I've heard of this before, what were the specifications compared to the composite scheme? Was the belt meant to be angled, and was it meant to be wider than the very narrow armor side on the Littorio? I heard that the Littorios' side armor was said to be equal in weight to around a 415mm side, while being much more effective, so it seems like the extra weight savings from a single plate might be used somewhere else.
I'm not familiar with any published information that gets that granular on the prior scheme. The 35,000-ton ship (3x2 406mm guns) from the 1928 design had a 350mm belt, but was probably not angled beyond the natural curvature of the hull - earlier arrangements of the armor on the
Littorio-class that was multi-layer but not yet composite includes vertical armor plates, for example. Really, much was changed in the armor scheme of the
Littorio-class over the course of the design process.
Also, on the topic of fire control, how good was Italian battleship fire control? It seems it was so bad that the myth of "bad Italian shell quality" appeared to explain the terrible shooting accuracy.
(Also this goes for Italian cruiser and DD fire control. I've heard that Italian fire control was worse than the Germans' equivalent systems, which in turn scored a lower percentage of hits than British destroyers)
The 'bad shell quality' question is related to the dispersion of the fall of shot in a salvo, which is generally a separate issue from shooting accuracy.
'How good' really depends on which foreign systems you're comparing it too, and also what aspects specifically. This is also not exactly uniform across ships. For example, when rebuilt, the
Conte di Cavour-class used largely the same computer system as had gone into most of the modern Italian cruisers (
Giussano-class excepted) and had broadly similar performances - though obviously with different stored ballistics.
This meant that their fire control systems were broadly inferior to those of the
Littorio-class, which were a generation beyond that system, and to that of the Duilio-class after their reconstruction. The
Duilio-class used largely the same fire control system as the
Littorio-class save for the secondary battery (152 and 135mm batteries), though they did not have the same stabilization systems for the main and secondary batteries (only for the 90mm battery).
Broadly speaking, Italian fire control systems were peer with those of the other major European naval powers. The computer systems themselves compared favorably, while stabilization systems tend to be more variable across different classes between the major powers. Their optical systems were high quality and were very competitive with their contemporaries - cutting edge in some cases - though at the same time, the German optical industry was more advanced and here the shortcomings of the Italian optical industry were more pronounced (most notably, that the Italians lagged in anti-glare treatments, which the Germans started introducing in 1935).
Generally speaking, Italian fire control systems seem to have held an advantage over their British counterparts in daylight actions. Both the British and Italians picked up on the fact that when both sides were engaging, the Italians would usually be able to straddle first and were generally accurate, but had more dispersed salvoes - especially when forced to maneuver. The British, meanwhile, usually had fairly tight salvoes but often struggled to find the range as quickly. In general, the record of most Italian cruisers and battleships was fairly good, with straddles often coming early at fairly long ranges. The
Littorio-class stands out in particular in this regard, both for straddles at extreme ranges (at Cape Spartivento and 1st Sirte), and also managing to get a decent number of straddles in actions that were shorter ranged but in much worse weather conditions, where the enemy was making heavy use of smoke and maneuver (the Action off Gavdos and in particular, 2nd Sirte).
With that said, older ships with older systems also clearly struggled more. Among the cruisers, the
Giussano-class large scouts and the
Trento-class heavy cruisers stand out in particular.
The
Giussano-class were built before the major series of modern fire control systems were fully developed, and as such they used what could perhaps be described as a less developed or 'prototype' system that was also used on the Navigatori-class light scouts. Without wanting to get bogged down in two many specifics, this was a generally inferior system in several regards, but perhaps most consequential was the fact that the initial version of the Gimetro used in this system did not automatically measure the angle of heel of the trunnions. For a class with the kind of stability issues of the
Giussano-class, this heavily limited what kind of sea conditions they could accurately shoot in. The Battle of Cape Spada is a perfect example of this - the sea conditions limited
Bartolomeo Colleoni and
Giovanni delle Bande Nere to a maximum effective gunnery speed of 32 knots, only moderately faster than the top speed of the cruiser pursuing them (HMAS
Sydney, then capable of up to 30 knots) and her accompanying destroyers (32 knots). Had they foregone trying to engage with their guns and just ran, they would have been able to open the range somewhat faster (their top speed by that point in time was about 33-34 knots).
