Message Traffic heard by RODNEY 24 May 1941

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

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Tue May 21, 2019 5:19 am

Bill Jurens wrote:
Mon May 20, 2019 8:20 pm
FWIW, I have records, from USN target practices, of quite a few first salvo straddles on targets at ranges well over 20,000 yards, even before WWII. So such an occurrence, while unusual, was by no means unknown, especially if the first salvo pattern was fairly large.

Bill Jurens
I don't discount the possibility in general,
but the actual occurrence on that day and place.

Straddling an obscured target at 20km, in a gale storm, with own ship pitching heavily on heavy seas, against an erratically moving enemy, is a complicated thing to do. Further - obtaining hits - is exceptionally unlikely. HMS Duke of York consumed over 300 shells in the pursuit (not including initial short range fire and final barrage fire) of the Scharnhorst, ranges 15 to 20km, and obtained no more then 3-4 hits in 1 hour, while using a far more advanced radar system (which was capable of producing visuals of own shells in flight as well as shell splashes around the enemy).

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Tue May 21, 2019 5:24 am

northcape wrote:
Tue May 21, 2019 12:13 am
If everybody would follow this example it would solve the problem quickly. I can only encourage everybody to do the same in order to restore rationality, purpose, and common sense in the forum. There is nothing to be gained in providing a stage and audience for this kind of behavior and endless repetition of opinions.
Why doesn't that surprise me ?

So far I see only attempts at not accepting the body of evidence presented. This is everybody's choice, but putting it high in the air and making a case out of not accepting the best reconstruction of facts available so far, is arrogant and childish.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by northcape » Tue May 21, 2019 6:22 am

alecsandros wrote:
Tue May 21, 2019 5:24 am
northcape wrote:
Tue May 21, 2019 12:13 am
If everybody would follow this example it would solve the problem quickly. I can only encourage everybody to do the same in order to restore rationality, purpose, and common sense in the forum. There is nothing to be gained in providing a stage and audience for this kind of behavior and endless repetition of opinions.
Why doesn't that surprise me ?

So far I see only attempts at not accepting the body of evidence presented. This is everybody's choice, but putting it high in the air and making a case out of not accepting the best reconstruction of facts available so far, is arrogant and childish.
Please be more accurate/less manipulative.

There is a clear difference between (a) "accepting a reconstruction as an opinion/possibility" and (b) "accepting that an opinion (this specific reconstruction) is wrongly represented as the "truth" (or "the best reconstruction")". I have no issues with (a), but as many others here I'm very tired of (b). In particular since the approach for this reconstruction violates standard scientific practices (neglecting/over-estimating accuracies of input data, using results of the reconstruction to prove itself (circuar logic), using "soft data" such as propagands paintings as input/factual information, using only selected evidence such as isolated eye-witness reports).

And what do you actually mean by "best" reconstruction? How do you measure this? It is just like in cooking - if you take many ingredients of diverse origins, and simply mix and boil them in a single pot without any preparation you will most likely not get a tasty dish.

An objective relative measurement of the "goodness" of a specific reconstruction would be a robust estimate of the associated errors of the reconstructed positions, but this of course is not provided (it also would be quite a stretch given the sparseness of the input data). Otherwise there is no possibility to validate any reconstruction as you don't have any ground truth to check your reconstruction.

I"m not using the words "arrogant and childish", but I can think of other adjectives to describe the lack of understanding of simple scientific principles, such as that a theory is not proven by the absence of alternative theories. And talking of "acceptance", I think it is also high time for some forum members to accept that a majority of other members are of the opinion that the sparseness of the input data does not allow a reconstruction to that level of detail as postulated by Mr. B. (and having that opinion, they simply see no point in attempting an alternative or any reconstruction).

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Tue May 21, 2019 6:51 am

History is not mathematics.
This reconstruction is the "best" only until a better one comes along.

So far you and other members have been repeatedly asked to provide a better alternative , which you failed to do.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by northcape » Tue May 21, 2019 7:07 am

alecsandros wrote:
Tue May 21, 2019 6:51 am
History is not mathematics.
This reconstruction is the "best" only until a better one comes along.

So far you and other members have been repeatedly asked to provide a better alternative , which you failed to do.
History is not Mathematics, but both need to operate under scientific principles if they intend to have any purpose.

