2, 3 and 4 gun turrets on battleships...
Discussion
OutInTheShed said:
Can aim in 4 different directions?
Battleships can generally aim at as many different targets as they have gunnery director towers; RN KGV class had two main gunnery directors and 4 secondary gunnery directors. Bismarck had 3 main directors. and 4 secondary directors. The turrets generally have their own range and direction gear but it's usually less accurate through using cheaper or less sophisticated optics, no gunnery computers and for later vessels not being coupled to radar, so it would be like herding cats getting them to aim at 4 different targets and not much hope of hitting them.DodgyGeezer said:
something just struck me the other day (I'd read an article on Bismark): what was the advantage (if any) for the Bismark to have 4 * 2 gun turrets vs the 3 * 3 guns or even 3 * 4 gun turrets of her contemporaries?
Being only two guns per turret, and with a greater distance between the guns in the Bismark/Tirpitz turrets meant that there was less interference between the guns, which significantly increased accuracy when both fired together. I've seen a long time ago, that the accuracy tests done by Tirpitz showed accuracy of 120-125m circle at 20-25km range.Quad gun turrets were the least accurate it seems by some way.
The Americans chose triple turrets for the Iowa Class accepting the trade off in terms of accuracy.
aeropilot said:
Being only two guns per turret, and with a greater distance between the guns in the Bismark/Tirpitz turrets meant that there was less interference between the guns, which significantly increased accuracy when both fired together. I've seen a long time ago, that the accuracy tests done by Tirpitz showed accuracy of 120-125m circle at 20-25km range.
Quad gun turrets were the least accurate it seems by some way.
The Americans chose triple turrets for the Iowa Class accepting the trade off in terms of accuracy.
I understood that that B/T's accuracy was way more because the Germans had a great understanding of all aspects of the gunnery problem (which includes everything from ammunition temperatures, machine tolerances, target information, alignment, meteorological data) and a large stable platform to shoot from. The turret configuration being just a small part of that.Quad gun turrets were the least accurate it seems by some way.
The Americans chose triple turrets for the Iowa Class accepting the trade off in terms of accuracy.
Interference can be overcome by sequenced firing so adjacent guns are triggered after small delays. It's only really a thing for broadsides, once on target often guns can fire at will and it becomes a race between loading crews. Given the weight/packaging advantages of triple and quad turrets it's a small price to pay.
Evanivitch said:
aeropilot said:
Being only two guns per turret, and with a greater distance between the guns in the Bismark/Tirpitz turrets meant that there was less interference between the guns, which significantly increased accuracy when both fired together. I've seen a long time ago, that the accuracy tests done by Tirpitz showed accuracy of 120-125m circle at 20-25km range.
Quad gun turrets were the least accurate it seems by some way.
The Americans chose triple turrets for the Iowa Class accepting the trade off in terms of accuracy.
I understood that that B/T's accuracy was way more because the Germans had a great understanding of all aspects of the gunnery problem (which includes everything from ammunition temperatures, machine tolerances, target information, alignment, meteorological data) and a large stable platform to shoot from. The turret configuration being just a small part of that.Quad gun turrets were the least accurate it seems by some way.
The Americans chose triple turrets for the Iowa Class accepting the trade off in terms of accuracy.
There wasn't much in it, everyone with battleships had mastered optical fire control by the 1930s, the main capital ship differences were the germans not being very experienced at battleship design, the italians having poor ballistics/ammunition/propellant and the japanese never really exploiting radar despite having it, even then these mattered less than the decisions made at the tactical level, availability of units to be where they needed to be and happenstance like weather, intelligence, spotting etc.
hidetheelephants said:
Any turret knocked out loses a smaller percentage of main battery firepower; the cost is greater ship size is needed for a given level of armour protection and speed. Drachinifel on Youtube has videos that go into the minutiae.
Yep - luckily I spotted this otherwise I would have repeated the same 
https://www.youtube.com/@Drachinifel
DodgyGeezer said:
something just struck me the other day (I'd read an article on Bismark): what was the advantage (if any) for the Bismark to have 4 * 2 gun turrets vs the 3 * 3 guns or even 3 * 4 gun turrets of her contemporaries?
Ironically this is his latest video (not his channel though) from 4 hours ago Bismarck WAS NOT a Super Shiphttps://youtu.be/8Hrr7XXZIZU?si=dqfVP445PRATb4TN
hidetheelephants said:
There wasn't much in it, everyone with battleships had mastered optical fire control by the 1930s, the main capital ship differences were the germans not being very experienced at battleship design...
