KGV and PoW GAR during Op. Rheinubung

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Alberto Virtuani
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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Thu Oct 05, 2017 12:03 pm

Hi Duncan,
1) I'm not sure I understand your reasoning here, could you please elaborate ? I'm afraid I can follow you only by steps..... I see B2 gun fired in total 40 actual shells (not 40 ordered shots...), also, where is 9:44 coming from ?
What I'm saying in my point 1) is that gun n.4 in "Y" turret was able to fire 49 shells (actual) and was unable to bear or out of action for 28 minutes.
Even assuming a spectacular 95% (over 1 hour and half engagement....) output efficiency for this single gun, we have at least 80 (most likely 85) shots that could have been theoretically ordered for this gun. This gives a total of 800-850 shots potentially ordered, therefore around 700 shots actually ordered (850-112(Y turret wooded or out of action)-output loss(5 to 10%)).

2) The problem is not the traversing speed of the turret, but the time when the turrets were completely blinded due to the turns. Rodney had ALL her turrets wooded for 7 times during the battle. KGV only blinded Y turret twice and A+B turrets once (please see the map below)..... At 9:20 Rodney had just wooded once her turrets, so she could mantain still a good RoF, however when turning in front of Bismarck she surely couldn't.
Thus the total salvos ordered were surely many more for KGV than for Rodney.
KGV_May_27th_1941_track_01.jpg
KGV_May_27th_1941_track_01.jpg (86.09 KiB) Viewed 2376 times
I see your opinion, in my opinion your estimation of 550 shots ordered for KGV is absolutely unrealistic for both reasons above and a minimum of 700 should be assumed.

Again, our speculations cannot be proved in any way. :wink:


Bye, Alberto
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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Thu Oct 05, 2017 2:10 pm

I wrote: "therefore around 700 shots actually ordered (850-112(Y turret wooded or out of action)-output loss(5 to 10%))."
Hi Duncan,
I cannot edit anymore the above post and it's wrong. I see now I should have written: therefore around 700 shots actually ordered (850 or 800 - 112 (Y turret wooded or out of action) -18 (A+B turret wooded only once in the whole battle for 2 to 3 minutes).


Bye, Alberto
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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Thu Oct 05, 2017 10:22 pm

Alberto Virtuani wrote:Hi Duncan,
1) I'm not sure I understand your reasoning here, could you please elaborate ? I'm afraid I can follow you only by steps..... I see B2 gun fired in total 40 actual shells (not 40 ordered shots...), also, where is 9:44 coming from ?
What I'm saying in my point 1) is that gun n.4 in "Y" turret was able to fire 49 shells (actual) and was unable to bear or out of action for 28 minutes.
Even assuming a spectacular 95% (over 1 hour and half engagement....) output efficiency for this single gun, we have at least 80 (most likely 85) shots that could have been theoretically ordered for this gun. This gives a total of 800-850 shots potentially ordered, therefore around 700 shots actually ordered (850-112(Y turret wooded or out of action)-output loss(5 to 10%)).

2) The problem is not the traversing speed of the turret, but the time when the turrets were completely blinded due to the turns. Rodney had ALL her turrets wooded for 7 times during the battle. KGV only blinded Y turret twice and A+B turrets once (please see the map below)..... At 9:20 Rodney had just wooded once her turrets, so she could mantain still a good RoF, however when turning in front of Bismarck she surely couldn't.
Thus the total salvos ordered were surely many more for KGV than for Rodney.
KGV_May_27th_1941_track_01.jpg
I see your opinion, in my opinion your estimation of 550 shots ordered for KGV is absolutely unrealistic for both reasons above and a minimum of 700 should be assumed.

Again, our speculations cannot be proved in any way. :wink:


Bye, Alberto


Again, Rodney fired 375 rnds total with a 113 salvos with 77% output. Rodney fired for 87 minutes while KGV fired for 84 minutes. Rodney had the "weather gauge" and so had superior visibility during the action, and was on average, closer to Bismarck. When we take all these factors together we can see that the number of salvos fired would have been approximately the same for both ships.

