Alberto Virtuani wrote: ↑Sat Nov 10, 2018 7:37 am
Hi GiZi,
It's correct, the excessive spread at Gaudo, from distances varying form 23000 to 25000 meters was of over 500 m, at least looking at this photo (first posted by Alec) of Perth (the straddled ship has 2 funnels and the camouflage identifies her as Perth, not Orion nor Gloucester, proving that also Perth was, at least shortly, fired at too). Just one minor precision: Vittorio Veneto at Gaudo fired 94 shells in 29 salvos (out of 105 ordered shots, due mainly to a problem in the left gun of turret 1, which lost 6 shots out of the 11). Visibility was very bad that day (misty) and VV had to change target several times due to smoke, this also explaining why no hit was scored at all, but dispersion was indeed a real problem anyway. (data from VV GAR).
Figura_3.jpg
Vittorio Veneto at Gaudo in 1941 was firing mainly one turret salvos (three guns), some 2 turrets salvos (6 guns) and possibly some broadsides too, therefore I'm not sure it's completely correct to compare with Richelieu semi-salvos fired with alternate 2 guns per turret (if I understand correctly the way the ship fired at Tricomalee in 1945).
However, the main dispersion problem for Littorio's was always linked to ammunition low quality, not to the guns being too close (this was the problem of the Italian 8" cruisers). The interference of the guns may have affected it in some way of course, but this was never identified as the main root cause.
After the battle of Gaudo, due to Adm.Iachino complaints about the dispersion, the controls over the ammunition were made more strict and I would agree with you that the dispersion reduced to the one in 1940 and the gunnery trials of both VV and Littorio up to the end of their career confirm that. Of course, being in wartime, we cannot know for sure whether these enhancements only impacted the "selected" tested ammunition or the whole provision for both ships.
Bootm Line, I would consider Littorio's guns (after reduction in muzzle velocity) less dispersive (and more powerful) than Richelieu's ones by design, once all ships were using good and uniform ammunition. Littorio's ships main shortcoming was their very limited range (not considered so important for their Mediterranean only usage).
I don't know whether delay coils were ever installed on Littorio's. I don't think so, as neither E.Bagnasco (Littorio Class Battlships) nor Iachino (in his several books on WWII and especially on Gaudo/Matapan) ever spoke about them. Iachino wrote at length about the "corrective" actions derived from Gaudo (and Matapan...) action.
Bye, Alberto
Hello Alberto,
Interesting, I had taken the figure of 91 shells fired from Bagnasco's
The Littorio Class, for a total of 102 shells ordered to fire in 29 salvoes (Meanwhile, Vincent O'Hara in
The Struggle for the Middle Sea, which describes 92 shells fired with 11 misfires, but this obviously incorrect).
The conditions at the battle were not the best for shooting, which I do agree hampered
Vittorio Veneto's gunnery, but at the same I tend to not consider it to be a large part of why she failed to hit - the RM Type 4 was an excellent fire control system, and even if it was only relying on optical inputs it still proved very accurate in spite of this - four months before she had very accurately targeted the cruiser
Manchester at very long range and although only firing 7 salvoes managed to straddle early on. Bagnasco gives the range as 28500 to 32500 meters, although O'Hara quotes Campioni as stating he opened fire at a range of 32,000 yards (29260 meters) and ceased fire at 40,000 yards (36576 meters).
In VV"s gunnery action of Operation Gaudo, she opened fire at
Orion at a range of 23000 meters, and her first salvo was an over - Bagnasco describes it as a broadside (English-language text reads as:
"By way of response, at 10.57 Vittorio Veneto opened fire on Orion which was the leading British ship, with all her main gun turrets, at a range estimated at 23,000 metres."), but O'Hara describes it as a 6-gun salvo. Despite this, she is described as quickly finding the range, and
Orion received 10 accurate salvoes before VV ceased fire for 3 minutes (because of the misfires in turret No.1). Fire was resumed against the
Gloucester, exposed by the smoke screen, who maneuvered violently as destroyers moved to covered her with smoke, and again VV frequently straddled her. However, with incoming aircraft, and being unable to accurately continue to spot the fall of her shot, VV was forced to cease fire at 25000 meters. By all accounts, it seems that in spite of the weather conditions, smokescreens, and maneuvers of the British cruisers, she was extremely accurate in her targeting of the cruisers - but what help her back from hitting was the dispersion of her shells.
