Littorio class design flaws?

From the Washington Naval Treaty to the end of the Second World War.
User avatar
Dave Saxton
Supporter
Posts: 3093
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Littorio class design flaws?

Post by Dave Saxton » Sat Feb 09, 2013 10:58 pm

What were they? How are they or perhaps not a poor design?
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Littorio class design flaws?

Post by alecsandros » Sun Feb 10, 2013 12:42 pm

Dave Saxton wrote:What were they? How are they or perhaps not a poor design?
Hello David,

I would note the overly complex design, which put severe pressure on the construction phase.
There were to many innovations brought together in a single ship, and neither of them worked properly. The ships could have served as prototypes for other, more advanced battleships, just as Scharnhorst was for Bismarck...

In practical terms, I would mention the following problems with their design:

= small height of main belt; upper armor belt to thin
= no protection agasinst diving shells
= no protection of stearing gear and forward section
= inadequate con tower protection
= inadequate secondary artillery
= insufficient protected length
= insufficient range
= overly complicated deck protection. The centerline of the ship was heavily protected against free falling bombs, but the margins of the armor deck were thinner and heavy shells could easily perforate it. For example, above the machinery, the ships yielded a triple layer of defense:
- centerline: upper deck 45mm laminate (36+9mm), second deck 12mm, main armored deck 112mm laminate (100+12mm)
- outboard: upper deck 45mm laminate (36+9mm), second deck 12mm, main armored deck 99mm laminate (90+9mm)

I don't know if the laminated upper deck was sufficient to decap incoming shells of 15 and 16" calibers.
The compounded thickness using sqrt formula is ~ 107mm at centerline and 98mm outboard.
This makes the machinery vulnerable between 18 - 25km from most kinds of BB caliber shells used in the war...

= overly complicated torpedo protection system, which also took a lot of internal volume in the ship.
= insufficient built-in redundancy. For example, there was no secondary con tower to control the ship, in the event the forward con tower was lost...
= very low metacentric height (for a battleship)

----

As G&D mention, the Veneto's appeared after preliminary designs in the 18000 - 26500 tons area, which were meant to counter the panzerschiffes and the Dunkerque class battlecruisers. They had limited range and concentrated all their AA and secondary artillery amidships, in order to offer them safety from the blast of the main guns, which were given wide arcs of fire (300*)

Thus, they were maybe comparable only to the French Richelieu's, and perhaps in part to the British KGVs.

Their main strengths were the exceptionaly powrfull main armor array, which was extremely difficult to perforate under normal conditions, the formidable 15" guns, and, in part, their speed (at lower loads).

User avatar
Dave Saxton
Supporter
Posts: 3093
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Littorio class design flaws?

Post by Dave Saxton » Mon Feb 11, 2013 9:00 pm

Perhaps flaws are too harsh of language to use. Trade offs would be better terminology. All designs are really a balancing act of different trade offs. Just commenting on the trade offs they made without saying they are necessarly bad or good:
= small height of main belt; upper armor belt too thin
The belt was shallow but it could not be extended deeper without affecting the functionality of the large TDS. 70mm (vertical) was what the Italians determined was needed to insure de-capping, so it’s easy to see the rationale of using a 70mm homogenous upper belt. It is better than 45mm to insure de-capping and fusing before the shell reaching the main armoured deck.
no protection against diving shells
This potential problem ties in with the shallow main belt. One thing they have going for them in this instance is the large size of the TDS. Diving shells may burst or expend themselves within the TDS region.
= no protection of steering gear and forward section
AoN design, from a purist stand point, would not use any armour weight forward of the citadel. Indeed this was the practice on most AoN designs such as Yamato and KGV and others. Most modern designers dispensed with expending weight for steering gear protection, only German and American designers still considered it important.
= inadequate con tower protection
This is another area were only the Germans and the Americans included significant conning tower protection into their modern designs
= inadequate secondary artillery


It was 6” rather than 5” and it was heavily protected. The turret faces were 11” thick! They seemed to put some emphasis on the importance of the secondary as an anti-shipping (anti- destroyer) weapon.
= insufficient protected length


