How close was the final battle?

[marcelo_malara]

The hipper would not using the penetration tables, but I don't understand why it's penetration was so low. It's about 1/4 the penetration of the bismarck with 1/2 the sectional density.

May because her guns were "just" 8"...?

[Mustang]

The hipper would not using the penetration tables, but I don't understand why it's penetration was so low. It's about 1/4 the penetration of the bismarck with 1/2 the sectional density.

May because her guns were "just" 8"...?

I'll accept your argument, I suppose the thread is over.

[Bill Jurens]

@ Mustang:

If my records are correct, it appears that you have entered this forum very recently and have, during your period here, presented some observations and conclusions that others are finding, let us say, 'somewhat controversial'. As you are no doubt aware, some have expressed concerns that at least some of your comments may not be intended sincerely. I do not have enough information to even begin to coherently comment on that, but my experience has been that in many cases it only leads to a series of 'flame wars' which end up requiring moderator intervention.

This sort of situation can easily arise if a member posts only under a pseudonym, e.g. in your case 'Mustang'. In such cases, it is extremely difficult for others to determine who you really are and your likely knowledge-base, i.e. to assess the probable validity of your observations. You could be a senior naval architect with thirty years of experience (in which case they might listen more closely), or you could be a teenager living in your mother's basement, who really is deliberately 'trolling' the group (in which case they can safely ignore you completely.) But as it is, nobody knows...

In that regard, I wonder if you might want send me, and perhaps other members, some more information about your background in naval history and/or naval technology, so that it might be easier to establish your credibility as a commentator. If, for whatever reasons, you wish to remain fully anonymous, that remains your right, but if you choose to take that course, you are likely to be -- fairly or unfairly -- judged on that. One convenient alternative would be to send me a private message and reveal some details about your background there. I could then take that message and pass some details on an open post membership, so that your credentials, in effect, are more fully qualified, but your actual identity remains, for whatever reasons, obscure.

I think at this stage, some additional information that might fully clarify your background in these areas might be helpful. Would you be willing to participate in introducing yourself a little more fully?

Bill Jurens
(as moderator)

[Mustang]

@ Mustang:

If my records are correct, it appears that you have entered this forum very recently and have, during your period here, presented some observations and conclusions that others are finding, let us say, 'somewhat controversial'. As you are no doubt aware, some have expressed concerns that at least some of your comments may not be intended sincerely. I do not have enough information to even begin to coherently comment on that, but my experience has been that in many cases it only leads to a series of 'flame wars' which end up requiring moderator intervention.

This sort of situation can easily arise if a member posts only under a pseudonym, e.g. in your case 'Mustang'. In such cases, it is extremely difficult for others to determine who you really are and your likely knowledge-base, i.e. to assess the probable validity of your observations. You could be a senior naval architect with thirty years of experience (in which case they might listen more closely), or you could be a teenager living in your mother's basement, who really is deliberately 'trolling' the group (in which case they can safely ignore you completely.) But as it is, nobody knows...

In that regard, I wonder if you might want send me, and perhaps other members, some more information about your background in naval history and/or naval technology, so that it might be easier to establish your credibility as a commentator. If, for whatever reasons, you wish to remain fully anonymous, that remains your right, but if you choose to take that course, you are likely to be -- fairly or unfairly -- judged on that. One convenient alternative would be to send me a private message and reveal some details about your background there. I could then take that message and pass some details on an open post membership, so that your credentials, in effect, are more fully qualified, but your actual identity remains, for whatever reasons, obscure.

I think at this stage, some additional information that might fully clarify your background in these areas might be helpful. Would you be willing to participate in introducing yourself a little more fully?

Bill Jurens
(as moderator)

I am not hiding my identity at all, and I don't care if I'm banned, I think this thread has reached its conclusion.

I don't have any naval experience myself but my dad was in the navy on a carrier as an electrician. My mom is also an engineer working on nuclear weapons related issues. I'm 31.

I understand if not being a naval engineer is a reason to ban, but I actually have a degree in a related field and have some engineering knowledge.

My Linkedin.

[Bill Jurens]

@ Mustang:

Thank you very much for your linkdin. That's very cooperative, and I'm sure other members will find the content very useful. As did I.

Don't worry about banning. We're all very patient here, and -- now that we know a little more about you -- can more easily assess -- and coherently respond to -- your comments.

Again, thanks for the quick and informative reply...

Bill Jurens

[RF]

In Denmark Strait, with a perfectly controllable ship, she hit Hood with one out of 24 shells fired (?, 6 salvos of 4 guns?), what gives a standard 5% hit rate.

Regards

There were three hits that we know about - one on the third salvo starting/adding to the fire on the midships section immediately after the first hit by Prinz Eugen, one hit on the fourth salvo which took away the Hood's foretop gunnery control and then the fatal hit on the fifth salvo. That gives 15% with the possibility that there was more than one hit with the fifth salvo.

