# USS San Fransisco v Deutschland v Zara v Takao v Norfolk?



## Lucky13 (Jun 30, 2009)

Which was overall the best design?


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## delcyros (Jun 30, 2009)

All had their share of merits. Deutschland had the most powerful armement and firecontroll and certainly the best endurance and range but otherwise was the worst of the ships under discussion (underprotected with unreliable engines, slow design). Zara and Norfolk are good performer but the french Algerie certainly is better. San Francisco is an excellent design with very powerful firecontroll, good armement and excellent (for a cruiser) armour but misses an effective torpedo suite. 
I would vote for Takao. They had powerful armement, good protection, high margins of speed, seakeeping and range. They also had the best torpedo suite of any of the cruisers under discussion. Their drawback is a lack of metacentric stability.


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## Glider (Jun 30, 2009)

Personally I like the Algerie, its a good balance without any obvious problems apart from items such as radar which it didn't have access to.

A second choice would be the Prinz Eugen, I know there are some questions over her engines but the crew seemed to get the measure of them. She was also tough.


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## DonL (Jul 1, 2009)

@ Glider

the Prinz Eugen is a very poor design for 18600ts. Not enough protection (less than Algerie, Zara, New Orleans and Deutschland Class) and the range was very poor too. Only the guns and the Speed are ok.

Algerie is the most balanced Class for a Heavy Cruiser.

The choose from Lucky i will go for the Deutschland Class, because of the firepower, good protection and the best range.


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## timshatz (Jul 1, 2009)

Go with Delc on this one, simply due to all those 8" shells coming your way. Big problem for being on the receiving end. Couple the speed and torpedoes (Long Lance?) and you get a very, very dangerous ship.


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## Lucky13 (Jul 1, 2009)

How does the guns and ammo compare between these ships?


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## renrich (Jul 1, 2009)

I go with San Francisco, barely, because she was better protected, her fire control was better, she had much better triple A. Without the Japanese torpedos, it would not be close.


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## syscom3 (Jul 1, 2009)

renrich said:


> I go with San Francisco, barely, because she was better protected, her fire control was better, she had much better triple A. Without the Japanese torpedos, it would not be close.



In the end, it is AAA effectiveness that decides who is best.


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## Juha (Jul 2, 2009)

I'd say Algerie, and IIRC it was a real Treaty Cruiser. Zara, Takao and Hipper were in reality bigger, in real life dictatorships often cheated.

BTW the main asset of CAs was their 8" guns, if AAA would have been the most important thing all navies would have removed the 8" turrets from their CAs and put as much as possible AAA in place. Only class which could have used their 8" guns for reasonable AA work was RN Counties, which had 70deg elevation for their main armament and fairly high RoF. On the other hand RN HACS was a substandard HA director.

Juha


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## fastmongrel (Jul 3, 2009)

Juha said:


> On the other hand RN HACS was a substandard HA director.
> 
> Juha



A lot of research has been done on WWII naval AAA control and the conclusion seems to be that the RN HACS wasnt quite as bad as has been made out and the US Mk33/37 wasnt quite as good as has been made out. All WWII predictors suffered from the same problem working out a firing solution on land is hard enough but on a ship that rolls pitches turns and vibrates is a whole different ball game. A quote I remember (sorry cant find the quote but I will have a good look later) said that trying to hit another ship was like trying to shoot from a trotting horse but trying to hit a manouvering attacking aircraft from a ship was like trying to shoot from a galloping horse. 

This is an interesting thread about the HACS and other predictors

All the World's Battlecruisers/ The World's Last Pre-Dreadnoughts :: View topic - RN HACS worse than all others?

All WWII predictors seemed to do reasonably well against level flying bombers but simply couldnt generate solutions fast enough against diving attacks a problem that wasnt solved till the development of electronic computers.


