Bismarck analysis

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

Moderator: Bill Jurens

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Mon May 13, 2019 7:38 pm

alecsandros wrote:
Mon May 13, 2019 7:11 pm
dunmunro wrote:
Mon May 13, 2019 6:58 pm


Norfolk claimed that Rodney scored a hit or hits at ~0848 but if true, these hits could have only come from KGV since she had an accurate FC solution whilst Rodney was unable to obtain any optical ranges, early on, and did not claim any straddles until 0858 with salvo 18B.
Those times do not match German times, at all.
KGV did not have any "valid " FC solution, neither battleship had a "valid" FC solution for the first ~15minutes of firing (as atested by German survivor accounts). For some time, they didn't even knew which shell splashes they were watching.
This is from KGV's GAR while survivor accounts are necessarily made from memory only. There was initial confusion on KGV from about 0848-0852 until type 284 began to give continuous ranges from 21100 yds. By 0859 the range was down to ~16000 yds and by 0902 it would have been 15k yds and it is extremely unlikely, that Bismarck was not hit before then as both RN battleships had reported multiple straddles before then.

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Mon May 13, 2019 7:45 pm

alecsandros wrote:
Mon May 13, 2019 7:13 pm
paul.mercer wrote:
Mon May 13, 2019 8:49 am
Hi alecsandros,
Are you suggesting that there is now doubt whether it was a hit from Rodney or KGV that knocked out the forward turrets, I thought that it was generally accepted that it was a 16" hit that did the damage - or did one shell from each ship arrive around the same time and almost at the same place, which I presume is quite possible- and unfortunate from Bismarck's point of view?
It is unknown.
Most secondary sources mention HMS Rodney as scoring the "spectacular hit" against Bismarck at 9:02, but with the confusion reigning in the first ~ 15minutes from open fire , really anything was possible.

IMHO, a double hit from the same salvo (either from KGV or from Rodey) is possible, and a ricochet hit from a same shell (deflected from Anton into Bruno) is also possible, because of the existing battle geometry at the time (9:02 or so). If a double hit is considered, then I think Rodney is the more likely candidate for such a feat, as she was alternating fire of 4 and 5-gun salvoes, whereas KGV was alternating between 3 salvoes. Therefore the probability of a double hit is higher for Rodney. But all this is just an informed guess...
KGV and Rodney opened their A arcs at ~0900, prior to that both ships would have been firing 1/2 salvos of 3 guns each. After that, KGV would have fired 1/2 salvos of 5 guns each (until 0920), and Rodney alternating salvos of 4 and 5 guns.

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Mon May 13, 2019 7:50 pm

dunmunro wrote:
Mon May 13, 2019 7:38 pm
This is from KGV's GAR while survivor accounts are necessarily made from memory only. There was initial confusion on KGV from about 0848-0852 until type 284 began to give continuous ranges from 21100 yds. By 0859 the range was down to ~16000 yds and by 0902 it would have been 15k yds and it is extremely unlikely, that Bismarck was not hit before then as both RN battleships had reported multiple straddles before then.
Good shooting gives you straddles, but only God gives you hits.

KGV was behind Rodney, Rodney's smoke exhaust and smoke from gun barrels was obscuring KGV's spotting. For some time they did not know which salvo splashes belonged to which battleship.

Bismarck straddled Rodney at 3rd salvo, around 8:51, causing minor splinter damage, followed by an immediate course alteration performed by Rodney (slightly to the N-E), and by KGV (slightly to the S-E). Any information obtained by that point in terms of gunnery solution was useless, as the new courses required new calcuations and new trajectories of fire. In that time, Bismarck was moving erratically on a general Northernly course, in poor visibility and in the middle of a storm, that was causing 2-3 meter high waves and a considerable pitch to all involved ships. Therefore, first hits around 9:02 at 15000yards (if range is as you say) do not seem curious at all.

What is curious is why the crippled Bismarck straddled first.

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Mon May 13, 2019 7:52 pm

dunmunro wrote:
Mon May 13, 2019 7:45 pm

KGV and Rodney opened their A arcs at ~0900, prior to that both ships would have been firing 1/2 salvos of 3 guns each. After that, KGV would have fired 1/2 salvos of 5 guns each (until 0920), and Rodney alternating salvos of 4 and 5 guns.
Most maps put that wide-arc movement at 9:04 for KGV and 9:02 for Rodney.

Rodney had 9 guns available for firing between 8:47 and 9:02, and 9 guns available for firing form 9:02 onwards...
KGV had 6 guns available for firing in the initial phase , and 10 afterwards.

Even so, KGV expended about 10% less main battery shells then Rodney did, and 20% less main battery shells then Rodney did, when compensating for gun number (specifically KGV 339 shells with 10 guns, or 33,9shells/gun, and Rodney 375 shells with 9 guns, or 41,66 shells/gun).