The
Trento-class were built even earlier - the first modern Italian cruisers built in the 1920s - and came before almost any part of the modern domestic Italian fire control system was ready. Thus, their primary fire control system was instead a license-built (by Galileo) copy of a Barr & Stroud fire control system, with only the controls for her secondary battery eventually being a more domestic system. Their main rangefinders were likewise license-built copies of Barr & Stroud systems. The fire control system itself worked on substantially different principles from the systems the Italians were developing for themselves and ultimately was a soundly inferior system. This fire control system similarly suffered in regards to handling rougher seas, and to boot, the performance of the rangefinders were greatly lacking by WWII. The AAR for Operation Guado complains about the performance of these rangefinders at length, versus those employed by
Bolzano (and the
Zara-class).
Trento's primary director rangefinder - a license-copy of a Barr & Stroud 5-meter coincidence model - actually never gave any good ranges at all in the chase of the British cruisers, due to the lighting conditions - only the 3.66-meter rangefinder for scartometry managed this, and could only do so from 20,000 meters or less due to the small base length.
Trieste's director had a 5-meter Zeiss coincidence rangefinder, gave better performance, but
Bolzano's (5-m, domestic) was easily the best and was giving ranges out to 28,000 meters.
The
Zara-class were the first cruisers to employ the main production version of the RM Type 1 fire control system, which would also equip
Bolzano, the
Cadorna-class large scouts, all the 152mm light cruisers, and the
Conte di Cavour-class, as rebuilt. Though far from flawless, this system performed well. Probably the greatest issue was that which was related to stabilization and the systems by which gun orders were transmitted to the guns, which was largely FTP (Follow-The-Pointer).
In particular, the technical report for the heavy cruiser divisions following Capo Teulada/Cape Spartivento describes how the systems designed to correct for trunnion displacement were not accurate enough and not rapid enough in their corrections to avoid firing solutions being disturbed by own-ship maneuvers when the cruisers were turning hard to avoid enemy fire. This is in part relating to stabilization arrangements (which we know would have been particularly poorer in
Trento and
Trieste, versus the other four heavy cruisers at that action), but also relating to the transmission systems as well. This latter one is one of the core issues identified as being at play with dispersion issues by pre-war investigations, at least on older cruisers - too much 'slack' in the FTP systems causing delays in corrections that lead to aiming errors. Though, it is worth noting later systems seem less prone to this error - the FTP systems of the
Cavour-class, when rebuilt, was newer than those on the heavy cruisers and did not suffer the same issues (though, they did have dispersion issues with the 320/44 guns that seems to have been inherent to the guns themselves). I have no idea what the
Cadorna-class were fitted with, but later light cruisers had better systems, with the
Abruzzi-class being particular standouts. The
Littorio-class and Captiani Romani, meanwhile, were a generation beyond these other ships in fire control systems.
This is, it is worth noting, very consistent with British observations of Italian heavy cruiser firing at Cape Spartiveno - initially very accurate, but deteriorating once they were fully engaged by British guns, with the spread becoming 'ragged'.
And I feel it is worth pointing out that, if nothing else, the Italians certainly shot no worse than the British at that action. The Italian heavy cruisers (6) scored three hits (on two cruisers) from 658 rounds fired, and British cruisers (one heavy, four light) likewise scored three hits (all on one destroyer) from over 3,200 shells fired - a hit rate of 0.5% versus 0.1%. The Italians did have an advantage in fighting in a range band more favorable to 8" guns rather than 6" guns, but overall still managed a hit rate five times higher. If anything, what really stands out is that the Italians were far too in favor of deliberate, aimed fire, which reduced their overall ammunition expenditure and thus opportunities to hit. The British were always vastly more liberal with ammunition expenditure, and ultimately the more shells you fire, the more chances you have to hit.