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## Juha (Jul 3, 2009)

Hello Fastmongrel
thanks for the link, I had time to read only some of the tread. My negative oppinion on HACS is from British books, for ex from Brown's British BB book from Nelson to Vanguard. And some old discussions on Japanese Aircraft site seemed to confirm that, but the writers were at least mostly from States. Also what happened in Med 41-42 seemed to confirm that RN heavy AA wasn't as good as was expected. Also IIRC PoW and Repulse got only 3 Jap a/c when they were sunk and IIRC 2 of those 3 were allocated to the pom-pom on Repulse's B turret. MHO not very good result for 2 capital ships and 3 DDs.

Juha


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## fastmongrel (Jul 4, 2009)

Hi Juha
Your right that the RN navy AAA record wasnt good but in comparison to everyone elses at the same time it was reasonable, the point being that was about as good as it got at the time. 

The German navy had the type 1937 High Angle control on its larger units theoretically it was a superb system with multiple gyros and gimbal rings giving Tri-axial stabilization and a possible continuous automatic firing solution. Unfortunately it weighed 40 tons was overcomplex suffered from vibration and if one of the gyros tumbled due to heavy weather or a hit on the ship or even a near miss it could take 20 minutes for the gyros to be brought back up to speed. 

The USN Mk33 which was the most common predictor at the start of the Pacific war was a good system against high level bombing if the target was doing less than 275 knots but it needed modifications to make it work against dive bombers and even then it only worked if the aircraft held a steady course it couldnt give a firing solution for a manouvering dive bomber. The Mk37 was almost certainly the best system in WWII when used in conjunction with the best Dual Purpose gun in WWII the 5 inch 38 calibre but it suffered problems with its gyros and servos and needed the addition of a slewing sight so that the Director officer could get on a target quickly and hold it till the Director computer created a firing solution. It took a lot of work to make it the good system it was. However it was not particulary effective against Kamikaze attacks and the usual practice was to use the slewing sight and VT proximity fuses and basically hose shells at the target the Director officers Mk1 biological computer and eyeball worked faster than any predictor.

The Japanese Type 94 predictor was similar to the German system in that it was overcomplex and fragile. From reports it seemed to suffer a problem in that a small aiming error at the start of an attack could very quickly become a major error.

The RN HACS system was generally the lightest of the major navies systems but it relied a lot more on the skill of its operators and Director officer than other navies systems. This was the reason the Admiralty liked the MK 37 so much it was more user friendly for raw conscripts. It is noticeable from ships combat reports how the AAA got better the more actions there were as the predictor crew became more experienced. Of course thats not good if your sunk the first time your in action. The last wartime RN system the MkIV director was probably the secound best AAA director of the war after the USN Mk37 but an awful lot of metal and explosive was fired for each aircraft brought down. 

The Repulse and the PoW were up against what was the best anti shipping airforce in the world at the time I very much doubt that any contemporary ships would have lasted much better especially when you consider that the Admiral was a blockhead and shouldnt have been anywhere near that area without proper fighter cover. As for the Med in 41/42 its a wonder that any RN ships survived. The evacuation of Crete ( known as the death ride of the navy) resulted in heavy losses. Two cruisers HMS Gloucester and HMS Fiji were only sunk when they ran out of ammunition. The Captain of Fiji said the sky was nearly black with aircraft over Gloucester as the Luftwaffe went in for the kill on the defenceless ship.


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## Juha (Jul 4, 2009)

Hello Fastmongrel
I tended to agree with you.
A couple IIRC comments. IIRC the system in Scharnhorst and in Gneisenau was more vulnerable to gyro toppling than that of put into Bismarck and Tirpitz. Bismarck's AA suffered from the fact that its 2 rearmost AA directors were old design because according to Germany-Soviet Union treaty Soviets were allowed to get their blue-prints and to visit them amd KM didn't want to reveal its newest tecnology to Soviets.
I agree that PoW and REpulse were put into rather hopeless situation because of the commanding admiral's decisions. But still PoW did badly even against the level bombers.
On attack on Illustrious Valiant had probably the best AA suite the RN had at the time, 4.5" being IMHO better AA gun than the 5.25". Still its AA fire was rather ineffective, IIRC South Dakota did better at Santa Cruz when protecting the Enterprise with CL(AA) San Juan. That's more significant because pre-war/early war RN doctrine put much more emphasis on AA protection of main fleet, USN counted more on its fighters. That was shown in the size of air wings and in size of AA in modern CVs (Ark Royal and Illustrious class vs Yorktowns)
But as I wrote this was IIRC and I'm glad to learn more on the subject.