[fsimon]

My two cents on how close the last battle was:
Not close at all!
Two versus one is a clear thing on my mind:
Lets say, Bismarck's shots get too close to Rodney's liking. Rodney starts to chase salvos, i.e. maneuvers defensively. This denies Bismarck to get hits on Rodney, while Rodney also has trouble to hit Bismarck, but not quite as musch since Bismarck herself can not maneuver much and is also very slow. At the same time King George V has no need to maneuver at first, since he is not targeted, and at the same time has the relatively easy task of targeting the almost non maneuvering Bismarck. As soon as Bismarck might realize that KGV is now the more dangerous threat and targets him (Sorry, I have troubles calling a George a "her".), now KGV could start maneuvering while the now untargeted Rodney is free to stabilice and zero in on Bismarck.
Does this make any sense?
Best regards
Frank

[Steve Crandell]

My two cents on how close the last battle was:
Not close at all!
Two versus one is a clear thing on my mind:
Lets say, Bismarck's shots get too close to Rodney's liking. Rodney starts to chase salvos, i.e. maneuvers defensively. This denies Bismarck to get hits on Rodney, while Rodney also has trouble to hit Bismarck, but not quite as musch since Bismarck herself can not maneuver much and is also very slow. At the same time King George V has no need to maneuver at first, since he is not targeted, and at the same time has the relatively easy task of targeting the almost non maneuvering Bismarck. As soon as Bismarck might realize that KGV is now the more dangerous threat and targets him (Sorry, I have troubles calling a George a "her".), now KGV could start maneuvering while the now untargeted Rodney is free to stabilice and zero in on Bismarck.
Does this make any sense?
Best regards
Frank

It makes sense in a war game. I don't think in real life Rodney would have been able to shoot at all under those circumstances.

[fsimon]

Hallo Steve,
I don't think this is only valid for war gaming, but also for the real battle on May 27th.
In fact Rodney did start to chase salvos after Bismarck stradled her with her second salco and splinters caused damage on Rodney. And I also think that the first hits on Bismarck were achieved by KGV while not beeing targeted himself. Bismarck shot very good initially, only spoiled by Rodneys maneuvering, then by getting a hit from untargeted Norfolk on the primary director, that also killed the 1st artillery officer Schneider.
KGV also maneuvered in zig zag to spoil Bismarck's shooting as soon as she was under fire.
So actually it was a 3 versus 1, with one or two ships always beeing untargeted or only targeted by Bismarck's secondary artillery.
Best regards
Frank

[paul.mercer]

Hi Mustang,
I don’t think that anyone would want to ban you from the Forum, most Forums have some ‘controversial’ subjects which are often quite useful in awakening interest, particularly when it has occasionally been a bit ‘dormant’ for a while, (one went to 151 posts on this Forum a while ago).
I hasten to add that I am not an ‘expert’ on Naval (or any other) subjects, my main interest is WWI & WW 2 naval warfare, and although I have read many of the available books on Bismarck, the Denmark Strait battle and its aftermath, most of the knowledge I have gained is by reading (and learning) from the posts from the people whom I consider as experts in this Forum - Bill Jurens being one of the foremost. If you look back on all the subjects listed, you will find that you can ask almost anything on a considerable variety of subjects on warfare and there will be somebody who will be able to give you advice.
This of course does not stop you from voicing your own opinion on any topic that you wish to bring up, but it is always worth having a look back at past topics to see if a particular point that you are interested in has been answered before, particularly the Demark Strait and the final battle which has been discussed in its various forms a number of times.
In the end you may not agree with them, but because of the vast amount of knowledge available from contributors in this Forum, it’s always worth reading and learning from what they have to say.

[dunmunro]

My two cents on how close the last battle was:
Not close at all!
Two versus one is a clear thing on my mind:
Lets say, Bismarck's shots get too close to Rodney's liking. Rodney starts to chase salvos, i.e. maneuvers defensively. This denies Bismarck to get hits on Rodney, while Rodney also has trouble to hit Bismarck, but not quite as musch since Bismarck herself can not maneuver much and is also very slow. At the same time King George V has no need to maneuver at first, since he is not targeted, and at the same time has the relatively easy task of targeting the almost non maneuvering Bismarck. As soon as Bismarck might realize that KGV is now the more dangerous threat and targets him (Sorry, I have troubles calling a George a "her".), now KGV could start maneuvering while the now untargeted Rodney is free to stabilice and zero in on Bismarck.
Does this make any sense?
Best regards
Frank

KGV and Rodney (to a lesser extent) could shoot accurately whilst maneuvering to chase salvos since the AFCT would compensate for own ship movement. OTOH, Bismarck's erratic motion did give both KGV and Rodney problems since their AFCT predicted on the basis of straitline target motion (as did all WW2 FC systems).