Compared to German design yes, but it’s about average for most WWII designs with three main turrets. It was better than Richelieu’s or Yamato’s protected length.
= insufficient range
Obviously they were designed for operating mainly in the Med.
= overly complicated deck protection. The centerline of the ship was heavily protected against free falling bombs, but the margins of the armor deck were thinner and heavy shells could easily perforate it. For example, above the machinery, the ships yielded a triple layer of defense:
- centerline: upper deck 45mm laminate (36+9mm), second deck 12mm, main armored deck 112mm laminate (100+12mm)
- outboard: upper deck 45mm laminate (36+9mm), second deck 12mm, main armored deck 99mm laminate (90+9mm)

I don't know if the laminated upper deck was sufficient to decap incoming shells of 15 and 16" calibers.
The compounded thickness using sqrt formula is ~ 107mm at centerline and 98mm outboard.
This makes the machinery vulnerable between 18 - 25km from most kinds of BB caliber shells used in the war...
I don’t know if it could always de-cap heavy shells being a laminate either, but it was of all armour grade materials nearly 50mm. It may have been capable of de-capping heavy shells, and we know the Italians considered de-capping an important element. They also considered yaw. One of interesting things about this arrangement is the 12mm middle deck. A shell beginning to yaw up ward in its rotation will take on trajectory shift away from the normal upon penetrating the next layer. Therefore its likely that there was a net zero trajectory shift before striking the main armoured deck. This factor coupled with probable de-capping would mean that the total effective thickness was probably close to the sum thickness of the upper and main armoured decks net thickness each. Note that because of the distance between the main armoured deck and the upper armoured deck that shells will likely explode before reaching the main armoured deck at battle ranges between 18km and 25km.
= overly complicated torpedo protection system, which also took a lot of internal volume in the ship.
This is often the point of most interest because of the novelty of the design. It had to be large to work as designed, and that is the reason the concept didn’t work well on the re-constructed small battleships. One of the problems was the welding connections of the curved main bulkhead. The welds were not satisfactory, so if the bulkhead yielded then the forces would not be directed into deforming the cylinder.
= insufficient built-in redundancy. For example, there was no secondary con tower to control the ship, in the event the forward con tower was lost...
One area did have superior redundancy compared to most other battleships. The Littorios had backup rudders.
= very low metacentric height (for a battleship)
This was adopted to make them very steady gun platforms. The trade off is of course less reserve of stability.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Littorio class design flaws?

Post by alecsandros » Tue Feb 12, 2013 6:49 am

Dave Saxton wrote:Perhaps flaws are too harsh of language to use. Trade offs would be better terminology. All designs are really a balancing act of different trade offs. Just commenting on the trade offs they made without saying they are necessarly bad or good:
= small height of main belt; upper armor belt too thin
The belt was shallow but it could not be extended deeper without affecting the functionality of the large TDS. 70mm (vertical) was what the Italians determined was needed to insure de-capping, so it’s easy to see the rationale of using a 70mm homogenous upper belt. It is better than 45mm to insure de-capping and fusing before the shell reaching the main armoured deck.
I thought about that when preparing my reply.

But no, I don't see any usefull trade-offs being made in the Littorio's.
They should have opted for another kind of TDS, as the Pugliese system was not only not tried in service (and it proved unsatisfactory during the war), but it also occupied a lot of space, severely limited the main belt's deepness and it had no built-in armor to protect agasint diving shells.

The 70mm upper belt is comparable to the 50mm on Scharnhrost.
They are both useless against even light cruiser fire, not to mention heavier shells. Of course the MAD would protect the deep vitals, but the volume between the MAD and weather deck would be completely exposed.

The secondary artillery was horrible. Not it's protection, but it's effectiveness in combat. 4 triple guns ? Who uses such a thing ?
They were heavy, slow to traverse and to the best of my knowledge not equipped with any kind of radars.

The 7000km range at 14kts is ridicoulous. They could barely go to Gibraltar and back ! And that at 14kts. We see again the downside of having such a wide TDS, which eats up alot of volume whcih could be used for storing something else.

I have my doubts about the 36+9mm upper deck laminate. Why not use a 45mm plate ? Krupp certainly put a lot of emphasis on single-thickness plates, especialy for the upper deck.

