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Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 8:55 am
by alecsandros
Alberto Virtuani wrote:
Again, IMHO the explanation for BS slow firing is, as Tommy confirmed, that no ship fires at her theoretical RoF when in a real combat situation.
But what about the film which shows us something else ?

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 10:03 am
by Alberto Virtuani
@Alecsandros:
Hi Alec, I have edited my previous post to cover your question while you were asking it...... sorry, my mistake.
I wrote: "Regarding the film (and assuming all guns in a turret are actually fired....), it just mean that after the turn they had all guns already loaded and used a "gabelgruppe" fast firing method the get the range again (forgetting precision), but when in effective fire mode this rate could not be maintained (for Schneider's choice or other reasons, as Tommy explained)."
Bye, Alberto

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 10:09 am
by alecsandros
Alberto Virtuani wrote:@Alecsandros:
Hi Alec, I have edited my previous post to cover your question while you were asking it...... sorry, my mistake.
I wrote: "Regarding the film (and assuming all guns in a turret are actually fired....), it just mean that after the turn they had all guns already loaded and used a "gabelgruppe" fast firing method the get the range again (forgetting precision), but when in effective fire mode this rate could not be maintained (for Schneider's choice or other reasons, as Tommy explained)."
Bye, Alberto
... 20 shots ordered in 55 seconds... means in the rest of the battle (785 seconds) they are left with 84 shots ordered (or 92).

This means 0,80 to 0,88 shots ordered per minute per gun. Or one shot ordered every ~ 66 to 72 seconds.

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 1:30 pm
by Antonio Bonomi
Hello everybody,

@ Alecsandros,

I see your concerns.

What I think currently is that at the beginning of the film as well as into the first photo after the second turn, ... Nh 69729 ...

http://www.history.navy.mil/our-collect ... 69729.html

... we can see the Gabelgruppe being fired, ... in a faster way if compared to the average Bismarck rate of fire thru all the engagement.

This is based not only on the total number of shells fired ( 93 ) and the other data we have ( 40 on 5 minutes to Hood ).

What I am saying is that if you continue the film after the initial " fast " sequence, you will see that the groups will slow down firing sincerely ... and A+B will fire ( on photo Nh 69727 ) only after a longer time at the end of the second sequence.

http://www.history.navy.mil/our-collect ... 69727.html

So after the 2 turns, ... apparently no Vollsalve ... but only the Gabelgruppe at " fast rate " ... and than fire for effect at the average " slow " rate ... but not at the maximum rate of fire.

Opinions are welcome ...

Bye Antonio :D

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 1:48 pm
by alecsandros
Antonio Bonomi wrote:

So after the 2 turns, ... apparently no Vollsalve ... but only the Gabelgruppe at " fast rate " ... and than fire for effect at the average " slow " rate ... but not at the maximum rate of fire.
... IF we exclude the salvos fired in the film, we remain with a rate of fire of 66 to 72 seconds per salvo. That's slower than Iowa firing against Nowaki at 32km.

Maybe that's it - and we should take it as it is. But I am somewhat intrigued to see ~70 seconds intervals in a fight to the death, coming from a machine which could fire at 20 seconds intervals (and is filmed firing at 23sec).

All the best,

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 3:31 pm
by Steve Crandell
alecsandros wrote: The movie shows much rapid firing intervals ... I see 23sec once, 25 sec once, 31 seconds once... NOt 60... NOt 70...
... and even that is not 20 seconds per salvo which is the number you often use when comparing Bismarck to other battleships.

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 4:39 pm
by alecsandros
Steve Crandell wrote:
alecsandros wrote: The movie shows much rapid firing intervals ... I see 23sec once, 25 sec once, 31 seconds once... NOt 60... NOt 70...
... and even that is not 20 seconds per salvo which is the number you often use when comparing Bismarck to other battleships.
... In AVKS combat trials, reloading cycle appears to be as low as 19 seconds (3.125 shells transported to each gun on average per minute).

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 7:06 pm
by ede144
The loading cycle must technically faster than fastest possible firing sequence. Especially with the German firing techniques. Please note that neither turret direction nor gun elevation was at firing position during loading. Both moved after firing command was initiated. Both guns elevated individually and fired independent when reached the individual calculated firing angle. A delay coil between the guns was not necessary.