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Mon May 13, 2019 7:58 pm

alecsandros wrote:
Mon May 13, 2019 7:52 pm
dunmunro wrote:
Mon May 13, 2019 7:45 pm

KGV and Rodney opened their A arcs at ~0900, prior to that both ships would have been firing 1/2 salvos of 3 guns each. After that, KGV would have fired 1/2 salvos of 5 guns each (until 0920), and Rodney alternating salvos of 4 and 5 guns.
Most maps put that wide-arc movement at 9:04 for KGV and 9:02 for Rodney.

Rodney had 9 guns available for firing between 8:47 and 9:02, and 9 guns available for firing form 9:02 onwards...
KGV had 6 guns available for firing in the initial phase , and 10 afterwards.

Even so, KGV expended about 10% less main battery shells then Rodney did, and 20% less main battery shells then Rodney did, when compensating for gun number (specifically KGV 339 shells with 10 guns, or 33,9shells/gun, and Rodney 375 shells with 9 guns, or 41,66 shells/gun).
Rodney's after turret cannot fire over B turret.

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Mon May 13, 2019 8:02 pm

dunmunro wrote:
Mon May 13, 2019 7:58 pm


Rodney's after turret cannot fire over B turret.
Not directly over it,
but Bismarck wasn't directly in front of Rodney. There was about 10-15deg offset between them in the beginning of the battle, and that was enough for all turrets to fire.
I seem to remember somebody quoted from Rodney's GAR, and it specifically mentioned salvo fire starting at 8:47, with alternations between 4-gun and 5-gun salvoes.

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Mon May 13, 2019 8:32 pm

alecsandros wrote:
Mon May 13, 2019 8:02 pm
dunmunro wrote:
Mon May 13, 2019 7:58 pm


Rodney's after turret cannot fire over B turret.
Not directly over it,
but Bismarck wasn't directly in front of Rodney. There was about 10-15deg offset between them in the beginning of the battle, and that was enough for all turrets to fire.
I seem to remember somebody quoted from Rodney's GAR, and it specifically mentioned salvo fire starting at 8:47, with alternations between 4-gun and 5-gun salvoes.
Rodney (From Robert's The Final Action) at ~0852 fired 2 salvos with A arcs open and 3 more from 0858 until opening them continuously from ~0904 and salvo 25. KGV's GAR states that she made an "emergency turn" at 0859 to open her A arcs and the tactical plot from the Battle Summary shows this as you can see here:

viewtopic.php?f=1&t=6834

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Tue May 14, 2019 5:50 am

dunmunro wrote:
Mon May 13, 2019 8:32 pm
Rodney (From Robert's The Final Action) at ~0852 fired 2 salvos with A arcs open and 3 more from 0858 until opening them continuously from ~0904 and salvo 25. KGV's GAR states that she made an "emergency turn" at 0859 to open her A arcs and the tactical plot from the Battle Summary shows this as you can see here:

viewtopic.php?f=1&t=6834
According to "HMS Rodney: The Famous Ships of the Royal Navy Series", by Iain Ballantine, the Rodney fired 104 salvos of alternating 4-gun or 5-gun, and 9 broadsides, during the entire engagement. It also notes turret X was the least active , as it could not fire directly ahead, and that numerous misfires occured.

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Tue May 14, 2019 6:35 am

alecsandros wrote:
Tue May 14, 2019 5:50 am
dunmunro wrote:
Mon May 13, 2019 8:32 pm
Rodney (From Robert's The Final Action) at ~0852 fired 2 salvos with A arcs open and 3 more from 0858 until opening them continuously from ~0904 and salvo 25. KGV's GAR states that she made an "emergency turn" at 0859 to open her A arcs and the tactical plot from the Battle Summary shows this as you can see here:

viewtopic.php?f=1&t=6834
According to "HMS Rodney: The Famous Ships of the Royal Navy Series", by Iain Ballantine, the Rodney fired 104 salvos of alternating 4-gun or 5-gun, and 9 broadsides, during the entire engagement. It also notes turret X was the least active , as it could not fire directly ahead, and that numerous misfires occured.
From:
http://www.kbismarck.com/rodney-gunnery-report.html
...In the action with the BISMARCK "X" turret could only bear on the target on 6 out of the first 25 salvoes. After the 25th salvo "X" could not bear on 9 occasions, making a total of 28 salvoes or broadside that "X" turret could not bear on the target...

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Tue May 14, 2019 7:56 am

Probably so.
That shows the Rodney had 3 more guns to bear then KGV did (9 guns versus 6), for 6 salvoes, in the initial phase.

KGV was also suffering from Rodney's smoke, and overall outputted less shells then Rodney did.

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Tue May 14, 2019 8:41 am

alecsandros wrote:
Tue May 14, 2019 7:56 am
Probably so.
That shows the Rodney had 3 more guns to bear then KGV did (9 guns versus 6), for 6 salvoes, in the initial phase.