A potential problem for them was that they made their yaw trials using only their own APC ammunition.
Th Italian 32cm AP shell was based on a British WW1 design , which was ok for it's time, but not so much for WW2. The cap was easily removed, and the fuze quite unsensitive (IIRC, G. Elder made some research into this and it required the equivalent of 100mm armor to fuze, assuming obliquity of 0*)

There was also the dubious power problem. At one instance, Veneto lost all power in the ship for 2 hours, following a torpedo hit at Matapan. After that , power was restred and the ship limped back to port at 19kts.
I don't know what kind of electrical wirings they had, but to lose all power in the ship after one hit is debilitating. It was probably another problem of redundancy, in this case reserve power... [Littorio's could generate up to 3600 kW. Compare that to Bismarck 8000kW or Iowa's 10500kW.]

User avatar
Dave Saxton
Supporter
Posts: 3093
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Littorio class design flaws?

Post by Dave Saxton » Mon Feb 18, 2013 7:01 pm

alecsandros wrote:There was also the dubious power problem. At one instance, Veneto lost all power in the ship for 2 hours, following a torpedo hit at Matapan. After that , power was restred and the ship limped back to port at 19kts.
I don't know what kind of electrical wirings they had, but to lose all power in the ship after one hit is debilitating. It was probably another problem of redundancy, in this case reserve power... [Littorio's could generate up to 3600 kW. Compare that to Bismarck 8000kW or Iowa's 10500kW.]
The problem of electrical power capacity was reportly a factor in the situation facing Littorio after the torpedo hits at Taranto. The pumping capacity was found unsufficient, but the electrical capacity to support the pumps they had was insufficient anyway. There are also reports of loosing electrical power from shock for both Littorio and Veneto.

Of course the Littorios are not unique among WWII battleships for experiencing electrical problems due to shock or having insufficient electrical capacity. The USN fast battleships and the sinking of the Prince of Wales comes to mind here.

There are also strong parallels to the devastating torpedo hit aft to Prince of Wales and the torpedo hit aft to Vittorio Veneto. Only VV was back under way, albeit with a heavy trim aft, after 10 minutes (according to some accounts).
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Littorio class design flaws?

Post by alecsandros » Tue Feb 19, 2013 8:59 am

Dave Saxton wrote: Of course the Littorios are not unique among WWII battleships for experiencing electrical problems due to shock or having insufficient electrical capacity. The USN fast battleships and the sinking of the Prince of Wales comes to mind here.

There are also strong parallels to the devastating torpedo hit aft to Prince of Wales and the torpedo hit aft to Vittorio Veneto...
I knew it would come to this... :)

G&D also mention that Veneto's pumping rooms were outside the citadel, thus making them quite vulnerable to... anything...

User avatar
Dave Saxton
Supporter
Posts: 3093
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Littorio class design flaws?

Post by Dave Saxton » Tue Feb 19, 2013 10:18 pm

alecsandros wrote: 4 triple guns ? Who uses such a thing ?
The French. Only three triple 6" turrets in the case of Richelieu.
Th Italian 32cm AP shell was based on a British WW1 design , which was ok for it's time, but not so much for WW2. The cap was easily removed, and the fuze quite unsensitive (IIRC, G. Elder made some research into this and it required the equivalent of 100mm armor to fuze, assuming obliquity of 0*)
The British tested some captured Italian 381mm shells and found that their fuzing system worked very well. The shells showed virtually immune to the base slap effects that cause so much trouble for everybody else. The main problem found with the Italian 381mm shells in the British tests was scooping off of horizontal armour due to their relatively sharp nose shapes. This sharp shape also gave them good belt penetration at short and medium ranges and made them difficult to de-cap. (The Italians proofed the 381 shells at 30*).

According to some sources they never had HE rounds for the 381 operational during the war. This would mean that damages done to the enemy were likely from direct hits from AP rather than slinters from near misses by HE, probably not enccountering enough resistance to initiate fuse action.

It looks like the Littorios were about average among their generation overall. Of concern are the dispersion problems, and historically the Veneto never hit anything.