1) A turret jammed at 0920 after firing an average of 23 rnds per gun. So at 0920 it is reasonable to suppose about 23 rnds/gun for B turret at 0920. B2 ceased fire after firing 40 rnds, so B2 must have ceased fire about 17 rnds or 34 salvos after A turret jammed and at 1.3 salvos/minute that means A2 jammed at 0920 + 26 mins + time spent turning = ~0949.

2) When Battleships turned their RoF will fall or cease completely. KGV turned ~90d or greater 4 times, while Rodney turned 90d or greater 7 times. OTOH, Rodney's greater speed of turret traverse equalized the loss of output so the variation in output that this caused was very minor. Rodney would only loose 45 to 60 secs per turn, or less, or none at all if the turn rate did not exceed the traverse rate.

more later.

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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Fri Oct 06, 2017 7:37 am

Hi Duncan,
thanks for your explanation.

I totally disagree with your assumption of the same number of salvos ordered for the two ships, it is unsupported by any evidence. Rodney was closer but she wooded her(all fore) turrets 7 times, while KGV just wooded the fore turrets once and "Y" turret twice. KGV course was much more stable than Rodeney's that continuously adjusted her course (see map above). Also you cannot dismiss the theoretical RoF (higher for KGV): at DS BS fired much slower than her theoretical RoF, at 1round/gun/minute, but PG (same visibility, sea state, etc....) fired proportionally much faster (2 rpgm), also below her theoretical RoF, but the proportion was indeed respected. Thus, to follow your reasoning, you have to multiply 550 per 1,333......


1) Other unsupported assumptions: A turret jammed after having firing 23 rounds/gun in average. In the whole action, A1 fired 22 shells, A3 fired 30. There is quite a big difference here... and you cannot say in any way that "around 23" shells are an exact number for all A guns. Assuming A3 ordered to fire 26 shells while A1 only 20 at 9:20 (as logical from above figure and no unrealistic 100% efficiency for any gun including A3 :negative: ), then the number of salvos must have been of 52 as minimum.
Also, you are mixing shots ordered and shells fired: B2 ceased fire after firing 40 rounds. This is all we know. We cannot know how many rounds were fired in the 52 semi-salvos until 9:20, possibly much less or much more than 23. Too many unsupported assumptions to get to your conclusion. :negative:

2) Why? At DS no ship ceased fire while turning (even while PoW turned 160° hard to port.... :wink:) and this is the reason why the turrets jammed. The turns that matters are ONLY the ones when turrets are blinded and Rodney had to cease fire 7 times, while KGV had to cease fire only once for fore turrets and twice for "Y" turret.


I repeat (it is an unsupported assumption as well, but at least a bit more realistic) that if Y4 was able to fire 49 shells (actual) and was out of action (or wooded) for 28 minutes (other 28, or even more, potential shells), with an outstanding efficiency of 90% or 95% , the total number of salvos that could have been potentially ordered was something between 80 and 85, thus 850 shots that could have been ordered. Even detracting the shots when Y was wooded or out of action and A+B were wooded, we still have something like 700 shots actually ordered for KGV vs.339 shells fired . :(


Bye, Alberto
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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Fri Oct 06, 2017 10:37 am

Alberto Virtuani wrote:Hi Duncan,
thanks for the explanation.

I totally disagree with your assumption of the same number of salvos ordered for the two ships, it is unsupported by any evidence. Rodney was closer but she wooded her(all fore) turrets 7 times, while KGV just wooded the fore turrets once and "Y" turret twice. KGV course was much more stable than Rodeney's that continuously adjusted her course (see map above). Also you cannot dismiss the theoretical RoF (higher for KGV): at DS BS fired much slower than her theoretical RoF, at 1round/gun/minute, but PG (same visibility, sea state, etc....) fired proportionally much faster (2 rpgm), also below her theoretical RoF, but the proportion was indeed respected. Thus, to follow your reasoning, you have to multiply 550 per 1,333......