Juha


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## fastmongrel (Jul 4, 2009)

Juha totally agree with you about Fighter defence versus gunnery defence. If only I could get my hands on a time machine I would go back to before the war change the Illustrious design to a modified Ark Royal 10% larger in all dimensions including the lifts. Order as many Grumman Wildcats as grumman could build and get them working on the Hellcat earlier.


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## syscom3 (Jul 4, 2009)

It seemed the US cruisers could carry quite a few 40mm (dual and quad mounts) and more than a few 20mm (which were essentially useless).

In fact, the light AA (20 mm) didnt really serve any purpose at all. The effective range for them meant they were "revenge" weapons for after a bomb or torpedo was dropped/launched.


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## fastmongrel (Jul 4, 2009)

Juha Good call, you are right about the earlier German predictor type1933 having the big gyros that toppled easily. The type 1937 had smaller less topple prone gyros it was fitted in the Prinz Eugen and Tirpitz cant find out if they were fitted to Bismark but if you have read that it was fitted with less advanced predictors aft. Then that would seem to mean it had 37s forrard and 33s aft.


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## Glider (Jul 4, 2009)

Juha said:


> Hello Fastmongrel
> thanks for the link, I had time to read only some of the tread. My negative oppinion on HACS is from British books, for ex from Brown's British BB book from Nelson to Vanguard. And some old discussions on Japanese Aircraft site seemed to confirm that, but the writers were at least mostly from States. Also what happened in Med 41-42 seemed to confirm that RN heavy AA wasn't as good as was expected. Also IIRC PoW and Repulse got only 3 Jap a/c when they were sunk and IIRC 2 of those 3 were allocated to the pom-pom on Repulse's B turret. MHO not very good result for 2 capital ships and 3 DDs.
> 
> Juha



Re the POW against the Japanese high level bombers you are correct about the number of planes shot down but I am pretty confident that a good number of the high level bombers were damaged to the degree that they didn't make a second attack which was the original plan.

I will need to dig around to find the statement to support his but for now I would you to put a question mark down on the effectiveness or otherwise against level bombers.


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## Freebird (Jul 5, 2009)

fastmongrel said:


> Hi Juha
> 
> The Repulse and the PoW were up against what was the best anti shipping airforce in the world at the time I very much doubt that any contemporary ships would have lasted much better especially when you consider that the Admiral was a blockhead and shouldnt have been anywhere near that area without proper fighter cover. As for the Med in 41/42 its a wonder that any RN ships survived. The evacuation of Crete ( known as the death ride of the navy) resulted in heavy losses. Two cruisers HMS Gloucester and HMS Fiji were only sunk when they ran out of ammunition. The Captain of Fiji said the sky was nearly black with aircraft over Gloucester as the Luftwaffe went in for the kill on the defenceless ship.




The PoW also lost power early during the attack, and the ship had not been properly worked up.


The blame does not go to the Admiral who was ORDERED to do what he did, but goes to the Minister of Defence who cooked up the damn-fool operation, and waited to give the order to withdraw these valuable assets until the morning of the 10th {in the UK} at which point they were already sunk.



But back on track, - Of the CA's does anyone recall the effectiveness of the County's AAA? The Cornwall Dorsetshire didn't do very well either against the bombers.


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## Juha (Jul 5, 2009)

Hello Glider
you are right IIRC corectly 5 high level bombers were damaged of which 2 turned immediately to home. But the bombers made one hit on Repulse and IIRC also one on PoW.

