KGV Class 14-in Turret Problems

[dunmunro]

Rodney opened fire at 8:47, KGV at 8:48, at 8:53 Rodney turned to open her A arcs, KGV did not open her A arcs until 9:10. Therefore, Rodney had far more oportunity to fire more rounds in the first minutes of the action than KGV, and this is when both KGV and Rodney had their highest output. KGV ceased fire for some time as smoke and wind obscured the target, around 9:20 and KGV had a much poorer view of the target than Rodney for most of the action.

In fact if we replace KGV with a doppelganger Rodney, we would discover that our duplicate Rodney would have fired far fewer rounds during the engagement than the actual Rodney because she simply had less opportunity to do so.

Even if KGV had only had 5 guns firing during the entire engagement, she could have fired more rounds than she actually did, if she would have had a clear line of sight to the target for the entire 90 minutes of the engagement. KGV fired fewer round because she had less opportunity to fire at Bismarck, and this explains her much lower secondary output during the engagement.

Had KGV engaged Bismarck by herself, her output would have greater and her accuracy better, since she would be the only BB engaging the target, and Bismarck would probably have sunk just as quickly.

cheers

Duncan

[Bgile]

Duncan,

You can color this any way you want, but whatever KGVs output was, it should have been higher but for the failure of her 4-gun turrets. If she had had more opportunity to fire, the failures would have been more significant.

I’ve done a bit of refresher reading on NAVWEAPS, a site which you have quoted from. I note that you were rather selective when quoting the problems Rodney had during the Bismarck engagement. Here is a quote from the beginning paragraphs in that same section, after explaining the guns on Rodney class were far from trouble free:

“Nevertheless, it should be noted that these guns on Rodney proved to be far more reliable than did the new 14" (35.6 cm) guns on HMS King George V and HMS Prince of Wales during the two battles with the German battleship Bismarck.”

Please note also that the practical rate of fire with no problems for Rodney was much slower than that of KGV, making KGV’s comparatively reduced output more glaring.

[Nellie]

Duncan, you get me wrong! This is not about the rate of fire KGV produced compared to how high it could have been if she had gone on maximum output the hole battle, what i mean is how many misfires they were compared to how many shells who really leaved the turrets. In what way the gunnerycrew choosed to open fire during the battle is out of point here! (With misfires i mean shells who had leaved the shellrom but during some circumstances not could be fired.) With the hole A-turret out of action in half an hour you can only estimate who many shells there were missed to be fired. We can calculate on this for a long time but i will never think that when four main guns at the same time is out of action in half an our is normal for a WWII battleship.

[dunmunro]

Duncan,

“Nevertheless, it should be noted that these guns on Rodney proved to be far more reliable than did the new 14" (35.6 cm) guns on HMS King George V and HMS Prince of Wales during the two battles with the German battleship Bismarck.”

Please note also that the practical rate of fire with no problems for Rodney was much slower than that of KGV, making KGV’s comparatively reduced output more glaring.

I'm not interested in Navweapon's or any one else's editorializing, and neither should you be. Decades of misunderstanding and misconception have arisen because of statements like the one you quote from Navweapons, but statements which do not bear up to close scrutiny.

How do you explain the fact that 8 5.25" (per side) guns from KGV, guns with a higher RoF than the 6 6" guns on Rodney, fired fewer rounds? Maybe KGV's "defective turret disease" is catching? KGV, was farther from the target, and had poorer visibility as a result which made getting a firing solution much more difficult, in the gale force winds and due to Rodney's gunsmoke. If you look at the map you can see very clearly how Rodney was positioned such that her firing helped obscure the target for KGV, for much of the action. Tovey made a deliberate decision to place KGV well away from Rodney, but in doing so he placed KGV in a far less advantageous position for effective gunnery.

cheers

Duncan

[Bgile]

Duncan,

I've read the report on the Idaho shoot but I can't find it right now. Would you mind giving us a link to it?

How many of Idaho's six guns involved in the shoot were out of action at the end? KGV had 5 guns out of action (in addition to the turret problems) at the end of her engagement with Bismarck.

[dunmunro]

We can calculate on this for a long time but i will never think that when four main guns at the same time is out of action in half an our is normal for a WWII battleship.

Nellie, KGV had a turret jam because a shell rolled out of place and lodged in a position to block the revolving structure of the turret. This happened when KGV made a high speed turn, and in the gale force seas, this produced excessive motion in the turret. This really had nothing to do with the mechanical reliability of the turret.

cheers

Duncan

[dunmunro]

Duncan,

I've read the report on the Idaho shoot but I can't find it right now. Would you mind giving us a link to it?