However, we have a bit of paradox here as Littorio's shooting at 2nd Sirte was pretty good. Littorio only expended 181 rounds total and scored direct hits on destroyers. When Littorio first came upon the scene it opened fire at 32km straddling British destroyers, but not scoring any direct hits. There is a parallel to Iowa's and New Jersey's Nowaki chase here. The next time it opended fire was when they tryed to go around the smoke screen. The British recorded a range of 8 miles (14.8km, 17,600 yards) and Littorio scored 15" hits. It also scored hits later when Vian ordered destroyers to attemp torpedo strikes. Was this superior performance compared to Veneto a year earlier due to better shells and propellant, or to advances in firecontrol, or both?

How did Littorio's firecontrol systems compare to say the KGV's or Richelieu's?
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

User avatar
tommy303
Senior Member
Posts: 1528
Joined: Mon Oct 18, 2004 4:19 pm
Location: Arizona
Contact:

Re: Littorio class design flaws?

Post by tommy303 » Wed Feb 20, 2013 12:59 am

The Italian fire control system was, from all accounts fairly good. It was a development of that produced by Hazemeyer in the Netherlands, which itself was a subsidiary of Siemens-Halske of Berlin in much the same way as Solothurn in Switzerland had as a parent company, Rheinmetall-Borsig. The Italians bought an example of the then latest Hazemeyer fire control system in about 1927. Most research and production for German fire control equipment was done in Germany from about 1926 on, while the Dutch subsidiary produced equipment not only for the Dutch Navy but also for foreign buyers. The Italians were happy with the system and it became the foundation for future Italian naval fire control systems. The Germans, however, had moved on to graphic plotting as part of the fire control problem and felt that the Italian equipment was inferior to the latest German equipment in that although a graphic plot was utilized in the latest 1930s systems, they considered it to be too small to be of use.

The curious difference between the shooting of the Littorio and the Veneto is usually attributed by Italian sources as being the result of the two ships having different suppliers for their main battery shells, with one supplier having better quality control than the other. This was one of the evils of the Italian procurement system in that shells which should never have passed inspection found their way into service. In most other navies, shells were selected at random from lots and if the failed, the entire lot was condemned. In the Italian system, the very best and most carefully produced shells were used for test firings and establishing range tables, while those produced for service were of lesser quality.

Their shoulders held the sky suspended;
They stood and Earth's foundations stay;
What God abandoned these defended;
And saved the sum of things for pay.

User avatar
tommy303
Senior Member
Posts: 1528
Joined: Mon Oct 18, 2004 4:19 pm
Location: Arizona
Contact:

Re: Littorio class design flaws?

Post by tommy303 » Wed Feb 20, 2013 3:48 am

As something of an aside, Hazemeyer employed retired Dutch Admiral Mouton from about 1926 as a consultant in its fire control development. Mouton had previously been employed by Barr & Stroud in a similar capacity, so one is left to wonder how much knowledge he imparted to his new employers and which might have found its way to the fire control development team at the parent company, Siemens-Halske.

Their shoulders held the sky suspended;
They stood and Earth's foundations stay;
What God abandoned these defended;
And saved the sum of things for pay.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Littorio class gunnery problems

Post by alecsandros » Wed Feb 20, 2013 6:29 am

Well, dispersion and gunnery problems were notorious for the class, but I wouldn't consider them "design" flaws.

They represented, however, severe production problems...
I have a photo o Veneto's salvo splashes falling around HMS Gloucester. They are 3-gun salvos, with apparent dispersion 3x the length of the cruiser... Reported firing distance was 22km.

The various quality of 381mm shells was already pointed out by Tommy.

Another aspect was the lack of delay coils for main battery guns, which were introduced, according to Bagnasco, in mid-1942 for Littorio and Venetto.

Yet another problem came from the unreliable RPC system, which allthough quite ambitious (it featured remote automatic control for both training of turrets and elevation of guns) it broke down all the time, and the crews had to rely on the older, manual-input methods...

The absence of radar for up until Oct-1942 was another handicap for the Italian battleships, and a severe one in the context of the Mediteranean campaign.

User avatar
Dave Saxton
Supporter
Posts: 3093
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Littorio class gunnery problems

Post by Dave Saxton » Wed Feb 20, 2013 2:45 pm

alecsandros wrote:Another aspect was the lack of delay coils for main battery guns, which were introduced, according to Bagnasco, in mid-1942 for Littorio and Venetto.