For the rest of your statements, I invite you to read (and try to understand) my posting again, in particular the last paragraph.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Tue May 21, 2019 7:20 am

northcape wrote:
Tue May 21, 2019 7:07 am
History is not Mathematics, but both need to operate under scientific principles if they intend to have any purpose.

For the rest of your statements, I invite you to read (and try to understand) my posting again, in particular the last paragraph.
Squirming around the arguments won't help you escape from the responsibility of not providing meaningfull results.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by northcape » Tue May 21, 2019 7:28 am

alecsandros wrote:
Tue May 21, 2019 7:20 am
northcape wrote:
Tue May 21, 2019 7:07 am
History is not Mathematics, but both need to operate under scientific principles if they intend to have any purpose.

For the rest of your statements, I invite you to read (and try to understand) my posting again, in particular the last paragraph.
Squirming around the arguments won't help you escape from the responsibility of not providing meaningfull results.
I invite you to think and try to understand my posting again, in particular the last paragraph.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by Alberto Virtuani » Tue May 21, 2019 7:30 am

Hello everybody,
"If everybody would follow this example it would solve the problem quickly"
...and I can only repeat that the absence of answer from such forum members is more than welcome by me !

I always answer to points raised in a fair way but I see that when without arguments (see examples: viewtopic.php?f=1&t=8552&start=75#p83563, viewtopic.php?f=1&t=8552&start=75#p83565, viewtopic.php?f=1&t=8552&start=105#p83598, viewtopic.php?f=1&t=8552&start=135#p83637, viewtopic.php?f=1&t=8552&start=150#p83658, just in this last thread...), people (even the most "authoritative"...) are running away and changing topic, protected by the "moderator" redactions.
This is not a productive way to discuss and will led to nowhere, thus the "retreat" of these poeple has to be considered a very good step ahead.


Of course, Alec is right in pointing out the total absence of any alternative recontruction/explanation in view of the available evidences (except using risible arguments like, "indeterminateness", "fog of war", "lack of GPS", "typos", "elderly memories", etc. etc.). The fact that nobody has been able to reconstruct the battle better than Antonio did, shows by itself that his one is still the best possible historical reconstruction up to now, inconvenient and annoying as it can be for a certain side...


Bye, Alberto
Last edited by Alberto Virtuani on Tue May 21, 2019 8:04 am, edited 1 time in total.
"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: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Tue May 21, 2019 7:34 am

northcape wrote:
Tue May 21, 2019 7:28 am

I invite you to think and try to understand my posting again, in particular the last paragraph.
I invite you to reconsider your attitude , as you are not in a position to criticise people who produced substantial research on their free time and consuming their energy.

Your irrelevant replies and meaningless circular logic won't help you here.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by Byron Angel » Tue May 21, 2019 12:44 pm

alecsandros wrote:
Tue May 21, 2019 7:20 am
northcape wrote:
Tue May 21, 2019 7:07 am
History is not Mathematics, but both need to operate under scientific principles if they intend to have any purpose.

For the rest of your statements, I invite you to read (and try to understand) my posting again, in particular the last paragraph.
Squirming around the arguments won't help you escape from the responsibility of not providing meaningfull results.

Do we REALLY need more acrimony here, Alecs? I think not. Please.

B

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by Byron Angel » Tue May 21, 2019 1:15 pm

alecsandros wrote:
Tue May 21, 2019 5:19 am
Bill Jurens wrote:
Mon May 20, 2019 8:20 pm
FWIW, I have records, from USN target practices, of quite a few first salvo straddles on targets at ranges well over 20,000 yards, even before WWII. So such an occurrence, while unusual, was by no means unknown, especially if the first salvo pattern was fairly large.

Bill Jurens
I don't discount the possibility in general,
but the actual occurrence on that day and place.

Straddling an obscured target at 20km, in a gale storm, with own ship pitching heavily on heavy seas, against an erratically moving enemy, is a complicated thing to do. Further - obtaining hits - is exceptionally unlikely. HMS Duke of York consumed over 300 shells in the pursuit (not including initial short range fire and final barrage fire) of the Scharnhorst, ranges 15 to 20km, and obtained no more then 3-4 hits in 1 hour, while using a far more advanced radar system (which was capable of producing visuals of own shells in flight as well as shell splashes around the enemy).