Hello Freebird
Phillips could have asked a sqn of fighters, they were available, for protection but never called them, after PoW was hit Tennant, CO of Repulse, send the message for fighters but they arrived too late. If Phillips had been clever he would have call help at least when the level bombers were noticed if the snoopers around didn't bother him. Brewsters would have had some effects on Bettys and Nells.

On Counties, IMHO no cruisers at the time without fighter cover would have had much chance against mass attack of IJN Vals.

Juha


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## delcyros (Jul 5, 2009)

The problem with the US 20mm and 40mm BOFORS was the shell. It contained to little high explosive to guarantee a kill (only 65gramms in case of the 40mm). In comparison to this even the poor 37mm FLAK AAT rounds used on german ships were as deadly as a US 3"/50 AAA round (both at ca. 250 to 350 gramms of high explosive depending on fuze mechanism).
The pom poms used on british ships had to low a muzzle velocity but a high rate of fire. This was adaequate when designed but soon became obsolete as performance of attacking A/C rapidly improved. The high density of fire was the greatest asset of this weapon in close AA defense.


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## magnocain (Jul 6, 2009)

As far as Heavy Cruisers go, the Alaska would come out on top.


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## Freebird (Jul 6, 2009)

Juha said:


> Hello Glider
> you are right IIRC corectly 5 high level bombers were damaged of which 2 turned immediately to home. But the bombers made one hit on Repulse and IIRC also one on PoW.
> 
> Hello Freebird
> ...



There was alot of stupidity in that regard due to the RN policy of radio silence. Phillips couldn't call the RAF after the first attack because the radio was knocked out. Tennant wasn't told right away that no call had gone out, only when it was too late did he realize. And the Brewsters wouldn't have "some effect", they would have completely prevented the destruction IMO. The "Repulse" dodged 3 torpedo runs, it was only by launching from 3 directions simultaneously that the Japanese got a hit. {Tennant's crew had much more training than the PoW, they were very skilled at "combing". Even a dozen Buffaloes would be enough to prevent the bombers from making a coordinated attack.


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## syscom3 (Jul 6, 2009)

magnocain said:


> As far as Heavy Cruisers go, the Alaska would come out on top.



Thats classified as a battle cruiser.


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## Freebird (Jul 6, 2009)

syscom3 said:


> Thats classified as a battle cruiser.



Yes, and also it looks like the comparison is circa 1941, not 1944


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## parsifal (Jul 6, 2009)

Actually the Alaskas are described in Conways as "Heavy Cruisers free from all treaty restrictions"

They make an intersting comparison to the japanese B-65s and the German "P" Classes, possibly also the Soviet Kronstadt Class

But not relevant to this discussion.

For my money its the Takaos. These were very tough and capable ships in my opinion. The French Algerie gets an honourable mention....


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## DonL (Jul 6, 2009)

> Actually the Alaskas are described in Conways as "Heavy Cruisers free from all treaty restrictions"



Thats a very funny description for a battle cruiser or little battleship with 34250ts.



> They make an intersting comparison to the japanese B-65s and the German "P" Classes, possibly also the Soviet Kronstadt Class



No, the real comparison is the Dunkerque class with 36360ts.
And there is nothing to win for the Alaska accept speed and perhaps AAA.

Sorry for the off topic


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## Juha (Jul 6, 2009)

Hello Freebird
the first attack was by level bombers, the disabilating torpedo attack happened after it. IMHO at least when they got the visual sighting of level bombers it was time to Phillips to ask fighter support. Less indoctranated officer would have asked air cover, 4 fighters in time, after the snoopers were seen.

I was not blaming Tennant at all, he did very good job.

"some effect" was an understatement. And we don't know how it would have gone if Brewsters would have arrived in time, I'm pretty sure that they could have prevented at least some torpedo hits.

