PoW's gunnery VS BSM's gunnery

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Re: PoW's gunnery VS BSM's gunnery

Post by Herr Nilsson » Fri Apr 05, 2019 11:14 am

Alberto Virtuani wrote:
Fri Apr 05, 2019 7:46 am

In the absence of any further (reasoned and supported) denial / (credible) alternative, can we consider that the points 1), 2) 3) and 4) are by now fully accepted as average figures for PoW and BS Rate of Fire ?


Also can we agree that the PG film battle sequence starts at around 06:04, for the reasons explained here (viewtopic.php?f=1&t=8491&start=435#p82759) ?
No.

No.
Regards

Marc

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Re: PoW's gunnery VS BSM's gunnery

Post by Alberto Virtuani » Fri Apr 05, 2019 11:22 am

Q.E.D.

....(supported/reasoned) denials, (credible) alternatives... A two letters word is not enough to prove anything.


Bye, Alberto
Last edited by Alberto Virtuani on Fri Apr 05, 2019 11:39 am, edited 3 times in total.
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Re: PoW's gunnery VS BSM's gunnery

Post by HMSVF » Fri Apr 05, 2019 11:23 am

Alberto Virtuani wrote:
Wed Apr 03, 2019 8:24 am
Hello everybody,
northcape wrote: "It is an arithmetic mean, but the arithmetic mean is just a number which in this case does not tell anything about the effectiveness of fire"
Correct. Means values are what we are trying to calculate (despite a huge resistance). All the other parameters (including effectiveness of fire, etc), are listed here (viewtopic.php?f=1&t=8491&start=315#p82614) and can be discuss each of them one by one, if needed, but only once we get consensus at least about the average RoF values...


Wadinga wrote: "the account does not actually say which salvoes were missed... a gun that has not been fired cannot be described as being "in action"...the Captain would surely notice how, of the six guns in front of him, one was completely dead, and two others were missing several sequential salvoes"
The available posted parts of Barben report + McMullen GAR give all relevant information to evaluate with a good degree of probability (I would not say 100% reliability) when B turret failed to fire, quite before salvo 16, as suggested to Mr.Cag after his description of the main shell ring. We can re-open this discussion once agreed on means values, however.

Of course, a gun loaded and ready to fire has to be considered in action at the end of the engagement, but this is probably not the case of B turret.

As the compass platform hit happened at around 06:00:50, the order to the helmsman given at 06:01:01-06:01:10 and the actual PoW turn actually stared at 06:01:30 (please, present any alternative timing matching what we see in PoW charts), we know that the "shaken" Leach could not see ANY salvo after salvo 15 (or at least he could not have based a rational decision based on what was happening outside the Bridge).
Salvo 16 happened very few seconds after the compass platform hit (see images from the film, sorry for my limited editing skill, as the last image has not the same contrast/definition of the previous ones, anybody can check at minute 6:46-6:50 of the PG film https://www.youtube.com/watch?v=pPmkOtSveXY):


PoW_compass_hit_salvo 16.jpg



Dunmunro wrote: "GO McMullen did not have access to Bismarck's GAR and so couldn't compile comparable data for Bismarck...and unfortunately neither can we."
...but very "fortunately" we have the precise number of shells fired, thus we can simulate any number of ordered shots / semi-salvo and get to the same identical conclusions: PoW RoF was in any case comparable to Bismarck's (viewtopic.php?f=1&t=8491&start=315#p82614). Sorry for that.


Bye, Alberto

Morning all.


A quick question. If Hood was sunk at 06:00 hrs and the compass hit was at 06:00 and 50 seconds that means that Schneider was able to switch targets, fire and hit within a matter of seconds?

Are the shell splashes short or long? If they are short doesn't that mean that the shell which went through the compass platform had a completely different angle of fall than the rest of the salvo, I mean the compass platform was way up high in the bridge structure, I'd imagine it didn't come down at an angle of 45 degrees, presumably it would fall at I dunno, 10 to 20 ?Ditto if the salvo was long presumably that one shell would have had an angle of fall different to the others? How far long or short would they have had to be? A question Mr Jurens would be able to help me out with!