On destroyer fire control specifically - unfortunately I lack detailed sources to really go in depth on this. The Italians did place a big emphasis on putting director control on destroyers, even backfitting many older destroyers with relatively heavy directors. The wisdom of this was debatable given the limited effectiveness of destroyer gunfire at longer ranges and the overall impact on topweight it had, but at the very least the daylight systems worked decently well. Perhaps the most extreme example is the last stand of
Espero, where this older Italian destroyer with a collective four 120/45 managed to somehow score the first hit in an action against five British light cruisers massing forty-eight 6"/50's.
Where things really fall apart is at night, where most of the destroyer gun actions happened. Italian destroyers did not use their regular fire control system for night combat, but rather used rapid-reaction 'detector' devices on the bridgewings for transmitting angles of train to the APG (General Aiming Device), which then sent train orders directly to the guns (instead of the fire control center).
This reflected Italian night combat doctrine, which, while not ignoring gunfire (and Italian destroyers went into the war with flashless charges and tracers for main gun ammunition), put the torpedo above the gun for night combat due to the more decisive nature of that weapon system, and the general limits of what destroyer gunfire could achieve. It was only after the experience of the early war - from the summer 1940 to spring 1941 - that the Italians started making moves on upgrading the destroyer gun fire control systems. Orders to install full night APG's (like those that could be found on battleships and cruisers) came in April 1941, though the limited production rate of these systems meant that installations only started in March 1942. Destroyers refit prior to that had temporary systems installed, pending delivery of the night APG's.
As such, one can clearly see how the functionality of the nighttime fire control arrangements were reduced versus the 'normal' systems. I am not familiar with how this compares with German destroyer fire control systems.
If we are talking about lower hit rate in general, versus British destroyers - this is likely a figure shaped by most of the actions fought. In the early war, Italian destroyers did better as they generally knew where the British were. Offensive action by flotilla units at night was a part of Italian doctrine and accordingly up through April 1941, out of eleven night actions the Italians fought with the British, they instigated eight of them, and the British only three. Results were heavily mixed, mostly either inconclusive actions or superior British forces beating off attacks by torpedo boats. From May 1941, however, the center of gravity of the war more firmly swings to the convoy effort, and the vast majority of night actions fought are those started by the British, attacking Italian convoys.
Italian night combat doctrine before WWII made no provisions for scenarios where Italian forces were defending convoys from sudden attacks at night, and even the initial round of revisions to night combat doctrine in the spring of 1941 did not address this. This was a serious issue, as for the rest of the war Italian convoys had to cope with British cruiser and destroyer forces launching sudden ambushes at night against Italian convoys. Often the result was that the Italian escorts were incapacitated by the first salvoes of British gunfire that provided their only warning (especially once the British began using radar). This was really a scenario where the Italians needed radar and a CIC arrangement to respond to such attacks - but they lacked both of these things. To be fair to them, the CIC itself was something that the Allies did not really develop until late 1942, which was far too late for the Italian war effort - but that is besides the ultimate point. Night actions are usually decided by the side with the initiative and who fires the opening salvo - and thus, the offensive agent. And the British were almost always the ones attacking from May 1941 onwards.
With how these night actions developed, very often it turned into 'British CLs/DDs pump many 120-152mm shells into burning hulks at very close range and leave', while on the Italian side there is often only a limited reaction from those units not incapacitated in the opening minute of the fight, and often poorly directed as they're not sure exactly where the British are. As one can imagine, this probably does very flattering things for the overall hit rate the British managed, and the opposite for the hit rate of Italian destroyer guns.
You forget that the Italians also had knowledge (albeit false knowledge) of the German shipbuilding programmes, which called for 40k ton battleships armed with 406mm guns. The Italians also knew that the French would try to respond to the Littorios with their own 35k ton design, and that they might go for 40k tons in the future.
