Shipbucket

Hi Krakatoa,

I'm hoping you could clear something up for me - I'd been under the impression that the Pugliese system was widely regarded as a failure, given the damage the Regia Marina ships took at Taranto, with all three capital ships struck by torpedoes suffering significant hull breaches and requiring grounding to save the ship.

Have I misunderstood the effectiveness of the Pugliese system or is this an AU "this works in my AU" thing?

Regards,
Adam

edit: it should be noted that this damage was off air-launched 18" rather than full-size MTB or submarine torpedoes.

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Quite right Adam, I should have done a bit more reading before making such a claim on the Italians behalf. At the time they were built the Pugliese system was supposed to be good. Future events were to prove otherwise. A phrase I use a lot is "20/20 hindsight", we know what is going to happen but the designers of the ships we draw for the 1900+ do not. Should we not be constrained in a similar fashion.

From Navweaps on Italian Pugliese Torpedo Defense System:

The Italians made the next, much more negative leap in 1934, with the Pugliese System introduced in the Vittorio Veneto Class and the reconstructions of the Conte di Cavour Class and Andrea Doria Class ships. The Pugliese design filled the volume of the TDS with a large cylinder, which was in turn filled with closed tubes reminiscent of those in HMS Ramillies. Pugiese’s theory was that the torpedo would expend its energy crushing the cylinder. In practice the design failed miserably. Following the path of least resistance, the blast traveled around the cylinder and concentrated itself against the weakest point of the complex structure supporting the cylinder: the concave holding bulkhead.

This bulkhead acted much like a dam mistakenly built bowing downstream, rather than upstream against the current. This concave surface was structurally the weakest possible arrangement for containing the force of an explosion, and to make matters worse, the workmanship proved tragically defective. Conte di Cavour sank from a single torpedo hit at Taranto, and Caio Duilio had to be beached to prevent her sinking, also after one hit. Littorio suffered three hits, grounding her bow before she could sink. Vittorio Veneto twice, and Littorio once, suffered severe flooding in dangerous situations at sea when struck by torpedoes, more than such modern ships should have.

Pugliese’s design also consumed tremendous volume, and foreshortened the depth of the armored belt, making the ships so fitted more vulnerable to shell hits below the waterline. Once again, practical experience proved that not every innovation represented an improvement.
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Of course the best way to get around this problem is not to get torpedoed!

Hi K,

Well, to be honest, I think everybody got torpedoes wrong in some sense or another - the lethality of them still wasn't fully understood during WWII, even, look at the damage the IJN were able to do when they landed hits with their Long Lances (which were over-spec for USN TDS, only specified to 320kg warheads vs the Type 93's 500kg warhead). I do wonder if, for instance, an AU RM could make the Pugliese as a cylinder-of-cylinders (for some reason, I keep wanting to type "nested tori", but it's not that, though a similar concept), which would mean that a torpedo detonation would either travel through the Pugliese TDS as intended, or, if trying to go around, still has to expend it's energy crushing the boundary tubes.

Regards,
Adam

edit: whoah, the GIS of "nested tori" is not what I understood that to mean by it, I was thinking more of where a hypercube generalises out to...

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People praise and bash Pugliese without realizing the pro and cons.


Basically, Pugliese did work as it was supposed to when fitted as the integral part of the design, such as in the Littorio class. Now, the definition of "work as it was supposed to" is "survive hits directly on the TDS itself". However, once this condition is ignored, then the problems build up..... but not really the fault of Pugilese itself.

You see, aside from the issues of faulty rebuilt versions (where most of the supposed failure accusations come from), Taranto had the torpedoes explode UNDER the hull. No ship, then and now, can defend against this without some absurd amount of buoyancy and defense system. Taranto was the worst case scenario any capital ship could face, and the fact that RM managed to get away with that little damage compared to the odds itself is a testimony to the well trained crew.

Hi Sumeragi,

It'd thought that the design was fundamentally flawed, the cylinder construction rendering the bulkhead it was attached to too weak to withstand the force of a torpedo explosion, whether it directly impinged on the TDS or not. I'd be interested to find out more, do you have any documentation I could read?

Regards,
Adam

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That was an issue with remodeled ships, not the Littorio class. People try to invalidate the entire system based on what happened to outdated ships.
Let me gather my notes on the matter later, currently working.

The story of the Warrior.

Completed in 1934, the Warrior had just missed the dual purpose revolution by two years. While the older capital ships were being rebuilt to bring them up to date, a modern ship like the Warrior should really have been given priority. To that end the Warrior was taken in hand in 1938 to replace the 6" and 4.7" singles and twins with a dual purpose 4.7" battery. New cross deck catapult, handling facilities and a hangar would provide a better service for the Warriors aircraft which were to be upgraded to the Supermarine Walrus.