So sharp shooting Schneider was able to switch targets and hit a matter of seconds and would have been bang on the money for following salvos? No wonder Leach turned away. He would have suffered a right kicking.




Best wishes!

HMSVF



Sorry, additional!


The shell that struck the compass platform didn't explode as far as I'm aware ? So there must have been an entry and exit hole? Unless the shell tumbled/ricocheted it would have gone straight through, so there would have been an angle of decent? Wouldn't the rest of the shells (if high landed a fair distance behind POW?

Always willing to learn !


Best wishes HMSVF

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Re: PoW's gunnery VS BSM's gunnery

Post by Alberto Virtuani » Fri Apr 05, 2019 11:38 am

Hello everybody,
HMSVF wrote: "that means that Schneider was able to switch targets, fire and hit within a matter of seconds?
Apparently he was: Hood exploded at 6:00, PoW turned away at 6:01:30 reacting to her rudder (all her maps) , therefore the order was given to the helmsman at 6:01 or max 6:01:10.
The hit happened before the order to turn away (Leach himself tells that in his official narrative), therefore 6:00:50 seems reasonable and perfectly matching the film showing the BS salvo landing and immediately after the PoW salvo 16 fired (at 6:00:50) download/file.php?id=3456.
Range was the same and everybody (including the Baron) agree that Schneider had no problem (and no delay) changing target. Therefore, as flight time of the 15" shell was around 23 secs at that distance, Schneider had almost 30 seconds to 1) realize Hood had exploded and 2) order the change of target: a remarkable switch fire, but nothing impossible.
Note in the PG film that PoW has not yet reached the Hood's remains (also accounting for a non-immediate stop of Hood after explosion) at 6:00:50 (at 29 knots PoW advances by 900 meters per minute), therefore the timing is IMO precise enough.

HMSVF wrote "Are the shell splashes short or long?"
I see them both as slightly more "centered" toward the bows of PoW (there was possibly no accuracy in changing the bearing so quickly), one short and one long, but it's a matter of opinions I guess (download/file.php?id=3456).

HMSVF wrote: "The shell that struck the compass platform didn't explode as far as I'm aware ? "
Correct.
Here the link to the thread where this hit has been discussed at length (the link points to the photo of the final exit hole viewtopic.php?f=1&t=6276&start=90#p59705 but the whole thread should be read).
All photos (with entry and exit holes from the CP are available here http://www.hmshood.com/history/denmarks ... amage1.htm)


Bye, Alberto
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Re: PoW's gunnery VS BSM's gunnery

Post by Bill Jurens » Fri Apr 05, 2019 4:15 pm

HMSVF wrote:

"Are the shell splashes short or long? If they are short doesn't that mean that the shell which went through the compass platform had a completely different angle of fall than the rest of the salvo, I mean the compass platform was way up high in the bridge structure, I'd imagine it didn't come down at an angle of 45 degrees, presumably it would fall at I dunno, 10 to 20 ?Ditto if the salvo was long presumably that one shell would have had an angle of fall different to the others? How far long or short would they have had to be? A question Mr Jurens would be able to help me out with!"

I can try. Depending upon quibbles in range the angle of fall was probably nominally around 15 degrees. (The angle of fall as measured on PoW was, as I recall eight or ten degrees, but that of course also includes list/heel at the time of impact, which could easily move things a few degrees either way, and the measurements were probably fairly rough and ready to begin with...) The cotangent of 15 degrees is roughly 3.7, which means that the range changes 3.7 times faster than the height does, so one shot striking say 30 meters higher than another would be landing about 3. x 3.7 = 111 (say 110) meters farther downrange.

The rate of change of angle of fall at these ranges is fairly small, increasing at the rate of about 1.33 degrees per kilometer, so a difference in range of 110 meters would amount to a change in angle of fall of only about .11*1.33 = 0.146 degrees, which all things considered is entirely negligible. In other words, in this particular situation, the trajectories of projectiles falling in a typical salvo pattern can be considered to be virtually parallel.

Hope this helps...