1) Other unsupported assumptions: A turret jammed after having firing 23 rounds/gun in average. In the whole action, A1 fired 22 shells, A3 fired 30. There is a big difference here... and you cannot say in any way that "around 23" shells are an exact number for all A guns. Assuming A3 ordered to fire 26 shells while A1 only 20 at 9:20 (as logical from above figure and no unrealistic 100% efficiency for any gun including A3 :negative: ), then the number of salvos must have been of 52 as minimum.
Also, you are mixing shots ordered and shells fired: B2 ceased fire after firing 40 rounds. This is all we know. We cannot know how many rounds were fired in the 52 salvos until 9:20, possibly much less than 23. Too many unsupported assumptions to get to your conclusion :negative:

2) Why? At DS no ship ceased fire while turning (even while PoW turned 160° hard to port.... :wink:) and this is the reason why the turrets jammed. The turns that matters are ONLY the ones when turrets are blinded and Rodney had to cease fire 7 times, while KGV had to cease fire only once for fore turrets and twice for "Y" turret.


I repeat (it is an unsupported assumption as well, but at least a bit more realistic) that if Y4 was able to fire 49 shells (actual) and was out of action (or wooded) for 28 minutes (other 28 or even more potential shots) with an outstanding efficiency of 90% or 95% , the total number of salvos ordered could have been something between 80 and 85, thus 850 shots that could have been ordered. Even detracting the shots when Y was wooded or out of action and A+B were wooded, we still have something like 700 shots ordered for KGV.


Bye, Alberto
I have explained that the salvo rate was not set by the theoretical rate of fire, especially when two battleships were firing at the same target. Using your faulty logic one could argue that Rodney should have been able to fire 500 or more rnds instead of the 375 actually fired. Again, the salvo rate for Rodney and KGV was essentially identical.

I have patiently explained to you that Rodney's turrets could traverse at 4degs/sec. Another factor is that Rodney's track is only an approximation and Rodney's salvo chart shows good output at times when she is shown as wooding her turrets:
0916 - 0919 = 5 salvos

0938-0951 = 16 salvos (average for 0916-0919 and 0938-0951 = 21 salvos in 16 minutes or 1.3 salvos minute which matches her overall average)

0952-1014 = 20 salvos. (AFCT failure at ~0950 and some of these salvos were broadsides)

1)"... average of 23 rnds per gun..." at 0920 when A turret jammed is a direct quote from KGV's GAR. A1 fired 22 rnds up to the jam and then never fired after the jam because the 11A* loading tray interlock was too damaged for that tray to resume loading. After the turret was able to open fire at ~0950 only A2, A3 and A4 resumed firing, and they all eventually failed for other reasons.

2) Ships did cease fire when turning hard because fire wasn't accurate when under full helm. PoW only fired 2 ineffective salvos under director control when turning, and then never fired again even though A and B turrets were not wooded between ~0603:30 and ~0605:30. Bismarck's own output shows that she was not firing at anything close to her maximum RoF.


*11A interlock = interlock on 1A shell tray. I have used A1, A2 etc to designate guns by turret but the correct nomenclature was No.1 gun of A turret, etc.

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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Fri Oct 06, 2017 11:37 am

Hi Duncan,
I'm afraid that "I have patiently explained you" (your words) why your assumptions are unsupported and how you have made errors in your reconstruction....
you wrote: "Again, the salvo rate for Rodney and KGV was essentially identical. "
Where is this written ? This is your speculation only and just repeating it will not make it a fact.... :negative:
Why was the salvo rate different between BS and PG as they were firing at the Hood and at the PoW ? The salvo rate depends on the ship guns practical RoF, proportional to the theoretical and affected by visibility and sea state....
you wrote: "Rodney's track is only an approximation"
Please post a better track for both ships. The first data you post show 5 semi-salvos in 4 minutes that means fire was ceased for 2 minutes at least. All other data are average data and the fact that the average RoF was 1.3 is irrelevant: Rodney could NOT fire while her turrets (all fore by design) were wooded..... :negative:
you wrote: "A1 fired 22 rnds up to the jam "
Still we don't know how many rounds were fired by the other guns of A turret up to 9:20 AND we have no way to say that the salvos ordered were 46, 49, 55, or 60 because we don't know how many times A1 misfired or had other minor problems...... Your calculation is based on too many unproved hypothesis.
you wrote: "Ships did cease fire when turning hard"
Please, stay to facts. You have no proof of this at all and you are assuming unsupported facts..... PoW did fire at least 2 salvos while turning hard in central control (and just ceased fire because the director was wooded, else McMullen would have continued firing) and other 3 salvos in local control.... This is a fact.
Don't invent that on May 27 they did differently if you don't have any evidence in the GAR.