As far as the ship in the picture - while I agree it is the
Perth pictured, most likely the salvo was one of VV's overs, and not any targeting of the Australian ship. The shells all appear to be off her starboard side, rather than straddling her, and not only do most accounts of the action only describe
Orion and
Gloucester being targeted, but the image's caption also describes the salvo as being an over of
Orion rather than being aimed at
Perth
The Trincomalee firings that resulted in 450m dispersion were 'half-turret' salvoes - as each quadruple turret is arranged as two 'twin' turrets put together, fire control procedure treated each pair of guns in the turret halves as their own 'turrets'. A 'half turret' was essentially this;
You're right in that it's not very comparable - whereas
Richelieu's dispersion issues lie entirely in the fact that the barrels in each half-turret are too close, the problems affecting the
Littorio-class had little to do with this, and while delay coils would've likely helped in combating dispersion, it would only be marginal - as you said, the issue had more to do with quality control. The exercises later in the war don't seem to show great dispersion being a problem again, nor does
Littorio's guns in action (while Iachino had many complaints after 2nd Sirte, dispersion of the 381mm guns was not among them, at least as far as Bagnasco reports).
Overall, I do agree that the guns of the
Littorio-class were overall more accurate and harder-hitting than those of
Richelieu. The
Littorio's as a whole I think were good ships, and although some shortcomings are certainly due to design (for example, diesel generators being outside of the citadel, and the considerably thinner deck armor over the machinery spaces), I think many of their biggest problems were things shared by the Regia Marina as a whole. Lack of range was common with many ships (because, as you said, Mediterranean usage), but also the lack of radar until so late in the war was of considerable disadvantage, and perhaps more than anything else the lack of cooperation between the Air Force and the Navy - time and time again the admirals at sea were let down by the inability of the Regia Aeronautica (or the Luftwaffe counterparts, especially in regards to their willingness to cooperate) to give effective reconnaissance, or effective air cover, to the fleet.
If Iachino never mentioned delay coils, I think that means its more likely than not they were never installed. I've never had a chance to read any of Iachino's books, so I'm curious - what did the corrective measures entail, at least in regards to dispersion of the guns? I know there was some re-shuffling of powder, and more strict quality control put in place, but any details on that, or other measures? And does he place the blame on quality of shells, or propellant charges?
alecsandros wrote: ↑Sat Nov 10, 2018 12:00 pm
Emilio Bagnasco wrote in "Littorio class: Italy's last and largest battleships [...]" several commentaries concerning Littorio class dispersion issues. He also annexed a performance table for OTO and Ansaldo 381mm/L50 guns (which was first posted on Kbismarck by Alberto, using an article from Storia Militare, written in Italian , IIRC).
In short, during the firing trials of 1939-1940 and 1940-1941 (which were the last ones), dispersion of salvos was around 200meters to 250meters (for 3-gun salvos, all 3 guns from the same turret), for firings between 18 to 20km, and 350 to 500meters for firings between 20 to 22km (presumably for the same type of 3-gun salvo firing).
Comparing it to the firings described in Jordan/Dumas French battleships [...] for Richelieu in 1945 (270meters for 1-gun per turret for a total of 2 guns/ship and 450meters for 2-guns per turret, for a total of 4 guns/ship, range 16 to 25km) , we see that the size of the dispersion was comparable , between the 2 battleship classes*.
Italian doctrine of firing the main battleship guns, according to Bagnasco, was to fire 3 x individual turret salvos (3 salvos of 3 guns each, 1 salvo from each turret, with each turet firing on slighltly different coordinates then the other 2, in an attempt to obtain correct range and bearing of target), observe fall of shot of the 3 salvos, then adjust elevation and train, fire again in the same method , etc. After target had been correctly ranged, firing for effect was ordered, meaning firing with all guns at maximum rate of fire (allthough it is not clear if that implied 9-gun salvos or each turret of 3 guns firing by itself as soon as it was ready to fire).
* It is interesting to observe that both battleship main guns had their muzzle velocities reduced during active service , due to excessive barell wear and dispersion of shots. Littorio class was designed to fire a 870m/s shot, later reduced to 850m/s. Richelieu was designed to fire at 835m/s, later reduced to 785m/s, later slightly increased to 800m/s.
In any case, the 850m/s mv of the Littorio's was a far more powerfull weapon then the 800m/s of the Richelieu's, and , factoring in the armor layout, the Italian battleship appears as far more resilient to RIchelieu's armament then viceversa.