Bill Jurens

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Re: PoW's gunnery VS BSM's gunnery

Post by HMSVF » Fri Apr 05, 2019 5:05 pm

Bill Jurens wrote:
Fri Apr 05, 2019 4:15 pm
HMSVF wrote:

"Are the shell splashes short or long? If they are short doesn't that mean that the shell which went through the compass platform had a completely different angle of fall than the rest of the salvo, I mean the compass platform was way up high in the bridge structure, I'd imagine it didn't come down at an angle of 45 degrees, presumably it would fall at I dunno, 10 to 20 ?Ditto if the salvo was long presumably that one shell would have had an angle of fall different to the others? How far long or short would they have had to be? A question Mr Jurens would be able to help me out with!"

I can try. Depending upon quibbles in range the angle of fall was probably nominally around 15 degrees. (The angle of fall as measured on PoW was, as I recall eight or ten degrees, but that of course also includes list/heel at the time of impact, which could easily move things a few degrees either way, and the measurements were probably fairly rough and ready to begin with...) The cotangent of 15 degrees is roughly 3.7, which means that the range changes 3.7 times faster than the height does, so one shot striking say 30 meters higher than another would be landing about 3. x 3.7 = 111 (say 110) meters farther downrange.

The rate of change of angle of fall at these ranges is fairly small, increasing at the rate of about 1.33 degrees per kilometer, so a difference in range of 110 meters would amount to a change in angle of fall of only about .11*1.33 = 0.146 degrees, which all things considered is entirely negligible. In other words, in this particular situation, the trajectories of projectiles falling in a typical salvo pattern can be considered to be virtually parallel.

Hope this helps...

Bill Jurens

Thanks Bill,

Great explanation !

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Re: PoW's gunnery VS BSM's gunnery

Post by HMSVF » Fri Apr 05, 2019 6:23 pm

HMSVF wrote:
Fri Apr 05, 2019 5:05 pm
Bill Jurens wrote:
Fri Apr 05, 2019 4:15 pm
HMSVF wrote:

"Are the shell splashes short or long? If they are short doesn't that mean that the shell which went through the compass platform had a completely different angle of fall than the rest of the salvo, I mean the compass platform was way up high in the bridge structure, I'd imagine it didn't come down at an angle of 45 degrees, presumably it would fall at I dunno, 10 to 20 ?Ditto if the salvo was long presumably that one shell would have had an angle of fall different to the others? How far long or short would they have had to be? A question Mr Jurens would be able to help me out with!"

I can try. Depending upon quibbles in range the angle of fall was probably nominally around 15 degrees. (The angle of fall as measured on PoW was, as I recall eight or ten degrees, but that of course also includes list/heel at the time of impact, which could easily move things a few degrees either way, and the measurements were probably fairly rough and ready to begin with...) The cotangent of 15 degrees is roughly 3.7, which means that the range changes 3.7 times faster than the height does, so one shot striking say 30 meters higher than another would be landing about 3. x 3.7 = 111 (say 110) meters farther downrange.

The rate of change of angle of fall at these ranges is fairly small, increasing at the rate of about 1.33 degrees per kilometer, so a difference in range of 110 meters would amount to a change in angle of fall of only about .11*1.33 = 0.146 degrees, which all things considered is entirely negligible. In other words, in this particular situation, the trajectories of projectiles falling in a typical salvo pattern can be considered to be virtually parallel.

Hope this helps...

Bill Jurens

Thanks Bill,

Great explanation !

One last question if I may!? Would a say a 110 metre difference still constitute a straddle ? Or would the gunnery officer recalculate for 100 metres down?


Thanks in advance


HMSVF

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Re: PoW's gunnery VS BSM's gunnery

Post by dunmunro » Fri Apr 05, 2019 6:29 pm

HMSVF wrote:
Fri Apr 05, 2019 11:23 am
Alberto Virtuani wrote:
Wed Apr 03, 2019 8:24 am
Hello everybody,

Dunmunro wrote: "GO McMullen did not have access to Bismarck's GAR and so couldn't compile comparable data for Bismarck...and unfortunately neither can we."
...but very "fortunately" we have the precise number of shells fired, thus we can simulate any number of ordered shots / semi-salvo and get to the same identical conclusions: PoW RoF was in any case comparable to Bismarck's (viewtopic.php?f=1&t=8491&start=315#p82614). Sorry for that.