Please try to explain me how Y4 was able to fire 49 rounds, not firing for 28 minutes (wooded or jammed). :?:
The total number of shots ordered was most likely around 700 (for sure it cannot be 550 that would only be possible if Y4 fired for the whole time with an outstanding efficiency (90%) and no other gun fired during its "absence".....


In any case, I think we can easily agree that we both know too well that too few elements are available to get to any sound estimation. :wink:


Bye, Alberto
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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Fri Oct 06, 2017 8:11 pm

Alberto Virtuani wrote: Please try to explain me how Y4 was able to fire 49 rounds, not firing for 28 minutes (wooded or jammed). :?:
The total number of shots ordered was most likely around 700 (for sure it cannot be 550 that would only be possible if Y4 fired for the whole time with an outstanding efficiency (90%) and no other gun fired during its "absence".....
I roughly estimated the time that Y turret was wooded or turning to be 28 minutes, but a better estimate is 25 minutes; 12 minutes to 0900, 4 minutes from 0915, 7 minutes for the turret jam and ~2 minutes at ~1002.

Y4 fired 49 rnds which is equal to 98 salvos. 25 minutes @ 1.7 salvos/minute = 42 salvos while 25 minutes at 1.3 salvos/min = 32 salvos. So KGV's maximum number of salvos would have been 98 + 32 or 98 + 42 for 130 - 140 salvos. However during 18 minutes Y turret was wooded and this represents 18min x 1.7 salvos/min or 18min x 1.3 salvo/min or 31 - 23 salvos. Consequently the number of 5 gun salvos would be 109 if we use 1.7 salvos/min or 107 if we use 1.3 salvos/min. This means that maximum output would be 109 x 5 = 545 + 31 x 3 gun salvos for a total of 648 rnds or 107 x 5 = 535 + 23 x 3 gun salvos = 604 rnds.

The problem with the above is that KGV (like Rodney) used broadside firing during part of the latter half of the battle. Broadside firing temporarily raises the RoF of individual guns to above that which would be achieved in salvo firing, and this complicates using individual guns to estimate the total number of salvos fired.

We know that KGV fired 1.7 salvos/min from 0853 to 0913 when using type 284 ranging because this is stated in her GAR. IF KGV fired for 84 minutes at 1.7 salvos/minute this would = 143 salvos of which 112 would be 5 guns salvos and 31 would be 3 gun salvos. This gives a maximum possible output of 112 x 5 + 31 x 3 = 560 + 93 = 653 rnds. However KGV's salvo rate fell due to spotting and ranging difficulties before 0853 and after type 284 failed at 0913. KGV's average salvo rate from 0848 to 0920 was about 1.5 - 1.6 salvos per minute based upon the 23 rnd average for A turret at 0920 and about 50 salvos fired so therefore she fired about 16 salvos from 0848-0853 and 0913-0920 or ~16 salvos in 12 minutes or 1.33 salvos/minute which is very similar to Rodney under similar control conditions. Rodney's average salvo rate from 0847 to 0920 was 1.4 salvos/minute using purely optical ranging. Rodney's peak salvo rate, over 20 minutes, was from 0918 to 0938 when she fired 34 salvos in 20 minutes which was 1.7 salvos/min. If Rodney had been able to maintain that rate for the entire 87 minutes she would have fired 148 salvos but Rodney averaged 1.3 salvos/min over the entire action for 113 salvos.

We have peak salvo rates for both KGV and Rodney yet neither ship fired at it's peak salvo rate for the entire action.

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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Fri Oct 06, 2017 8:40 pm

Hi Duncan,
I see that finally, abandoning any unsupported assumptions, we are much more close in our estimate here and I will not even discuss the 25 or 28 minutes when Y4 was not firing: :clap:
you wrote: "This means that maximum output would be 109 x 5 = 545 + 31 x 3 gun salvos for a total of 648 rnds or 107 x 5 = 535 + 23 x 3 gun salvos = 604 rnds."
However, still you don't take into account the loss of output due to the unavoidable misfires and minor problems for Y4 gun (that was not the "miracle" gun). Assuming this gun was firing at an outstanding output efficiency of 90% (max 95%) during its engagement, we get a range for the ordered shots from a minimum of 635 (604 being the 95% of 635) to a maximum of 720 ordered shots (648 being the 90% of 720).