Thus, for the Roma/Impero pair and maybe for the possible third pair as well, a 406mm design was considered.
Correction here - the larger 406mm design was
not considered for
Impero &
Roma. As I laid out in my
first post in this thread, the studies for long-range procurement in 1937 only considered the questions of repeat
Littorio's and the reconstruction of the
Duilio-class, both of which were ultimately acted upon. This was to allow the creation of a core of two homogenous divisions for the fleet, one of the modern fast battleships, and one with the rebuilds.
The inclusion of the larger 406mm design in any programs only really comes forward twice. The first time is in the context of the 'Programme B', the longshot of the 1935/36 'breakout fleet' hypothesis that called for a total of nine battleships. The more realistic Programme A of the 'breakout fleet' did not touch on this type at all, and its six battleships would have only composed of three
Littorio's and three rebuilds.
In the context of the potential long-range program of 1939-45, the concept was raised again, but was far from guaranteed - as mentioned before, Admiral Somigli, who had just been appointed Deputy CSMM (CSMM = Chief of Staff of the Navy) in July 1939, was in favor of the larger design, but Cavagnari (the CSMM) instead wanted a third pair of
Littorio's,
if any new battleships were to be built at all. The events of 1939 killed any further discussion on this topic anyhow, and even the actual authorized 1939 program (which did not call for any battleships) was not fully executed.
---
When talking about the impacts of further European programs on battleships, it is worth bearing in mind the Italian attitude towards these programs at the time. As of 1939, the Italians were generally favorable towards battleship size not escalating beyond 40,000 tons, which was a size they could more easily manage and that would not devalue the
Littorio-class excessively.
They, for example, already knew of the
Lion-class battleships, the first pair of which was already programmed in 1938 - but did not find it excessively worrying as these were 40,000-ton units and thus on equal footing with the Littorio-class. The
Littorio's 381/50 had been deemed acceptable in the first place because they were judged to provide comparable hitting power to a 406mm gun, and the armor scheme of the ships had in general been designed with resisting 406mm guns in mind. The
Lion-class would certainly at the very least equal a
Littorio, but were not a huge issue by themselves and were vastly preferrable to the British procuring 45,000-ton ships. They also knew the French were not in favor of building battleships over 40,000 tonnes, and at present were only building '35,000-ton' types.
Likewise, they did not expect the Germans to present an issue in size escalation because the Germans were lying through their teeth to the Italians as to the size (40,000 tons rather than 52,600 tons) of the H-39 battleships, and the numbers they planned to procure.
With all of these together, Cavangari had a very compelling argument as to why Italy should not seek to build anything beyond a third pair of
Littorio's, if any new battleships should be built at all in the short term (again, there were other pressing priorities in 1939 as laid out in my first post).
The start of the war naturally killed any question of further battleship construction, but it is actually worth noting that when the French did ultimately come out with their 1940 naval program in April 1940, they did limit themselves to just procuring a 40,000-ton ship with nine 380mm guns as a response to the H-39-class. This was the smallest of the three designs they had studied (the others being 42,500 tons and 45,000 tons) and was based on their own intelligence estimates of the H-39's, which matched those the Germans reported to the Italians (40,000 tons with 406mm guns).
Thus, even if the war had not erupted when it did, as of mid-1940, the British and the French would still have been ordering only 40,000-ton battleships (6 and 2 as of 1940, respectively) that, from the Italian perspective matched the real characteristics of the
Littorio-class and would not have forced them to move to larger capital ships.
Personally speaking, the only real route I see for the 45,000-ton design coming forward for procurement is a scenario where the war does not start when it does, and that French intelligence gets a more accurate read on the size of the German battleships. If that can compel the French and British to move to larger capital ships sooner, than the RM may finally be forced to accept that they would need larger capital ships to match such Allied warships, given there would be no way to put that genie back in the bottle.