Juha


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## Freebird (Jul 6, 2009)

Juha said:


> Hello Freebird
> the first attack was by level bombers, the disabilating torpedo attack happened after it. IMHO at least when they got the visual sighting of level bombers it was time to Phillips to ask fighter support. Less indoctranated officer would have asked air cover, 4 fighters in time, after the snoopers were seen.
> 
> I was not blaming Tennant at all, he did very good job.
> ...



Yes correct, I have a book with the timeline, IIRC the first torpedo hit was about 60 min after the first sighting, the fighters could have been there fast enough to save Repulse certainly, and maybe PoW too. The ships were hit by bombs first, which had no serious effect, then the torpedos afterwards. 

My point was that the the Counties were lass well AAA protected,IMO, but even the better protected ships would be vulnerable to an attack like the one on "Cornwall"


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## delcyros (Jul 6, 2009)

Unfortunately for the ALASKA´s, they were classified as large cruisers by the USN. This terminology was used back in ww1 for the german battlecruisers: They were officially termed "Große Kreuzer", which literally translates into "large cruiser". This classification becomes the battlecruiser, so the USN unintendedly used an older classification, perhaps unaware that this very one was already used for battlecruisers before.
Whatever they called them, they were bc´s.


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## timshatz (Jul 6, 2009)

Think the Takao's torpedoes are not getting enough credit. It was a mistake for the US that they did not put torpedoes on their HC. One they paid for in the Solomons. If you consider Salvo Island and other actions (Salvo being the one that is a definite that Cruiser torpedoes did the job), you have a weapon system that was far more effective because of their inclusion in the ship's design. 

The Japanese Long Lance was a ship killer.


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## syscom3 (Jul 6, 2009)

timshatz said:


> .....If you consider Salvo Island and other actions (Salvo being the one that is a definite that Cruiser torpedoes did the job), ....



Its "Savo Island", not "salvo".

LOL .... although you could say that since so many salvo's were fired near by during the campaign, it should get that name.

(sorry I am being te spelling police)


But when you consider the torpedo's and their systems took up space that would have been put to better use with AAA, I think the IJN lost more in the long run.


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## timshatz (Jul 6, 2009)

Whoops, my bad. That's what you get for not proof reading!

Considering your POV, it's a fair point. In the early part of the war, up to about 1943, before US Airpower got it's act together, the torpedoes on Japanese Cruisers paid for themselves. Thereafter, not so. Replacing them with AAA would've been a good idea. 

By the time you get around to Leyte Gulf, the Long Lance was over as a weapon's system that made a difference. 

However, one point about AAA vs Torps, the AAA is a defensive weapon and the Torp is an offensive weapon. With the AAA, it's a matter of time (as the kamikazes showed) before you get hit. Even the best of them gets it sooner or later.


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## fastmongrel (Jul 6, 2009)

delcyros said:


> The problem with the US 20mm and 40mm BOFORS was the shell. It contained to little high explosive to guarantee a kill (only 65gramms in case of the 40mm). In comparison to this even the poor 37mm FLAK AAT rounds used on german ships were as deadly as a US 3"/50 AAA round (both at ca. 250 to 350 gramms of high explosive depending on fuze mechanism).



Hi Delycros the figure of 250 to 350 gramms of explosive for a 37mm shell sounds like and awful lot for a shell weighing approximately 640 grams was this for a Minengeschosse (not sure of correct spelling) shell similar to the shells fired by the 30mm aircraft guns used by the Luftwaffe


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## syscom3 (Jul 6, 2009)

timshatz said:


> Whoops, my bad. That's what you get for not proof reading!
> 
> Considering your POV, it's a fair point. In the early part of the war, up to about 1943, before US Airpower got it's act together, the torpedoes on Japanese Cruisers paid for themselves. Thereafter, not so. Replacing them with AAA would've been a good idea.
> 
> ...



I would consider the increasing effectiveness of the allied radar as starting to neutralize the torpedo effectiveness.

But the USN were slow learners regarding the IJN torpedo effectiveness (and night fighting doctrine) thus the Japanese get credit for their cruiser capabilities.