Bye, Alberto

Morning all.


A quick question. If Hood was sunk at 06:00 hrs and the compass hit was at 06:00 and 50 seconds that means that Schneider was able to switch targets, fire and hit within a matter of seconds?

Are the shell splashes short or long? If they are short doesn't that mean that the shell which went through the compass platform had a completely different angle of fall than the rest of the salvo, I mean the compass platform was way up high in the bridge structure, I'd imagine it didn't come down at an angle of 45 degrees, presumably it would fall at I dunno, 10 to 20 ?Ditto if the salvo was long presumably that one shell would have had an angle of fall different to the others? How far long or short would they have had to be? A question Mr Jurens would be able to help me out with!



So sharp shooting Schneider was able to switch targets and hit a matter of seconds and would have been bang on the money for following salvos? No wonder Leach turned away. He would have suffered a right kicking.




Best wishes!

HMSVF



Sorry, additional!


The shell that struck the compass platform didn't explode as far as I'm aware ? So there must have been an entry and exit hole? Unless the shell tumbled/ricocheted it would have gone straight through, so there would have been an angle of decent? Wouldn't the rest of the shells (if high landed a fair distance behind POW?

Always willing to learn !


Best wishes HMSVF
A&A claim that Bismarck's RoF was constant throughout the action. If this is so, and Bismarck changed targets at 0600:30 and began scoring hits at ~0601 than that means that Bismarck was scoring hits at the rate of about 3/min on PoW whilst receiving none in return during that time frame, and it means that Bismarck scored those 3 hits by firing ~3 salvos and ~12 x 38cm rnds. This gives us an idea of how many hits PoW was likely to receive if she maintained course to shoot it out with Bismarck, and it ignores the fact that PE also scored 4 hits in this time frame, so in the space of a couple of minutes PoW received 7 hits and scored none in return. Additionally, Bismarck and PE's secondary armament was also within effective range whilst PoW's had ceased fire due to damage to her secondary gun directors.

However, I don't believe that Hood blew up at 0600 but rather at ~0558 and thus Bismarck had more time on PoW prior to her turning to open the range.

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Re: PoW's gunnery VS BSM's gunnery

Post by Bill Jurens » Fri Apr 05, 2019 8:14 pm

HMSVF wrote:

"One last question if I may!? Would a say a 110 metre difference still constitute a straddle ? Or would the gunnery officer recalculate for 100 metres down?"

Making some reasonable assumptions would suggest that Bismarck's expected average pattern size at the ranges we are talking about would have been in the vicinity of 200 meters. Assuming the range difference between PoW and Hood to have been around 500 yards, the switch would have been easy; you can see that the enemy, i.e. PoW is turning towards you, so bearing rate would go down a bit, so a quick estimate would be 'down 400, left 5 mils. That would put you more or less right on the money, at least in range. The danger space at this range, depending upon how 'high' the effective target is, is around 260 meters, so you are only a couple of patterns out.

Had PoW turned away to pass downrange of Hood, there probably would have been severe criticism about breaking off the engagement too soon, or complaints about hiding behind the smokescreen. Of course keeping on course and hitting Hood was not a good idea either. The other alternative, turning towards the enemy and passing in front of a ship just fatally hit really puts you in a shooting gallery, but 'going behind', though considerably safer, represents an alternative that I really don't think Leach even considered. He was unlikely to have been conservative in combat; Royal Navy doctrine -- the "Nelson Approach" tended to favor a more assertive approach in action, and I suspect commanders who were not rather aggressive and assertive in nature would have been weeded-out, or if intelligent enough retained and transferred to 'desk jobs' earlier on in their careers, rather than been given combat commands.

Bill Jurens.