I agree about the difficulty to get to a final agreed figure, but I suspect 680 to 700 would be a realistic one. This gives an overall output efficiency for KGV slightly below 50%..... Luckily, HMS Rodney was there to do the job.


Bye, Alberto
Last edited by Alberto Virtuani on Fri Oct 06, 2017 8:54 pm, edited 1 time in total.
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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Fri Oct 06, 2017 8:47 pm

Alberto Virtuani wrote: Still we don't know how many rounds were fired by the other guns of A turret up to 9:20 AND we have no way to say that the salvos ordered were 46, 49, 55, or 60 because we don't know how many times A1 misfired or had other minor problems...... Your calculation is based on too many unproved hypothesis.
All the failures to fire for A1 and other guns are stated in the GAR. Because A1 stopped firing at 0920 we know how many rnds were requested from it.

22 rnds were fired by A1 before it stopped firing at 0920.
"...Slow loading...caused the turret to miss one salvo..." (this may or may not have effected A1 gun)
One or two salvos were missed owing to sticky interlocks: - N. 48 interlock at No.1 of "A" (from the GAR)
Therefore A1 gun was requested to fire 23 to 25 times from 0848-0920 and actually fired 22 times. The same number of rnds would have been requested from A2, A3, and A4 (and B1 and B2). This means that A2 turret jammed at salvo 46 to salvo 50 and therefore KGV fired 46 to 50 salvos prior to 0920.

We know that KGV fired 34 salvos from 0853-0913 and that means that a maximum of 16 salvos were fired outside of 0853-0913 up to 0920 or a maximum of 16 salvos in 12 minutes. As I showed in my last post this proves that KGV and Rodney's salvo rates were very similar when using similar control methods.

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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Fri Oct 06, 2017 8:59 pm

Hi Duncan,
I would basically agree with your explanation about A turret guns (assuming the GAR lists all the problems....). However, I'm sorry I don't understand your above conclusion.

Based on the "simple" analysis of Y4 gun, you suggested that the KGV ordered rounds were between 604 and 648. I have proposed a correction to keep into account the output efficiency of this specific gun (due to usual misfires and other minor problems) getting from 635 to 720 ordered shot and I have proposed a realistic range of 680 to 700 ordered shots and an overall output efficiency slightly below 50%.

This is a VERY different salvo rate than Rodney (based on which you were initially proposing 550 ordered shots), isn't it ?


Bye, Alberto
Last edited by Alberto Virtuani on Fri Oct 06, 2017 9:50 pm, edited 1 time in total.
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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Fri Oct 06, 2017 9:12 pm

Alberto Virtuani wrote:Hi Duncan,
I see that finally, abandoning any unsupported assumptions, we are much more close in our estimate here and I will not even discuss the 25 or 28 minutes when Y4 was not firing: :clap:
you wrote: "This means that maximum output would be 109 x 5 = 545 + 31 x 3 gun salvos for a total of 648 rnds or 107 x 5 = 535 + 23 x 3 gun salvos = 604 rnds."
However, still you don't take into account the loss of output due to the unavoidable misfires and minor problems for Y4 gun (that was not the "miracle" gun). Assuming this gun was firing at an outstanding output efficiency of 90% (max 95%) during its engagement, we get a range for the ordered shots from a minimum of 635 (604 being the 95% of 635) to a maximum of 720 ordered shots (648 being the 90% of 720).


I agree about the difficulty to get to a final agreed figure, but I suspect 680 to 700 would be a realistic one. This gives an overall output efficiency for KGV slightly below 50%..... Luckily, HMS Rodney was there to do the job.


