoF was glacially slow and only capable of 93 rounds over 14 minutes, even when all 8 x 38cm guns can bear on the target.

Re: Bismarck and Tirpitz a myth?

Posted: Sun Sep 16, 2018 7:43 pm
by Paul L
dunmunro wrote:
Sun Sep 16, 2018 7:10 pm
alecsandros wrote:
Sun Sep 16, 2018 6:44 pm
...very fast rate of fire (for a battleship)...
Yet A/A tell us that their RoF was glacially slow and only capable of 93 rounds over 14 minutes, even when all 8 x 38cm guns can bear on the target.
Such is the nature of target acquisitionS.

Re: Bismarck and Tirpitz a myth?

Posted: Mon Sep 17, 2018 9:35 am
by alecsandros
dunmunro wrote:
Sun Sep 16, 2018 7:10 pm
Yet A/A tell us that their RoF was glacially slow and only capable of 93 rounds over 14 minutes, even when all 8 x 38cm guns can bear on the target.
AVKS of March 1941 gives 23 to 25 rpm for all 8 guns.

Re: Bismarck and Tirpitz a myth?

Posted: Mon Sep 17, 2018 9:15 pm
by wadinga
Hello Alecsandros,

Long time no see, welcome back.
AVKS of March 1941 gives 23 to 25 rpm for all 8 guns.
I presume this means reload time in seconds for each gun being c.20 seconds? So nearly 3 rounds per gun per minute. How often was this achieved?

All the best

wadinga

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 7:10 am
by alecsandros
wadinga wrote:
Mon Sep 17, 2018 9:15 pm
I presume this means reload time in seconds for each gun being c.20 seconds? So nearly 3 rounds per gun per minute. How often was this achieved?
All the best

wadinga
Hello,
the numbers come from AVKS700, or intensive gunnery exercises performed in March 1941 (some days of tests between 15 to 28th of March)*.
I consider this to be the upper limit of the gunnery system in terms of rate of fire. Other parts of AVKS hint towards elevation angles of corresponding to 5000 to 25000m firings. A supposition can be made that the 23 to 25 rpm corresponds to different ranges, thus different elevations of guns, and thus different times required for elevating/depressing the guns. But it's only a supposition.

*There were also intensive gunnery trials in April 1941, but I have not seen any records about it.
Of note is also that the battleship was modified in April and May, and some of those modifications may have affected the firing methodology and thus rate of fire (ex instalment of transmission cables between main radar set and fire control computers , by Siemens engineers, to improve gunnery accuracy)

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 7:32 am
by Herr Nilsson
The results 23 rpm and 25 rpm in the AVKS does not apply for the reload time, but the main hoists! The minimum reload time is 26 seconds according the time table for ammunition supply and loading operation. The minimum cycle of the shell hoist cage is 26 seconds (2.3 rpm) and in regard of the cartridge hoist cage is 24 seconds (2.5 rpm). IMHO it's a typo and they simply forgot a decimal dot (comma in German).

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 8:29 am
by alecsandros
I know.
Bear in mind though that the "minimums" are usualy average minimums, and not technological minimums.
For instance, US 16"/L50 mounted in the triple turrets of USS Washington had a "minimum" reload cycle of 32 seconds, but 25seconds were obtained during gunnery exercises at low elevation of the gun (2.45 shots per minute per gun , average for all 9 guns).

Alas, this complete reload cycle (from extracting the shell from the magazine to it's firing off the gun barell) is more of a myth, as most WW2 battleships had several shells stored inside, or near, the main turrets, therefore being much more easily loaded and fired. Most battles were very short , and featured starkly different firing times for early , mid and late phase of the battle - accounting for both the use of turret-stored ammo as well as crew fatigue and mechanical troubles developing over time.

Therefore, the problem of rate of fire , IMHO , is more of a problem of obtaining and KEEPING a correct fire control solution, against which the main turrets can fire multiple times at maximum rate of fire.

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 8:55 am
by Herr Nilsson
What about cartridges?

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 9:19 am
by alecsandros
the powder cartridges or the ejected cartridges ?

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 11:40 am
by Herr Nilsson
Powder. I was referring to this sentence:
alecsandros wrote:
Tue Sep 18, 2018 8:29 am
Alas, this complete reload cycle (from extracting the shell from the magazine to it's firing off the gun barell) is more of a myth, as most WW2 battleships had several shells stored inside, or near, the main turrets, therefore being much more easily loaded and fired.
A shell without a cartridge is rather useless.

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 11:51 am
by alecsandros
Don't know for sure, but I suppose they kept a few shots worth of powder inside the turret, or immediately below it.

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 12:52 pm
by Herr Nilsson
Ok, I understand. No, there were only shells and no powder in case of Bismarck. I think the ready use shells were mainly used when the main hoists were out of order, because the auxiliary hoists could only transport either shells or cartridges in one cycle.

Re: Bismarck and Tirpitz a myth?

Posted: Tue Sep 18, 2018 1:12 pm
by alecsandros
How fast where the auxiliary hoists ? Could they deliver the powder fast enough to keep up with firing of ready use ammo ?