How many of Idaho's six guns involved in the shoot were out of action at the end? KGV had 5 guns out of action (in addition to the turret problems) at the end of her engagement with Bismarck.

most of it is reproduced in the following thread:

http://www.bobhenneman.info/forum/viewt ... c&start=30

KGV had 5 guns out of action at the end, but all turrets were operational. Many of the gun failures were due to misfires, and they were giving the guns a chance to cool prior to unloading them. As you will read Idaho had 13 misfires during the shoot.

cheers

Duncan

[Bgile]

How do you explain the fact that 8 5.25" (per side) guns from KGV, guns with a higher RoF than the 6 6" guns on Rodney, fired fewer rounds? Maybe KGV's "defective turret disease" is catching? KGV, was farther from the target, and had poorer visibility as a result which made getting a firing solution much more difficult, in the gale force winds and due to Rodney's gunsmoke. If you look at the map you can see very clearly how Rodney was positioned such that her firing helped obscure the target for KGV, for much of the action. Tovey made a deliberate decision to place KGV well away from Rodney, but in doing so he placed KGV in a far less advantageous position for effective gunnery.

cheers

Duncan

There could be any number of reasons for ordering the secondary battery to cease firing, but here are a few off the top of my head:

1. Target obscured by smoke. KGV used radar to assist firing the main guns, but that wouldn't have been possible in the case of the secondary battery in 1941.

2. Inabilility to spot splashes and correct fire due to interference. Rodney's 6" and cruiser 8" fire would all have been larger splashes, making it very difficult to spot for KGV's secondary battery.

3. Arcs of fire closed. During the entire approach phase, KGVs secondary battery probably wouldn't have fired at all, whereas Rodney's secondary battery would be able to fire and spot it's larger splashes out to 18 kyds or so.

4. Target silenced. No point in firing 5.25" at all once the target has been silenced.

[Bgile]

KGV had 5 guns out of action at the end, but all turrets were operational. Many of the gun failures were due to misfires, and they were giving the guns a chance to cool prior to unloading them. As you will read Idaho had 13 misfires during the shoot.

cheers

Duncan

Your link is to a discussion forum, not the buweaps report of the shoot. Whe n I have more time I will read that thread, but are you saying the report is somewhere in that thread?

There is a difference between a misfire and a gun out of action. 5 of KGVs guns were out of action at the end of the engagement. How many of Idahos were?

Why do you think this popular conception of an unusual number of problems in the KGV quads came from? A whole bunch of people who hate the British? What?

[dunmunro]

KGV had 5 guns out of action at the end, but all turrets were operational. Many of the gun failures were due to misfires, and they were giving the guns a chance to cool prior to unloading them. As you will read Idaho had 13 misfires during the shoot.

cheers

Duncan

Your link is to a discussion forum, not the buweaps report of the shoot. Whe n I have more time I will read that thread, but are you saying the report is somewhere in that thread?

There is a difference between a misfire and a gun out of action. 5 of KGVs guns were out of action at the end of the engagement. How many of Idahos were?

Why do you think this popular conception of an unusual number of problems in the KGV quads came from? A whole bunch of people who hate the British? What?

Yes, it is in that thread, on page 4, IIRC.

A misfire is a gun out of action, and it will remain out of action until it is safe to clear the breech. Idaho's last 8 salvos were one gun salvos (with one exception) with a average of 2 minutes between them. This might indicate that some guns were not considered safe to fire, but maybe not.

As I've pointed out repeatedly, the KGV and DoY fought the two longest actions on record. The longer an action, the higher the probability that the availability rate will fall. Rodney's final broadsides achieved a 62% availability rate, while Idaho averaged 64% over her 156 salvos, in calm weather. If we subtract Idaho's last 8 salvos from the calculation we get a 67% availability rate. What matters, at the end of the day, is what is the average availability rate going to be, not what is it at any particular moment during the action.

I think the misconception arose because there was no attempt to statistically analyse these actions, to see what the average availability rate is likely to be, and whether the KGVs were more likely to be worse than the average. I don't think this resulted from anti-Brit bias but from a misreading of data by all parties concerned, including the RN. There is also a tendency to lump the PoW''s results into the mix, when, clearly, she was not combat ready.

http://www.battleshipbismarck.com/bisma ... battle.php

you can see on the above battle maps how much closer Rodney was to Bismarck for most of the action.

cheers

Duncan

[dunmunro]

[

There could be any number of reasons for ordering the secondary battery to cease firing, but here are a few off the top of my head:
.