Bye, Alberto
Y turret missed one or two salvos due to loading problems (GAR) - this is the only stated possible loss of output for Y4 and it may not have resulted in any lost output.
I agree about the difficulty to get to a final agreed figure, but I suspect 680 to 700 would be a realistic one. This gives an overall output efficiency for KGV slightly below 50%..... Luckily, HMS Rodney was there to do the job.
Alberto, after I spend countless hours carefully analysing KGV's and Rodney's output and presenting a carefully reasoned statement showing KGV's and Rodney's peak output and how that output fell during the entire action, you persist in trying to pretend that KGV could have maintained her peak output throughout the entire action.

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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Fri Oct 06, 2017 9:25 pm

Alberto Virtuani wrote:Hi Duncan,
I would basically agree with your explanation about A turret guns. However, I'm sorry I don't understand your above conclusion.

Based on the "simple" analysis of Y4 gun, you suggested that the KGV ordered rounds were between 604 and 648. I have proposed a correction to keep into account the output efficiency of this specific gun (due to usual misfires and other minor problems) getting from 635 to 720 ordered shot and I have proposed a realistic range of 680 to 700 ordered shots and an overall output efficiency slightly below 50%.

This is a VERY different salvo rate than Rodney (based on which you were initially proposing 550 ordered shots), isn't it ?


Bye, Alberto
Again, the only possible loss of output for Y4 was a loading problem that effected the whole of Y turret and caused it to miss 1 or 2 salvos, but this may not have caused any loss of output from Y4.

Alberto, I did not suggest that KGV's ordered rounds were 604 to 648! That would have been the number of requested rnds IF she maintained her maximum salvo rate for the entire action. I showed that KGV did not maintain her maximum salvo rate outside of 0853-0913 up to 0920 when I can analyse the salvo rate very accurately. The number of rnds fired by Y4 is complicated by the fact that KGV was using broadside firing during part of the latter half of the action and so Y4 was firing more often than every other salvo for part of the action.

Rodney requested 487 rnds and fired 375. Based upon that KGV probably requested 541 rnds while firing 339.

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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Fri Oct 06, 2017 9:31 pm

Hi Duncan,
I'm afraid that you missed too many things in your "carefully reasoned analysis"......I have spent too many hours already correcting your errors/speculations/erroneous inferences.....
you wrote: "the only possible loss of output for Y4 was a loading problem that effected the whole of Y turret and caused it to miss 1 or 2 salvos"
Not at all. Y turrets gun failures are NOT listed in detail in the GAR. Do you really believe that every single misfire is reported in the GAR ? :negative:

Y1 lost several salvos (22 vs 49 rounds) and this is (only partially) accounted for in the GAR.....
Y1 gun problem.jpg
Y1 gun problem.jpg (10.33 KiB) Viewed 2298 times
Y3 lost 12 shots compared to Y4 (37 vs 49) and NO reason is given for this.

Y2 fired very well (45 vs 49) but the GAR mention some problems for it.....
Y2 gun problem-1.jpg
Y2 gun problem-1.jpg (15.03 KiB) Viewed 2298 times
Y2 gun problem.jpg
Y2 gun problem.jpg (16.51 KiB) Viewed 2298 times
Where is the description of the severe problems occurred to Y3 gun ? (Y3 lost 25% of Y4 fired shots) :think:

In the same way there may be several lost shots for Y4 not described in the GAR because too trivial to be of any interest.



Your assumption that Rodney and KGV fired with the same salvo rate is TOTALLY UNSUPPORTED and it is the base for the your whole reasoning. :negative:

Please, READ what I post BEFORE posting (I beg your pardon if my English is not crystal clear). I accepted that KGV could not maintain her peak output, I accepted even your "discount" for the time Y turret was not in action, and thus I accepted YOUR proposed 604 to 648 ordered shots with 2 different RoF (1.3 and 1.7, not only the maximum one), I just proposed a correction to account for the unavoidable misfires and minor problems, NOT listed in the GAR.
you wrote: "Rodney requested 487 rnds and fired 375. Based upon that KGV probably requested 541 rnds while firing 339."
Duncan., you simply CANNOT make this assumption because it is totally unsupported. You are comparing apples with pears: different turret positions, different guns, different mountings, different shells, different battle geometry, different courses, mostly different reliability..... :negative:


Bye, Alberto
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Re: KGV and PoW GAR during Op. Rheinubung