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 7:47 pm
by tommy303
Both guns elevated individually and fired independent when reached the individual calculated firing angle. A delay coil between the guns was not necessary.
This would be true when the guns were set to fire an an arbitrary angle as the ship turned or if rolling heavily, and at times when the firing was done at the gunnery Rechenstelle through the Rw--HW Geber and the Krag apparatus at each gun, but when firing from director, the Rw-Hw Geber kept the guns on target and the director layer fired by pressing a firing key or by means of blowing into a pneumatic tube held in his mouth. In any event, delay coils were introduced into the Kriegsmarine in 1939/40.

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 8:29 pm
by Steve Crandell
alecsandros wrote:
Steve Crandell wrote:
alecsandros wrote: The movie shows much rapid firing intervals ... I see 23sec once, 25 sec once, 31 seconds once... NOt 60... NOt 70...
... and even that is not 20 seconds per salvo which is the number you often use when comparing Bismarck to other battleships.
... In AVKS combat trials, reloading cycle appears to be as low as 19 seconds (3.125 shells transported to each gun on average per minute).
My point was that in a real battle with the ship's survival at stake, the average rate of fire was not 3.125 shells per gun per minute, and it never would be. A lot of people use that reloading cycle to show how Bismarck's firepower was much greater than all other battleships, and in the actual case it was simply not true.

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 8:31 pm
by alecsandros
Steve Crandell wrote: My point was that in a real battle with the ship's survival at stake, the average rate of fire was not 3.125 shells per gun per minute, and it never would be. A lot of people use that reloading cycle to show how Bismarck's firepower was much greater than all other battleships, and in the actual case it was simply not true.
I know this argument,
And it makes sense, most of the time.

But here, as I have shown above, we have a 55 seconds footage for 20 x 380mm guns fired. That is 2.73 shots per minute per gun.

Re: Bismarck firing procedures at DS

Posted: Wed Feb 24, 2016 8:38 pm
by Steve Crandell
alecsandros wrote:
Steve Crandell wrote: My point was that in a real battle with the ship's survival at stake, the average rate of fire was not 3.125 shells per gun per minute, and it never would be. A lot of people use that reloading cycle to show how Bismarck's firepower was much greater than all other battleships, and in the actual case it was simply not true.
I know this argument,
And it makes sense, most of the time.

But here, as I have shown above, we have a 55 seconds footage for 20 x 380mm guns fired. That is 2.73 shots per minute per gun.
Right. For 55 seconds. We know it was possible mechanically. That does not mean it is realistic to assume 3.125 shells per minute for a battle when comparing two ships' firepower.

Re: Bismarck firing procedures at DS

Posted: Sat Feb 27, 2016 3:41 pm
by Byron Angel
Assuming 5 x 4 gun salvoes, it should be kept in mind that Bismarck's main battery started in loaded condition; hence the loading cycles for the two first two salvoes are not included in the elapsed time of 55 seconds. The film clock (IIUC) begins ticking only with the first actual salvo discharge. If memory serves, the engagement consisted of an initial forking group of two salvoes spotted over, a second two salvo forking group that bracketed the target, and a fifth salvo that straddled Hood. That suggests only two reloading cycles per gun (second forking group + fifth salvo) and two fall of shot spots (first forking group + second forking group).

FWIW - off the top of my head (always dangerous territory).

B

Re: Bismarck firing procedures at DS

Posted: Sat Feb 27, 2016 8:34 pm
by alecsandros
Hi Byron,
Well the initial salvos of any battleship are loaded before the battle starts... in 90% of the cases. If you want you can clock the salvos in the film and see what intervals of fire are filmed (to see actual reloading cycles). I got 23, 25 and 31 seconds for main battery, with in-betweens of 10, 10, 11 seconds salvos from the secondary artillery.

The film is probably showing "battle time" around 6:02 - 6:03, after Hood was destroyed.

Several aspects should be adressed, IMHO: is the 55seconds piece non-altered, i.e. modified; is the transfer from analog to digital film "perfect", i.e. are we seeing real-time footage, or is it somewhat accelerated or slowed down from the original; if the film piece turns out to be non-altered and real time, why oh why did the Bismarck expend so few shells as reported by Luetjens to Group North...?

Re: Bismarck firing procedures at DS

Posted: Sun Feb 28, 2016 4:40 pm
by Byron Angel
Fair comment, Alecs. Was just pointing out that, if starting from a loaded condition, three salvo cycles (2x ranging forks + 1x salvo) would be achievable within approximately 55 seconds without extraordinary measures.

B