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Re: PoW's gunnery VS BSM's gunnery

Post by Alberto Virtuani » Fri Apr 05, 2019 8:27 pm

Hello everybody,
Dunmunro wrote: "that means that Bismarck was scoring hits at the rate of about 3/min on PoW"
Wrong.
Bismarck scored hits on PoW between minute 6:00 and minute 6:02, therefore 1.5 hit per minute, that is very high, but absolutely not impossible in such a situation, where the range was becoming very effective.
PoW couldn't hit in return, at such favorable range, due to the avoiding maneuvers and then to the hard turn away. Had she kept engaging assuming a steady course at 6:02, she would have probably scored many hits as well, after having possibly received one more.
At 6:03 she would have been in a very good tactical situation with the false "torpedo alarm" that forced the German ships to turn hard.


Bill Jurens wrote: " the angle of fall was probably nominally around 15 degrees."
Where is this value coming from, please ? AFAIK, the German 15" gun had a shell angle of fall of 10°-11°at 15000 meters.
This would match very well with the PoW damage report, that estimated 9°.
PoW hit #1.jpg
PoW hit #1.jpg (12.68 KiB) Viewed 373 times




However,
despite all the above items being extremely interesting, I see that nobody here intends to acknowledge the proposed comparison between PoW and BS average RoF, based on facts and not on speculations or hypothetical scenarios.
Everybody seem more interested to discuss qualitative aspects... :think:

Fine, for me the discussion is over then. I have published the relevant figures and nobody has been able to counter a single item from 1) to 4), therefore I give them as accepted by everybody (the rant "no" without any reasoning behind or the claim that "assumptions" are wrong without any proposed alternative assumption count zero...).
download/file.php?id=3457


Bye, Alberto
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Re: PoW's gunnery VS BSM's gunnery

Post by dunmunro » Fri Apr 05, 2019 9:00 pm

Alberto Virtuani wrote:
Fri Apr 05, 2019 8:27 pm
Hello everybody,
Dunmunro wrote: "that means that Bismarck was scoring hits at the rate of about 3/min on PoW"
Wrong.
Bismarck scored hits between minute 6:00 and minute 6:02, therefore 1.5 hit per minute, that is very high, but absolutely not impossible in such a situation, where the range was becoming very effective.
PoW couldn't hit in return due to the avoiding maneuvers and then to the hard turn away. Had she kept engaging on a steady course she would have probably scored hits as well immediately after 6:02. At 6:03 she would have been in a very good situation with the false "torpedo alarm" that forced the German ships to turn hard.
You stated that the first 38cm hit on PoW was at "...6:00:50..." not 0600, and if the last hits were scored at ~0602 then the hits were scored within ~70 seconds.

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Re: PoW's gunnery VS BSM's gunnery

Post by Alberto Virtuani » Fri Apr 05, 2019 9:06 pm

Hello everybody...
Dunmunro wrote: "the hits were scored within ~70 seconds"
...and mathematically 3 hits in 70 seconds (#1 at second 0, #2 at second 35 and #3 at second 70) are an average of (less than) 1.5 / minute or, if you count the first one, less than 2, not 3 / minute for sure....even assuming the last one arrived at 6:02:00 exactly

Please, acknowledge the average RoFs (points 1,2,3 and 4 download/file.php?id=3457) instead of trying to create new (wrong) figures.


Bye, Alberto
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Re: PoW's gunnery VS BSM's gunnery

Post by Bill Jurens » Fri Apr 05, 2019 11:26 pm

With respect to some of my previous analysis Mr. Virtuani wrote:

Where is this value coming from, please ? AFAIK, the German 15" gun had a shell angle of fall of 10°-11°at 15000 meters.
This would match very well with the PoW damage report, that estimated 9°.


My statement was "Depending upon quibbles in range the angle of fall was probably nominally around 15 degrees". I think that my statement is sufficiently qualified -- it was written that way on purpose -- to indicate that it was just an estimate to be used in a quick 'back of the envelope' type calculation. From GKDOS100 the angle of fall at 15,000 meters is about 10.6 degrees. Insofar as we really don't know the range that accurately, I took a 15 degree figure as 'close enough' to illustrate the point. The results won't change much, and in fact make the change from one target to the other easier as the angle of fall decreases, to the point where one is really just 'shooting through' Prince of Wales as she passes in front of Hood.