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## delcyros (Jul 6, 2009)

high explosive content of AAA-rounds:

*Germany:*
3.7cm FLAK C/30: 365 Gramm, including tracer (HE-T auto-destructive impact AAA ammo)
8.8cm FLAK C/31 33: 900 Gramm, (HE-T auto destructive impact AAA ammo, the segmentary HE-T had about 840 Gramms, the very effective late war HEI-T about 1000 Gramm)
10.5cm FLAK C/33: 3250 Gramm (HE-T auto-desturctive impact AAA ammo)

*USN:*
20mm Oerlikon/70: 8 Gramm (HE-T auto destructive impact AAA ammo)
40mm BOFORS:/56:68 Gramm (HE-mark2 impact fuse)
3"/50RF: 340 Gramm (HC-impact fuse or 240 Gramm for AA-VT proximity fuze)
5"/38: 3300 Gramm (AA-VT proximity fuze)

*RN:*
40mm/39 (2pdr): 71 Gramm (HE impact fuse)
4"/45: unknown
4.5"/45: unknown
5.25"/50: 2950 Gramm (HE impact fuze. An VT prosimity fuze was introduced in 1944)
*
IJN:*
25mm/60: 10 Gramm (common impact fuze)
80mm/60: 310 Gramm (common HE impact fuze)
100mm/65: 950 Gramm (HE impact fuze)
127mm/50: 4000 Gramm (ASW auto destructive fuze)


The shift to thin walled but high capacity rounds gave the KM AAA some good damage infliction potential.


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## timshatz (Jul 6, 2009)

syscom3 said:


> I would consider the increasing effectiveness of the allied radar as starting to neutralize the torpedo effectiveness.
> 
> But the USN were slow learners regarding the IJN torpedo effectiveness (and night fighting doctrine) thus the Japanese get credit for their cruiser capabilities.



Good point. After the US got it together with it's use of Radar, the advantage of the long lance was largely muted. By 1943, they had learned to lay back behind smoke screens and fire from a distance of 15,000 yards, utilizing the gun/radar combo to produce results. 

Good point.


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## fastmongrel (Jul 6, 2009)

> The shift to thin walled but high capacity rounds gave the KM AAA some good damage infliction potential.



365 gm of explosive in a 640gm shell must mean the shell had wafer thin walls. Even the 88 c31/33 with 1000 gm of explosive that is only about 10% of shell weight. I dont know much about shells but I imagine the shell would have been fused to explode on impact would Semi Armour piercing rounds with a lower explosive content have been fired at the same time.


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## delcyros (Jul 6, 2009)

AAA shells are not armour piercing or semi armour piercing. The decision whether to use mine type of rounds or thicker side walls depends on the task profile. A mine round will be very deadly under any direct hit condition owing to superior blast effects but may have almost no effect if time based auto-destruction appears without physically hitting the enemy aircraft. It relies entirely on blast effects. A thicker walled (well, a normal walled to be true) AAA projectile does produce more and heavier splinters which do retain their energy better and allow for a more extended damage zone by splinter damage IN ADDITION to blast damage of close by hits.
The 37mm to 57mm size is still to small to be used as an efficient splinter AAA-round and needed direct hits, so making the shell a blast relying mine round with high capacity was a clever thing to do. The larger 88mm projectile was large enough in order to make for a regular AAA-shell. Blast and splinter damage was caused by these hits. Large bombers had quite some surviving probability when splinter damage was inflicted by the 88mm but likely no or a very reduced survivability when blast damage occurred (a direct 8,8cm hit is a really nasty event to deal with).
The 40mm and 20mm projectiles on other navies light AA tried to be a normal Flak round with low high explosive content but they were to small for effective splinter display and had to low an explosive capacity to ensure a kill under direct hit conditions. That´s pretty close to the worst of both worlds. Don´t take me wrong, it´s not the 40mm BOFORS, the gun is excellent, it´s the ammunition which was defective by design and didn´t maxed out the potentioal of the gun.