So much like Richelieu and Jean Bart.
Yet another problem came from the unreliable RPC system, which allthough quite ambitious (it featured remote automatic control for both training of turrets and elevation of guns) it broke down all the time, and the crews had to rely on the older, manual-input methods...
So much like the USN automatic systems.
The absence of radar for up until Oct-1942 was another handicap for the Italian battleships, and a severe one in the context of the Mediteranean campaign.

I believe Littorio had Gufo radar by March 1942, but Veneto did not until 1943. Was radar ranging a factor in Littorio's better shooting? Gufo did not have lobe switching so blind fire wasn't possible. It should be pointed out that Allied radar was slower coming of age in the med than many may realize. For most RN ships deployed to the Med they had to wait until 1942 to receive any radar as well. The radar Valiant used in March 1941 was Type 79(its only radar at the time) and the battle range was only 7,000 yards.

What about night fighting optics? Did the Italians battleships have any or were they like the USN fast battleships lacking in this aspect?
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Littorio class gunnery problems

Post by alecsandros » Wed Feb 20, 2013 4:51 pm

Dave Saxton wrote: So much like Richelieu and Jean Bart.
Indeed, and a nice question would be - how would those 2 battleship classes perform one against the other ?
(My bet would be that they would expend their ammunition without scoring hits at all :D )

So much like the USN automatic systems.
Hmm, maybe...
However, at least parts of the automatic fire contorl system functioned correctly in the US battleships - and that was the integrated radar feed...
I believe Littorio had Gufo radar by March 1942, but Veneto did not until 1943. Was radar ranging a factor in Littorio's better shooting?
Well, Bagnasco mentions
"Littorio received her first experimental radar set, the EC3/bis Gufo, in Sep 1941. An improved type, EC.3/ter, replaced it in the first months of 1942, only becoming fully operational in Sep 1942. Littorio received a second EC.3/ter set in the summer 1943. Same sets were installed on Venetto in June 1943, and on Roma in Aug 1943".

I always come back to Littorio's struggle agaisnt Vian's destroyers. It's true the weather was bad, but still... a single, non-detonating hit, and a near miss... from 181 shells fired at ranges of 5-8km...
I doubt it was dispersion alone... they probably had ranging problems as well...
What about night fighting optics? Did the Italians battleships have any or were they like the USN fast battleships lacking in this aspect?
I doubt they would have anything like that. They feared the night !

User avatar
Dave Saxton
Supporter
Posts: 3093
Joined: Sat Nov 27, 2004 9:02 pm
Location: Rocky Mountains USA

Re: Littorio class design flaws?

Post by Dave Saxton » Wed Feb 20, 2013 8:44 pm

We don't know how many of those 181 rounds were expended at battle ranges of about 35,000 yards. It scored hits at 17k. South Dakota and Washington, east of Savo Island, expended about 140 rounds in exchange for zero hits against a cruiser and destroyers at sub 18k ranges and with subdued seas. Of course 42 of those rounds were fired at a phantom radar contact.
Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Littorio class design flaws?

Post by alecsandros » Thu Feb 21, 2013 6:20 am

Dave Saxton wrote:We don't know how many of those 181 rounds were expended at battle ranges of about 35,000 yards. It scored hits at 17k.
What hits ?
Kingston was hit at 5km, during the torpedo run.
In return, the British destroyers hit Littorio twice with their 120mm guns.

alecsandros
Senior Member
Posts: 4349
Joined: Wed Oct 14, 2009 2:33 pm
Location: Bucharest, Romania

Re: Littorio class design flaws?

Post by alecsandros » Thu Feb 21, 2013 9:18 am

Dave Saxton wrote:
The British tested some captured Italian 381mm shells and found that their fuzing system worked very well. The shells showed virtually immune to the base slap effects that cause so much trouble for everybody else. The main problem found with the Italian 381mm shells in the British tests was scooping off of horizontal armour due to their relatively sharp nose shapes. This sharp shape also gave them good belt penetration at short and medium ranges and made them difficult to de-cap. (The Italians proofed the 381 shells at 30*).
WW1 - era projectiles were easily decaped... especialy if they were very pointed...

I'll try to find my references to Italian 381mm APC shells manufacturing...

Post Reply