Mr. Virtuani also wrote:

"I have published the relevant figures and nobody has been able to counter a single item from 1) to 4), therefore I give them as accepted by everybody (the rant "no" without any reasoning behind or the claim that "assumptions" are wrong without any proposed alternative assumption count zero...)." [underlining added by myself for emphasis W.J.J.]


In my opinion, the underlined statement is not justifiable at all. Lack of a response, or an inability to formulate an alternative scenario does not constitute consensus. I don't agree with the statements (1 to 4 or whatever) made at all. One can know what's wrong, without knowing what's right. I may know, for example, that a statement that the Prime Minister of England was born in 1883 must be incorrect, but the quality of that judgment is not decreased by the fact that I do not have -- except in the broadest terms -- a better alternative date at hand.

My sense of the admittedly somewhat informal survey recently done on the supposed viability of the track charts and the subsequent hypothesis that these can be used to bolster an argument that British leadership was in some way significantly deficient at Denmark Strait, would seem to suggest that few if any participants in this forum, with the possible exception of yourself and Mr. Bonomi, actually strongly support your conclusions and/or methodolgy.

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Re: PoW's gunnery VS BSM's gunnery

Post by northcape » Sat Apr 06, 2019 12:18 am

Bill Jurens wrote:
Fri Apr 05, 2019 11:26 pm




"I have published the relevant figures and nobody has been able to counter a single item from 1) to 4), therefore I give them as accepted by everybody (the rant "no" without any reasoning behind or the claim that "assumptions" are wrong without any proposed alternative assumption count zero...)." [underlining added by myself for emphasis W.J.J.]


In my opinion, the underlined statement is not justifiable at all. Lack of a response, or an inability to formulate an alternative scenario does not constitute consensus. I don't agree with the statements (1 to 4 or whatever) made at all. One can know what's wrong, without knowing what's right. I may know, for example, that a statement that the Prime Minister of England was born in 1883 must be incorrect, but the quality of that judgment is not decreased by the fact that I do not have -- except in the broadest terms -- a better alternative date at hand.
Mr. Jurens,

the (needless to say 100% correct) statement of yours has been made repeatedly by many different people. Like mentioned before, in my view it simply shows that it is absolutely futile to try to enter a discussion [descriptor redacted WJJ], so the only response can be none at all. What we are experiencing here lately takes us to so far unseen levels of absurdity and Orwellian double-think at its finest ("nobody agrees with me, so I take this that everybody approves what I'm saying!")

Like you suggested before, I think it is the best to lock this thread. Mr. V. will of course have the last post, but this is completely fine. I think this forum can only approve if the majority, who in my view still shows rational behaviour and civil manners, will now and in future simply and totally ignore [material redacted WJJ] their opponents, as they have no other platform where they can make themselves noticed.

[I have redacted commentary characterizing some individuals as 'flat-earth scientists'. WJJ.]

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Re: PoW's gunnery VS BSM's gunnery

Post by dunmunro » Sat Apr 06, 2019 12:23 am

Alberto Virtuani wrote:
Fri Apr 05, 2019 9:06 pm
Hello everybody...
Dunmunro wrote: "the hits were scored within ~70 seconds"
...and mathematically 3 hits in 70 seconds (#1 at second 0, #2 at second 35 and #3 at second 70) are an average of (less than) 1.5 / minute or, if you count the first one, less than 2, not 3 / minute for sure....even assuming the last one arrived at 6:02:00 exactly

Please, acknowledge the average RoFs (points 1,2,3 and 4 download/file.php?id=3457) instead of trying to create new (wrong) figures.


Bye, Alberto
3 hits in 70 secs = 2.6 hits/min

Using A&A's methodology and timing:

Bismarck's output = 93 x 38cm rnds (upon which we mostly agree)

~40 x 38cm are fired at Hood = 1 or more hits

~13 are fired at PoW from ~0600:50 - 0603:00 and and score 3 hits

~40 are fired from 0603-0609 (6 minutes) and score no hits.