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## Glider (Jul 7, 2009)

The German Navy also used the 40mm Bofors as a replacement for the 37mm towards the end of the war, can I ask if you know what kind of shell they used, the 'standard' 40mm or a 37mm type design with extra explosive.


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## delcyros (Jul 7, 2009)

There were many projectile types in service for the 40mm BOFORS. It appears that this gun was first introduced by the Wehrmacht in the early 30´s provided with normal AAA-rounds. When it appeared on warships from 1943 again, the 40mm was provided with a mine round type shell, containing almost 400 Gramm of high explosive. The cruiser PRINZ EUGEN had very good experience with a mixed 37mm / 40mm FLAK and radar assisted predictors in 1945 against numerous soviet low level bomber attacks.


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## parsifal (Jul 7, 2009)

I have no idea on the relative effecctiveness of the different shells....I wonder how much more efficient Germans ammunition in comparison to Allied ammunition was in bringing down aircraft. By "efficient" I mean how many rounds per kill were needed of the Mine shells to bring down an aircraft as compared to the allied 40mm rounds.

On land, the average number of rounds expended per kill by the Flak artillierie in 1942 was about 3500 to 4000 for each kill of a high level strategic bomber. By comparison, I recall reading a USN report somewhere that talked about 1500 rounds against low flying Japanese aircraft. This figure had apparently dropped to about 500 RPK by late '44. But the German and allied RPKs are simply not comparable....the data would need to be against like targets with like weapons. Still if there is any information out there, it would be useful to know.


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## timshatz (Jul 7, 2009)

parsifal said:


> I have no idea on the relative effecctiveness of the different shells....I wonder how much more efficient Germans ammunition in comparison to Allied ammunition was in bringing down aircraft. By "efficient" I mean how many rounds per kill were needed of the Mine shells to bring down an aircraft as compared to the allied 40mm rounds.
> 
> On land, the average number of rounds expended per kill by the Flak artillierie in 1942 was about 3500 to 4000 for each kill of a high level strategic bomber. By comparison, I recall reading a USN report somewhere that talked about 1500 rounds against low flying Japanese aircraft. This figure had apparently dropped to about 500 RPK by late '44. But the German and allied RPKs are simply not comparable....the data would need to be against like targets with like weapons. Still if there is any information out there, it would be useful to know.



Might also have something to do with ships having compacted AAA and firing at a target with a 0 (or close to 0) defection while a land battery of AAA would normally be shooting deflection shots anywhere up to 90 degrees. Of course this only applies to a single ship. In a formation, it would be different for the other ships not being attacked. 

Also, aircraft were closing on the ships while the land batteries were rarely the target and usually got a 90 (or some variation of) deflection shot at distances up to 30K feet. Makes land shooting more problematic.

Lastly, Germany did not have the Prox fuse whereas the US Navy had it for anything over 40mm. 

Just some food for thought. Additional info.


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## renrich (Jul 7, 2009)

The Alaska class may have been called large cruisers but, in reality, they were BCs, built in reply to Scharnhorst class. They were useful only because of high speed and heavy AA armament. The US's first treaty cruisers, Pensacola class, were designed and built with torpedo tubes, which were later removed. I believe the theory on that was that the 8 inch guns and high speed of the cruisers negated any capability of torpedoes. Later in the war with the efficient use of radar controlled gunfire, that may have been true. Originally, the Pensacolas were not called heavy cruisers but were labeled as scout cruisers. As far as triple A on US cruisers is concerned, the prewar ships rapidly gained more and more AAA capability along with the equipment and personnel to operate them which made them top heavy and overcrowded. One of my uncles was a CGM(chief gunner's mate) on Salt Lake City(CA25) from 1941-43. In 1943, (I think) they were in Pearl Harbor for an overhaul. The ship carried 4 scout planes and they prevailed upon the shipyard to install two twin mount 40 mms amidships, just aft of the catapults and offloaded two of the scout planes. All of this without official permission from Buships.


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