1) KGV's radar did not have blind fire capability, if the target is obscured the FC system cannot generate a firing solution. KGV's secondary directors have almost the same vanatge point as her main directors.
2) This also applies to the 14" guns, and smoke from KGV's guns, funnels and Rodney's own guns and funnel and the Bismarck's own fires made obtaining a FC solution very difficult for KGV.

3) KGV's forward pair of 5.25" turrets always had a potential view but KGV's secondary guns were always hampered by the longer range to the target.

4) Once the target was silenced there was no overiding imperative to quickly bring KGV's main guns back on line.

Here is an interesting analysis of the first 30 minutes of the battle, when we have a good idea of the actual RoF of both ships, and it is unlikely that there were major failures on either ship at this time:

KGV

30mins @ 1.7 salvos minute = 51

34 x 3 = 102 (open fire at 8:48)
17 x 5 = 85 (A arc opened at 9:10)
----
187

Rodney

31 minutes @ 1.6 salvos minute = 49.6

11 x 3 = 30 (open fire at 8:47)
39 x 4.5 = 175 (A arc opened at 8:53)
------
208

187/208 = .899 ( Note that the ratio at this point is the same as at the end of the engagement)

there is some ambiguity as to how many salvos KGV fired before the turret jam at 9:20. so I left it at 51, however, Navweapons states that A turret has fired 23 RPG, which would imply 46 salvos, more salvos tends to favour KGV in this analysis (also note that KGV fired 23% of her ammo from the forward turrets without problems. and may have achieved a 100% availability rate. although this is statistically unlikely)
So at 30 minutes into the action Rodney had the same ratio of rounds fired as at the end, indicating that the availabilty rate of both BBs must have been very similar.

cheers

Duncan

[paul mercer]

A few questions, if one has a misfire in a gun that uses cordite for it's charge (as oppose to a complete shell and case) doesn't there have to be a certain lenght of time before the breech can be opened to avoid the danger of a flashback?
If so, would this time be shortened if it happened in the middle of a battle?
I know this bit isn't on topic, but is this what happened on the New Jersey?

[Bgile]

You took my #2 and answered it as if it were item#1. Obviously you chose to ignore the point about spotting 5" shell splashes.

Normally a missfire results in repriming the gun and attempting to fire it again. This is what they specifically mention doing when a gun misfired during the last salvo, and it's probably what happened with all the others. Since there is no reference to any of Idaho's guns being out of action at the end, it's likely that none were.

A lot of the ammunition fired by Idaho was not in the normal ready service area of the magazines, and you knew that. Why are you trying to even compare the two situations? They aren't similar at all. The slow rate of fire at the end was due to the people of the exercise desiring Idaho continue to fire after it was taking a long time to get ammunition to the guns. The single gun salvoes were the result.

The modern US battleships had better storage arrangements, consisting of upper and lower shell flats with concentric rings.

We've all made out points here. You are on a crusade to show that the unusually complex loading system used on the quads didn't result in any unusual problems compared with triple or double mountings. I noticed you were very much in the minority on the other site as well. You obviously aren't going to be convinced othewise.

Personally, I feel that the problems were eventually corrected or worked around, and that the quads were reasonably reliable after they had been in service for several years. That doesn't mean the design didn't introduce complexity over and above other nation's weapons, and I remain convinced it was more prone to failure. I believe the complexity was due to British concern over cordite fires, coupled with the desire to mount 4 guns in a turret. US designers were concerned with the complexity of their own four gun turret and were relieved when they didn't have to use it on North Carolina.

Can you find worse performance by individual ships? Probably. There are a lot of them out there to choose from.

With respect to your determination to concentrate on one very long shoot by DoY in heavy seas, I submit that she did indeed do well under those very difficult circumstances. That doesn't mean the quad mounts weren't unusually complex and prone to turret failure in train. It's a separate issue.

[Bgile]

A misfire is a gun out of action, and it will remain out of action until it is safe to clear the breech.
Duncan

That is not necessarily true. You can attempt to fire the gun again. You are implying that Idaho had 13 guns out of action out of an original 6.

[dunmunro]

A misfire is a gun out of action, and it will remain out of action until it is safe to clear the breech.
Duncan

That is not necessarily true. You can attempt to fire the gun again. You are implying that Idaho had 13 guns out of action out of an original 6.

I am saying that over the 3 1/2 hours of the shoot there were 13 intervals of time when one or more guns was out of action.

cheers

Duncan