Post by dunmunro » Fri Oct 06, 2017 10:22 pm

Alberto Virtuani wrote:Hi Duncan,
I'm afraid that you missed too many things in your "carefully reasoned analysis"......I have spent too many hours already correcting your errors/speculations.....
you wrote: "the only possible loss of output for Y4 was a loading problem that effected the whole of Y turret and caused it to miss 1 or 2 salvos"
Not at all. Y turrets gun failures are NOT listed in detail in the GAR. Do you really believe that every single misfire is reported in the GAR ? :negative:
Y1 lost several salvos (22 vs 49 rounds) and this is (only partially) accounted for. Y3 lost 12 shots compared to Y4 (37 vs 49) and NO reason is given for this. Y2 fired very well and the GAR mention some salvos lost for it.....
Where is the description of the severe problems occurred to Y3 gun ? :think:
In the same way there may be several lost shots for Y4 not described in the GAR because too trivial to be of any interest.

Your assumption that Rodney and KGV fired with the same salvo rate is TOTALLY UNSUPPORTED and it is the base for the your whole reasoning. :negative:

Please, READ what I post BEFORE posting. I accepted that KGV could not maintain her peak output, I accepted even your "discount" for the time Y turret was not in action, and thus I accepted YOUR proposed 604 to 648 ordered shots with 2 different RoF (1.3 and 1.7, not only the maximum), I just proposed a correction to account for the unavoidable misfires and minor problems, NOT listed in the GAR.
you wrote: "Rodney requested 487 rnds and fired 375. Based upon that KGV probably requested 541 rnds while firing 339."
Duncan., you simply CANNOT make this assumption because it is totally unsupported. You are comparing apples with pears: different turret positions, different guns, different mountings, different shells, different battle geometry, different courses, mostly different reliability..... :negative:


Bye, Alberto
Yes, every single gun failure is mentioned in the GAR. That's why GARs are written.

Y1 is fully accounted for: it lost several salvos prior to Y turret jamming and then failed to resume fire when Y turret resumed firing.
Y3 is fully account for; it missed one or two salvos due to the turret problem mentioned above and then suffered repeated loading failures due to the centre hoist shell retaining stop ( GAR p148, #10).
Your assumption that Rodney and KGV fired with the same salvo rate is TOTALLY UNSUPPORTED and it is the base for the your whole reasoning.
No. I proved that their salvo rates were very similar when using the same control methods and encountering similar visibility prior to 0920. Rodney's peak salvo rate occurred when she had excellent visibility and was closer to Bismarck than KGV.

Rodney's average salvo rate was 113/87 = 1.3 salvo/min. KGV fired for 84 minutes and at 1.3 salvos/min this equals 109 possible salvos. KGV could have fired 113 salvos in 84 minutes with 1.35 salvo/min, or slightly better than Rodney and still maintain proportional output.

I have proven that KGV fired from 46 to 50 salvos up to 0920 which included 20 minutes at her peak salvo rate due to type 284 radar ranging. Rodney fired 44 salvos up to 0920. Without type 284 KGV's salvo rate would have been nearly or completely identical to Rodney's.

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Alberto Virtuani
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Re: KGV and PoW GAR during Op. Rheinubung

Post by Alberto Virtuani » Fri Oct 06, 2017 10:36 pm

Hi Duncan,
thanks for showing Y3 failure in the GAR, I have missed it.

I see you still insist to compare apples with pears.
Rodney had to cease fire 7 times, KGV never wooded all her turrets together. Rodney course was much more complicated than KGV course (more stable), Rodney had (by design) a lower RoF, as logical mounting more heavy guns.
Also KGV was closing to Bismarck in the final stages of the battle, Rodney was closer but KGV should have augmented her salvo rate as well (I think Tovey himself asked to close, in order to put more shells on her) but you want to ignore this.

However I give up here, we can simply agree to disagree. My best estimate is 680 to 700 ordered shots for KGV, based on Y4 gun 49 fired shells, without firing for 25 (or 28) minutes out of 84, :shock: is yours still 550 now ?


Bye, Alberto
"It takes three years to build a ship; it takes three centuries to build a tradition" (Adm.A.B.Cunningham)

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