Big difference between these engagements in my opinion. North Cape was fought at night in Force 5 weather conditions and certainly worse visibility conditions. Much of Duke of York's shooting was conducted as radar-controlled "blind fire". Her Type 284 was of an improved model, but was still not truly blind fire capable due to insufficient bearing resolution. True blind fire capability did not appear until fairly late in the war (Mk 13 FC radar in the USN, for example).

Excerpted from Appendix III - Gunnery Summary – Duke of York
[ 1 ] The action was fought in “complete darkness” with “a high wind and a medium sea”.
[ 2 ] “A large number of straddles for range were observed by radar during the blind firing phase of the action but in the conditions prevailing it is unlikely that many of these were in line. “



FWIW.

B

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by Dave Saxton » Tue May 21, 2019 2:07 pm

Byron Angel wrote:
Tue May 21, 2019 1:15 pm
alecsandros wrote:
Tue May 21, 2019 5:19 am
Bill Jurens wrote:
Mon May 20, 2019 8:20 pm
FWIW, I have records, from USN target practices, of quite a few first salvo straddles on targets at ranges well over 20,000 yards, even before WWII. So such an occurrence, while unusual, was by no means unknown, especially if the first salvo pattern was fairly large.

Bill Jurens
I don't discount the possibility in general,
but the actual occurrence on that day and place.

Straddling an obscured target at 20km, in a gale storm, with own ship pitching heavily on heavy seas, against an erratically moving enemy, is a complicated thing to do. Further - obtaining hits - is exceptionally unlikely. HMS Duke of York consumed over 300 shells in the pursuit (not including initial short range fire and final barrage fire) of the Scharnhorst, ranges 15 to 20km, and obtained no more then 3-4 hits in 1 hour, while using a far more advanced radar system (which was capable of producing visuals of own shells in flight as well as shell splashes around the enemy).

Big difference between these engagements in my opinion. North Cape was fought at night in (IIRC) worse weather conditions and certainly worse visibility conditions. Much of Duke of York's shooting was conducted as radar-controlled "blind fire". Her Type 284 was of an improved model, but was still not truly blind fire capable due to insufficient bearing resolution. True blind fire capability did not appear until fairly late in the war (Mk 13 FC radar in the USN, for example).

Excerpted from Appendix III - Gunnery Summary – Duke of York
[ 1 ] The action was fought in “complete darkness” with “a high wind and a medium sea”.
[ 2 ] “A large number of straddles for range were observed by radar during the blind firing phase of the action but in the conditions prevailing it is unlikely that many of these were in line. “



FWIW.

B
The bearing resolution of Type 284 was quite good. From British engineer Bryan Callick, who was involved in the design and development of British radar during the war:
Type 284 the first naval fire control system, operated at 600 mhz, and used transmitting and receiving arrays having 24 dipoles in horizontal cylindrical mirrors to obtain a 3 degree beam in the horizontal plane
Mk8 was 2 degrees and Type 281 was 10 degrees for some perspective. The 1/2 power horizontal beam width is the bearing resolution. Callick's data was for the early Type 284 because it is for separate transmitting and receiving arrays. It would be for max signal.

Lobe switching or beam switching of the transmitted beam resulted in wider beams or a degrading of bearing resolution, however. For example, employing beam switching on MK3 effectively doubled the bearing resolution from ~ 7 degrees to ~15 degrees. Lobe switching typically improved the accuracy of bearing determination using max signal from 3/4 degree to 1 degree to within 1/10 degree, but degraded bearing resolution.

Later marks of the 284 employed beam switching, but they also combined both the receiving and transmitting arrays, so they could be used at the same time, effectively doubling the effective size of the antenna. This increases the antenna gain exponentially and decreases the beam width.

The film posted by Duncan shows how 284 was used:

viewtopic.php?f=13&t=8475
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Tue May 21, 2019 3:01 pm

Byron Angel wrote:


Do we REALLY need more acrimony here, Alecs? I think not. Please.

B
you're right, my bad.
I'll be happy to reply to any rational argument brought forward.