KGV was also suffering from Rodney's smoke, and overall outputted less shells then Rodney did.
I am not sure why this matters but:

KGV opened her A arcs at salvo ~18.

So at salvo 25, KGV had fired 18 x 3 gun salvos and 7 x 5 gun salvos or 89 rnds.

At salvo 25 Rodney had fired 19 x 3 gun salvos and 3 x 5 gun salvo and 3 x 4 gun salvo, or 84 rnds. (assuming 100% output, but in fact KGV's output was probably a bit higher than Rodney's during this phase of the action. Rodney had 90% output up to ~0918, first 30min).

KGV maintained a higher salvo rate than Rodney from 0853 to 0913 (34 salvos vs 25) when her type 284 FC radar was working optimally and giving continuous ranges. After the type 284 failed at 0913 KGV relied more on optical ranging and then her poorer visibility became a factor. After 0920 KGV's output fell steeply. At 0913 kGV had achieved at least 14 straddles (GAR: 14 straddles from 0953 to 0913) to Rodney's 6 or 7 (according to her salvo chart).

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Tue May 14, 2019 8:55 am

Before you head to low down on the ridiculous path,
be advised that, according to "HMS Rodney: The Famous Ships of the Royal Navy Series", by Iain Ballantine, by salvo 4, Rodney had turret X and A with open arcs for fire.
At 9:02, Rodney observed an own salvo of 4-guns of which 2 gun splashes were seen - indicating either 2 misfires, 1 misfire and 1 hit, or 2 hits.

KGV's output per gun was 23% lower then Rodney's.

paul.mercer
Senior Member
Posts: 802
Joined: Fri Mar 26, 2010 10:25 pm

Re: Bismarck analysis

Post by paul.mercer » Tue May 14, 2019 9:32 am

alecsandros wrote:
Mon May 13, 2019 7:13 pm
paul.mercer wrote:
Mon May 13, 2019 8:49 am
Hi alecsandros,
Are you suggesting that there is now doubt whether it was a hit from Rodney or KGV that knocked out the forward turrets, I thought that it was generally accepted that it was a 16" hit that did the damage - or did one shell from each ship arrive around the same time and almost at the same place, which I presume is quite possible- and unfortunate from Bismarck's point of view?
It is unknown.
Most secondary sources mention HMS Rodney as scoring the "spectacular hit" against Bismarck at 9:02, but with the confusion reigning in the first ~ 15minutes from open fire , really anything was possible.

IMHO, a double hit from the same salvo (either from KGV or from Rodey) is possible, and a ricochet hit from a same shell (deflected from Anton into Bruno) is also possible, because of the existing battle geometry at the time (9:02 or so). If a double hit is considered, then I think Rodney is the more likely candidate for such a feat, as she was alternating fire of 4 and 5-gun salvoes, whereas KGV was alternating between 3 salvoes. Therefore the probability of a double hit is higher for Rodney. But all this is just an informed guess...
Hi alecsandros,
Thanks for the info, whoever fired the shots it had a detrimental effect on Bismarck's potential firepower.

alecsandros
Senior Member
Posts: 4344
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Bismarck analysis

Post by alecsandros » Tue May 14, 2019 10:01 am

paul.mercer wrote:
Tue May 14, 2019 9:32 am

Hi alecsandros,
Thanks for the info, whoever fired the shots it had a detrimental effect on Bismarck's potential firepower.
Certainly so.
One of the turrets remained silent , and the other one only managed to fire one shot at around 9:30 or so.

The knocking out of the forward batteries was a result of Adm. Tovey's decision to attack from the front, in order to use a massive superiority of firepower against the enemy (15 main guns versus 4 main guns)

dunmunro
Senior Member
Posts: 3887
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: Bismarck analysis

Post by dunmunro » Tue May 14, 2019 10:01 am

alecsandros wrote:
Tue May 14, 2019 8:55 am
Before you head to low down on the ridiculous path,
be advised that, according to "HMS Rodney: The Famous Ships of the Royal Navy Series", by Iain Ballantine, by salvo 4, Rodney had turret X and A with open arcs for fire.
At 9:02, Rodney observed an own salvo of 4-guns of which 2 gun splashes were seen - indicating either 2 misfires, 1 misfire and 1 hit, or 2 hits.

KGV's output per gun was 23% lower then Rodney's.
I gave you direct quotes from Rodney's GAR
From:
http://www.kbismarck.com/rodney-gunnery-report.html
...In the action with the BISMARCK "X" turret could only bear on the target on 6 out of the first 25 salvoes. After the 25th salvo "X" could not bear on 9 occasions, making a total of 28 salvoes or broadside that "X" turret could not bear on the target...
Is there something in the above that you don't understand?

Post Reply