The ship returned to service in July of 1939 with Captain Harwood in command. After two months of working up in and around the British Isles, war broke out. With the Graf Spee loose in the South Atlantic, Captain Harwood was promoted Commodore and sent with the Warrior to the South Atlantic to command the South American Division. Ships under command would be The Warrior (8x13.5), Exeter, Cumberland (both 8x7.5"), Manchester, Liverpool (9x6") and 3 H class (6x4") destroyers (all ships from my Fisherless RN). Commodore Harwoods brief was to protect merchant shipping and find and sink the Graf Spee. Harwood used the 6" cruisers and destroyers on the shipping lanes on close support to the major port areas (Rio de Janeiro, River Plate, Sierra Leone, Capetown) escorting multiple ships up to a days journey from the port then dispersing them to return to do it all again and again. This it was felt would force the Graf Spee more than a days sailing from the supported ports and into the wider open areas of the South Atlantic where victims would be harder to come by. The three big cruisers would act together trying to plot where the Graf Spee was heading and get ahead of the GS and using their aircraft to search for the GS. October and November passed without a sighting, just the depressing continued receipt of 'R' for raider reports from merchant ships just before they were sunk. Commodore Harwood was coming under increasing pressure for a result. A stroke of luck befell the group when the Cumberland intercepted a merchant ship on its own which turned out to be the Graf Spee's main stores ship. The Cumberland tried to board the ship but the German crew fired the scuttling charges and down it went taking the intelligence that could have helped to narrow the search for the GS. One piece of good fortune was the reclaiming of crew from some of Graf Spees previous victims.

Into December and Commodore Harwood took the gamble that once the GS knew its supply ship was gone, it would probably take one last chance to have a big result then head for home, by attacking shipping in one of the supported areas. Harwood recalled the Exeter and Cumberland from their sweep down to the Falkands in case the GS had tried for an attack to revenge the happenings of 1914. He ordered the Manchester and Liverpool to rendezvous with him off Rio and all ships would then head for a meeting off the River Plate delta.

Dawn broke on the 13th of December 1939, a day to be unlucky for the Graf Spee. Kapitan Langsdorf and the Graf Spee were headed into the River Plate Delta for one last score before heading north for home. The starboard lookout called out "Ship, bearing north." All eyes and binoculars swivelled to the north. "It looks like a destroyer Herr Kapitan." (Just as well they speak English!) "There is another ship behind it, sir." The first report from the director dispelled all hope, "Lead ship is a 6" cruiser, second ship looks like a battlecruiser with another cruiser following." Kapitan Langsdorf's order was succinct "Full speed!, Steer South-west". His only hope was to make it to neutral waters before the British ships could sink the Graf Spee.

Back aboard the Warrior, Commodore Harwood was all smiles, (he could almost feel the knighthood "arise Sir Henry"). A flurry of signals and orders ensued. The Walrus was launched and was to provide invaluable assistance in the coming hours. The Warrior was ordered into the lead with the two 6" cruisers astern, full speed was ordered and the signal 'Chase" was raised to the masthead. The Exeter and Cumberland reported in that they were 60 miles south of the Commodores position and should be in a position to intercept the Graf Spee in 30-40 minutes at the current closing speed. The jaws of the trap were about to spring. The Graf Spee was 20 miles in the lead and it would take some time for the British ships to catch up and be within effective firing range. Ten minutes later the Graf Spee opened fire with its after turrets three guns. While no hits were scored it was an uncomfortable feeling to know your enemy outranged you.

Aboard the Graf Spee, Kapitan Langsdorf thought his chances were about 50/50 to reach neutral waters when the forward lookout reduced his chances to zero. "Cruisers in sight to the south!" The main gun battle was about to begin. Kapitan Langsdorf knew his best chance was to engage the cruisers to the south and hope to blast a way through them. He ordered a change of course enough to allow his after turret to bear on the two cruisers and kept on.

The Cumberland and Exeter also turned to bring all turrets to bear, the 7.5" guns opening fire at 30,000 yards and closing. While the 7.5" shells may not have been able to penetrate the Graf Spees armour at that range they could damage and destroy all the minor weaponry and systems. An early hit burnt out the aircraft that was being readied for launching causing a petrol fire amidships. Several of the 5.9" and 4.1" were put out of action from subsequent hits. The reason the two cruisers were able to hit the Graf Spee at the longer ranges? The Walrus launched by the Warrior was spotting for them. 30 minutes later the first shells from the Warrior arrived signalling the end. An hour later the Graf Spee was a burning wreck, all its guns out of action, but its flag still flying. Manchester was ordered to sink the hulk with torpedoes. Three torpedo hits caused more internal explosions and the mighty Graf Spee rolled over and sank. Only 144 of its crew were pulled from the water, Kapitan Langsdorf was not among the survivors.

Epilogue:
To cries of "The Navies here!!" sailors from Captain Vians Tribal class destroyer storm aboard the Altmark in a Norwegian fjord rescuing hundreds of survivors from Graf Spees victims. The Altmark had run out of supplies for the Graf Spee and had been ordered home by Kapitan Langsdorf with all the prisoners aboard. The ship sunk in the South Atlantic was the Graf Spee's second supply ship.

Oh, now that refit is pretty. Can't help but think though that twelve 4.7s would suffice leaving room atop that platform amidships for better boat handling or more small-calibre AA.

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Thanks for your comments B.B.

I did actually remove some larger ships boats to make room for that fourth superfiring 4.7". I figured once its raider hunting days were over it would go to the fast carrier escort role where the extra heavy AA would be useful. I have one refit to go for that ship, a 1943 version where the hangar and aircraft go overboard and extra AA and the bigger boats make their reappearance.

Spiffy. I look forward to seeing it.

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AU Projects: | Banbha et al. | New England: The Divided States
Blood and Fire