[fsimon]

Hallo Dummunro,
I doubt that Rodney and KGV would shoot very accurately while maneuvering. Did the AFCT get continuous inputs and thus provided continuous firing solution (like on the German C38 or the US Mark 37 FCS), or had it to be fed with data for every new calculation, i.e. were results generated at intervals? Rodney and KGV used "follow the pointer" weapon aiming and thus had another delay in using the calculated firing solution. This would make firing while maneuvering inaccurate. I would think, that they would make their maneuver, recalculate thereafter and then shoot with the new inputs.
Best regards
Frank

[marcelo_malara]

Hallo Dummunro,
I doubt that Rodney and KGV would shoot very accurately while maneuvering. Did the AFCT get continuous inputs and thus provided continuous firing solution (like on the German C38 or the US Mark 37 FCS), or had it to be fed with data for every new calculation, i.e. were results generated at intervals? Rodney and KGV used "follow the pointer" weapon aiming and thus had another delay in using the calculated firing solution. This would make firing while maneuvering inaccurate. I would think, that they would make their maneuver, recalculate thereafter and then shoot with the new inputs.
Best regards
Frank

I think so, Since the Dumaresq Mk V (Electric Dumaresq) own ship course is automatically fed into it, and so done it is then automatically fed into the Dreyer table. Anyway, I am quiet convinced that no mechanical firing computer do an exact calculation.

[dunmunro]

Hallo Dummunro,
I doubt that Rodney and KGV would shoot very accurately while maneuvering. Did the AFCT get continuous inputs and thus provided continuous firing solution (like on the German C38 or the US Mark 37 FCS), or had it to be fed with data for every new calculation, i.e. were results generated at intervals? Rodney and KGV used "follow the pointer" weapon aiming and thus had another delay in using the calculated firing solution. This would make firing while maneuvering inaccurate. I would think, that they would make their maneuver, recalculate thereafter and then shoot with the new inputs.
Best regards
Frank

Yes, the AFCT did get contiguous inputs:
Gyro compass
Gyro director gunsight - continuous bearing and level inputs
range (radar and optical, where available, which was used to set the range rate which the AFCT continuously generated)
cross level

and it generated continuous outputs:
range
bearing

The TIC gear (Time Interval Compensation) was used to compensate for any delays in the firing circuit. Since there was only one salvo/30sec there was lots of time for the turret layer and trainer to match pointers, and pointer matching (FTP) is theoretically more accurate than remote power control because of the lower inertia of the follow the pointer method. Remote power control systems suffered from servo lag, which forced a reduction in accuracy to prevent 'servo hunting' and oscillation in the gun laying and training. The USN used FTP for battleship main armament throughout 1942, including 2nd Guadalcanal and Casablanca.

This from Renown's report of the action against S&G:

The HIPPER meanwhile had been firing rapidly at RENOWN but without obtaining any hits. She had been engaged by the starboard 4.5 inch battery at a range of 18, 000 to 20,000 yards. At this range the fall of shot of these small 4.5 inch shell were only seen intermittently and the control officer adopted the tactics of firing blind ladders across the best obtainable rangefinder range.

During this and subsequent periods I took advantage of the agility of the modern fire control now fitted in RENOWN to alter course within small limits as necessary to prevent the enemy establishing hitting.

As soon as the SCHARNHORST broke off the action and turned away, HIPPER started to draw across making smoke to try and screen her. The fire of the main armament was then shifted to HIPPER, who, after the first salvo, also turned abruptly and joined her consort in flight. She, however, swung occasionally to bring her “A” arcs to bear and fire a broadside. This finished the main part of the action, which lasted twenty minutes.

[Byron Angel]

Hallo Dummunro,
I doubt that Rodney and KGV would shoot very accurately while maneuvering. Did the AFCT get continuous inputs and thus provided continuous firing solution (like on the German C38 or the US Mark 37 FCS), or had it to be fed with data for every new calculation, i.e. were results generated at intervals? Rodney and KGV used "follow the pointer" weapon aiming and thus had another delay in using the calculated firing solution. This would make firing while maneuvering inaccurate. I would think, that they would make their maneuver, recalculate thereafter and then shoot with the new inputs.
Best regards
Frank

Hi fsimon,
I won't speak to the shooting of KGV on 27 May, but the Dalrymple-Hamilton Action Report regarding RODNEY is pretty explicit about her poor gunnery on that day. First of all, RODNEY had not yet been fitted with any radar. As a consequence, all range and bearing inputs relied upon optical instruments The ship's Inclinometers were singled out as a comprehensive failure in terms of measuring target ship relative bearing and range-finding results were considered poor as well. RODNEY's AFCT Table broke down during the action as well.

RODNEY still employed WW1-era manual "Follow-the-Pointer" control of gun elevation and train for her main battery guns. Full RPC (remote power control) by automatic servo-mechanisms were already in use in the USN for both train and elevation and for elevation in the KM.

In addition, RODNEY relied upon manual cross-levelling to establish a stable vertical reference point; this involved two observation telescopes aimed 90deg apart - one aimed upon the horizon ahead, the other aimed upon the horizon abeam - both manually operated by gunnery ratings responsible for continuously maintaining the crosshairs of their respective telescopes upon the horizon as the ship rolled and pitched in order to track ship's attitude and motion in relation to true vertical. The basic concept was theoretically sound, but the efficacy of manual operations diminished rapidly as sea state worsened.

One of my pet peeves about the great fire control debate is that it seems to always focus upon the elegant theory underlying design of the gunnery control computing computing devices and largely ignores the quality of the target data inputs - we are essentially talking about today's "GIGO" effect here - "Garbage in; Garbage out".

Devils and details.

B