Tell that to the Hood. I thought the German pocket battleships were very good, and their gunnery superior to ours, but they were badly used.Treaty limitations drove a lot of the choices. Britain/France generally complied with the treaty restrictions, Germany/Japan did not.
Nelson/Rodney were 3*3 in a group as it was the only way to get 9*16 guns with the desired armour and speed within the permitted weight.
KGV class likewise driven to quads for the same reason, and the admiralty not wanting any more three gun turrets.
For an unusual approach look at the last French ships, two classes each with two four gun turrets, only one magazine area to armour.
In reality once they started getting hit the layout didn’t matter much, things stop working when you hit them with one ton plus shells travelling at high speed as the descriptions of Bismark’s final hours shows. I don’t think either Rodney (?) or KGV were hit by 15” shells
Nelson/Rodney were 3*3 in a group as it was the only way to get 9*16 guns with the desired armour and speed within the permitted weight.
KGV class likewise driven to quads for the same reason, and the admiralty not wanting any more three gun turrets.
For an unusual approach look at the last French ships, two classes each with two four gun turrets, only one magazine area to armour.
In reality once they started getting hit the layout didn’t matter much, things stop working when you hit them with one ton plus shells travelling at high speed as the descriptions of Bismark’s final hours shows. I don’t think either Rodney (?) or KGV were hit by 15” shells
IJWS15 said:
KGV class likewise driven to quads for the same reason, and the admiralty not wanting any more three gun turrets.
Not quite, as the Lion-Class Battleships which were to follow the KG-V Class, were going to have triple 16 inch turrets, but they were a new and complicated design which were slowing the build, and they ended up cancelling them as it was going to be quicker to build a single new ship using existing tried and tested 15 inch guns in 4 x gun turrets, which became Vanguard.Simpo Two said:
Tell that to the Hood. I thought the German pocket battleships were very good, and their gunnery superior to ours, but they were badly used.
POW managed to hit Bismarck pretty quickly despite an inexperienced crew and a load of dockyard mateys still adjusting/breaking things until they worked; the damage while superficial influenced decision-making onboard Bismarck which brought her closer to other RN capital ships. Hood would have been modernised had A Hitler not inconveniently invaded Poland and the armour layout was on the to-do list, long range plunging fire is hypothesised to have hit a target area a few feet across at a moment Hood was rolling away from the german ships exposing the hull below the armour belt in heavy seas; that's remarkable luck as well as good gun laying, similar weaknesses existed in Bismarck's armour layout.Graf Spee was disabled by 3 light cruisers, there's not much good about that.
KGV was meant to be 3x3 15”, but the British were desperate for every one to stick to treaty limits on gun size, so deliberately down-gunned to 3x4 x 14”. That was too heavy for the treaty, so rather than cheat moved to 2x4 x 14” and 1x2
Bismarck- remember the Germans had missed out on 20 years of R&D and warship building. So they were unable/ uncomfortable with building 3 x 15” turrets and minimising the interference between the guns - they were behind the Allies and the Italians/ Japanese in experience. Bismarck was behind her contemporaries in things like the hull form as well.
For Scharnhorst - yes, 3 x 11”, but had a plan to rebuild to same turrets as Bismarck.
Bismarck- remember the Germans had missed out on 20 years of R&D and warship building. So they were unable/ uncomfortable with building 3 x 15” turrets and minimising the interference between the guns - they were behind the Allies and the Italians/ Japanese in experience. Bismarck was behind her contemporaries in things like the hull form as well.
For Scharnhorst - yes, 3 x 11”, but had a plan to rebuild to same turrets as Bismarck.
hidetheelephants said:
long range plunging fire is hypothesised to have hit a target area a few feet across at a moment Hood was rolling away from the german ships exposing the hull below the armour belt in heavy seas
There is always some luck involved, but I thought the fatal shot went through the deck.Simpo Two said:
hidetheelephants said:
long range plunging fire is hypothesised to have hit a target area a few feet across at a moment Hood was rolling away from the german ships exposing the hull below the armour belt in heavy seas
There is always some luck involved, but I thought the fatal shot went through the deck.Forum | Boats, Planes & Trains | Top of Page | What's New | My Stuff