Best,

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by alecsandros » Wed May 22, 2019 9:44 am

Byron Angel wrote:
Tue May 21, 2019 1:15 pm
Big difference between these engagements in my opinion. North Cape was fought at night in Force 5 weather conditions and certainly worse visibility conditions. Much of Duke of York's shooting was conducted as radar-controlled "blind fire". Her Type 284 was of an improved model, but was still not truly blind fire capable due to insufficient bearing resolution. True blind fire capability did not appear until fairly late in the war (Mk 13 FC radar in the USN, for example).

Excerpted from Appendix III - Gunnery Summary – Duke of York
[ 1 ] The action was fought in “complete darkness” with “a high wind and a medium sea”.
[ 2 ] “A large number of straddles for range were observed by radar during the blind firing phase of the action but in the conditions prevailing it is unlikely that many of these were in line. “



FWIW.

B
The final battle of Bismarck was also fought in appalling weather:

extract from Adm Tovey's dispatch - sinking of Battleship Bismarck:

'Weather:
Wind - North-west, force 8.
Weather - Overcast; rain squalls.
Visibility - 12 - 13 miles.
Sea and swell - 45.'

[...]

'Choice of Tactics
79. It was clear from the reports of the ships which had come under her fire that, in spite of the damage she had already received from guns and torpedoes, the gun armament and control of the Bismarck were not seriously affected. Everything suggested, however, that her rudders had been so seriously damaged that she could not steer; in the strong wind prevailing, she could, by working her engines, haul off the wind only for short periods. So it was possible for me to select the direction and time of my approach and close to whatever range I chose. The experience of the Fourth Destroyer Flotilla made it clear that the Bismarck had R. D/F which ranged accurately up to 8,000 yards; by day, she could range very accurately up to about 24,000 yards, either by means of the excellent stereoscopic rangefinders the Germans have always had or possibly by R. D/F.

80. I decided to approach with the advantages of wind, sea and light as nearly end-on as possible, so as to provide a difficult target and to close quickly to a range at which rapid hitting could be ensured. I hoped that the sight of two battleships steering straight for them would shake the nerves of the rangetakers and control officers, who had already had four anxious days and nights.

The Approach

81. Between 0600 and 0700, D/F bearings of a series of reports by the Maori enabled the relative position of the enemy to be deduced with reasonable accuracy. The Bismarck had settled down to a course of about 330°, at 10 knots. The horizon to the north-eastward was clear and the light good, but south of east were rain squalls and a poor background. The strong wind and heavy sea made it most undesirable to fight to windward. I decided to approach on a bearing of west-north-west and, if the enemy held his course, to deploy to the southward, engaging him on an opposite course at a range of about 15,000 yards and subsequently as events might dictate. At 0737, when the enemy bore 120°, 21 miles, course was altered to 080° to close; Rodney was stationed on a bearing of 010° and instructed not to close within six cables of me and to adjust her own bearing. The Norfolk was shadowing from the north-westward, ready to carry out flank marking for the battleships; and at 0820 she came insight and provided me with a visual link. It had been necessary to alter course on the way in to avoid rain squalls and to allow for the reported alterations of course of the Bismarck, but at 0843 she came in sight, bearing 188° , 25,000 yards, steering directly towards us, our course at this time being 110°.
'

http://www.hmshood.org.uk/reference/off ... 9tovey.htm

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Re: Message Traffic heard by RODNEY 24 May 1941

Post by paul.mercer » Thu May 23, 2019 9:06 am

Byron Angel wrote:
Tue May 21, 2019 3:53 am
northcape wrote:
Tue May 21, 2019 12:13 am
dunmunro wrote:
Mon May 20, 2019 6:30 pm
Therefore while I will continue to contribute to the forum I will no longer respond to any of his posts.
If everybody would follow this example it would solve the problem quickly. I can only encourage everybody to do the same in order to restore rationality, purpose, and common sense in the forum. There is nothing to be gained in providing a stage and audience for this kind of behavior and endless repetition of opinions.

Hi northcape,
A dramatic step by any measure. But, given the current situation and the stakes involved (i.e., the long term heath and viability of this forum), it is worthy of serious consideration. I too am quite frustrated with the current situation.

B
Gentlemen,
Agreed!

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