Indeed, that table is one of the references I've been using. Given the basis of Italian gunnery was on turret salvoes, I think it's safe to assume all recorded figures are for 3-gun turret salvoes. I do wish more information was provided in regards to number of rounds/salvoes fired, and what the conditions of the target was (as hit rates are listed). The pattern from the figures is somewhat difficult to use due to how wild
Vittorio Veneto's figures are. Whereas
Littorio's dispersion remains largely consistent, having seen 315m at 17.4 km, but about 360m at 18.8 to 22.5 km, VV's is all over the place - the longest-ranged figure (21 km) is the most accurate at 267m, but closer to
Littorio's figures for another exercise (slightly greater dispersion at slightly greater range than her sister's 17.4 km shoot) - and then the 'median' range of VV's shoots, 20 km, sees a massive jump over any other figure. It should be noted that both battleships experience increased dispersion from previous years going into 1941, but VV's increase is a far more drastic doubling of the spread. Coupling this with her far greater dispersion in the Battle off Gavdos compared to Cape Spartivento, it seems she took on her infamous ammunition load in-between these points - as the values for the 1941 shoot, and Operation Gaudo, are all outliers compared to other figures (the only ones in excess of 2% of the range).
I think you may be confusing the numbers I described for
Richelieu. The 270-meter figure was for a single gun, the same gun firing 8 rounds and then measuring the dispersion - not two guns from different turrets or half-turrets. The 450-meter figure is of a single half-turret, so only two guns firing, both being of the same half-turret (as shown in the image above). The use of a single gun was only for the purposes of a test, as standard firing procedure used half-turret salvoes. Re-reading some sections of the Jordan/Dumas book, it seems four-gun salvoes were not full turret salvoes, but rather the firing of two half-turrets from different turrets. So, with the exception of VV's poor shooting in early 1941, who's turret salvoes were worse than the dispersion experienced by the half-turret salvoes of the 380mm Mle 1935, in general the 3-gun salvoes of the 381/50 M1934 seems to have been the tighter spreads.
As far as your description of Italian Fire Control Procedure, that's the same as I understand. As far as I know there was never consideration for full broadsides, as fire was only done in 3-gun or 6-gun salvoes - most likely the fire-for-effect phase would've involved the British-style 'fire as soon as she loads' style.
The note that both ships had velocity reduced is an interesting one, but it should be noted they were for different reasons. The lower of velocity on Italian guns was directed towards reducing dispersion and barrel wear (which also reduces dispersion over time). For the French 380mm guns, this had more to do with shell design and availability of charges. The initial combination of OPfK Mle 1935 shells and SD21 charges resulted in the detonation of shells in the barrel because of the gas cavities in the back of the APC, so thus the SD19 shells of the
Dunkerque-class's 330mm guns had to be used, which caused the drop in velocity (from 830mps to about 785 mps). When the United States made shells and charges for the French, these were loaded, and the new OPfK Mle 1943, when used with the American charges, had velocity of 800mps.
However, as it turned out, the American charges were not very compatible with the French replenishment system, which lead to bags being frequently breaking - which would shut down the turret for the half-hour required to sweep it clean. As a result,
Richelieu continued to rely on the SD19 charges more often than not (three quarters of her charges were SD19), and in the event of combat against enemy ships, the crew kept an emergency stash of the original SD21 charges she was meant to operate with! Her muzzle velocity, ultimately, ended up being variable as a result of the three different charges kept on the ship.
In regards to armor protection - in my personal opinion I think that
Littorio was the better protected of the two, especially against each other's guns, and I dislike the practice of putting so many eggs in the same basket (all main guns being in just two turrets) - but to give credit where it is very much due, the deck protection of the French battleship was very good. While
Littorio's magazines were very well protected (effectively 42mm upper deck/70mm hull side to decap shells before hitting a laminated deck of 157mm effective thickness), the machinery spaces used a 100mm OD plate instead of 150mm as on the magazines, and I suspect would be quite vulnerable to the guns with heavier shells emphasizing deck penetration at long range - such as the American 16"/45 Mk.6.
Richelieu has a 150mm deck over her machinery, and a 40mm splinter deck below that to defend against any resulting splinters, which is likely much more resistant (although still penetrated by the 16" Mk.6 in combat at Casablanca). That being said, against the modern 380/381mm guns of the European battleships, either battleship has plenty enough deck protection, as all of those guns tended to not perform particularly well against deck armor.