The statistical improbability of so small a number of rounds fired to score 3 hits stands out, but so does the accuracy of Bismarck's fire if the numbers are correct. In the same or similar time frame PE has scored 4 hits.

It would only take 2 or 3 more minutes of hits (10-20 more) at that rate before PoW's 14in FC system is disabled and/or one or more turrets are destroyed along with a high probability of machinery damage because PoW is outside her immune zone. PoW is then crippled and destroyed by Bismarck and PE's torpedoes. Is it any wonder that Leach turned to open the range?




In another thread I looked at PE's and Bismarck's RoF as carefully as I could:


This is from the Baron:
Lindemann's permission for us to open fire was immediately followed by our first heavy salvo. The Bismarck was in action, and the rumble of her gunfire could be heard as far away as Reykjavik, the capital of Iceland.* I
heard Schneider order the first salvo and heard his observation on the fall of the shot, "short." He corrected the range and deflection, then ordered a 400-meter bracket.* The long salvo he described as "over," the base salvo
as "straddling," and immediately ordered, "Full salvos good rapid." He had thus laid his battery squarely on target at the very outset of the engagement.
So we have the order for full salvos and rapid fire (which implies that more deliberate fire was used elsewhere) and here we can confirm that via
Jasper:
The bearing range-finding station reported 2 contacts off the right bow bearing 20° [2 Dez.J at 25
knots, distance 210 hectometers [21,000 meters]. | received "permission to fire" from the bridge
at 0455 hours and immediately commenced firing a full salvo at 202 hectometers [20,200
meters]. The full [8-gun) salvo was fired using nose fuzed rounds which were stored behind the
gun bairels as ready-to-use ammunition. The observable impacts [shell splashes] could not be
ascribed with certainty as belonging to our own [shells] because of [key punch] perforation
failures in the firing calculator [and thus no range correction report could be made]. Therefore, I
repeated [firing] a full salvo, which turned out to be observable and formed a straddle ladder of
which I could only observe two brief impacts from the lower limiting [rounds of the] salvo, while
the higher and middle [rounds] had to be called questionably too far. The distant impacts were
not visible, since they were concealed by the target. By contrast, [after firing] the bracketing
group an extraordinarily bright fire flash appeared on the enemy ship's aft section at the level of
the aft mast. The fire developed on the portside of the opponent, since the superstructures
stood out as sharp sihouettes. Immediately thereafter | received the order from the ship's
command to "Change target to the left" toward the second opponent [the Prince of Wales],
whereby the fire of "Bismarck" and "Prinz Eugen" now crossed. I was unable to observe
"Bismarck's" decisive savo because I was no longer in a position to do so. | ordered the
targeting officer [larget designator] to acquire the second target and thus lost the first [targel]
from the [range finder's] visual field of action. Consequently, | did not perceive the detonation of
the first target [Hood].

As was the case earlier, I commenced the second firing with a full salvo followed by a ranging
group [straddle ladder] which zeroed me in as of 0559. Firing for effect was then initiated. The
distance at that time was 160-170 hectometers [16,000-17,000 meters]. During the completion
of ranging fire's effectiveness, | observed two well-placed simultaneous portside rikss which
again were fired by the secondary artillery of the "Bismarck". At around the 8" salvo, the
opponent turned at first hard toward (us).
So Jasper states that he ordered 24 rounds ( 13% of requested output) to be fired in only 3 salvos, all near the first 2 minutes of the action. He seems to imply the use of full salvos after that as well. Anyways, it is clear that the KM would switch between full and half salvos during daylight actions. BWOC, RN battleships used half salvos exclusively during daylight, unless there were insufficient numbers of guns available to fire in which case full salvos might be used as a temporary expedient.

We can see from this that KM RoF would vary considerably depending on the situation and FC solution.

I disagree with A&A on their contention about a metronomic RoF from PE and Bismarck because it is not supported by the historical record, additionally their contention that Bismarck suffered a large loss of 38cm output has absolutely non basis in the historical record nor is their any evidence of loss of output in the photographic record, or even in post war memoirs or war time interrogation or debriefing reports.

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