Medium-caliber and large-caliber naval guns
From another perspective, the existence of battleships is to provide a platform for various types of naval guns. On a modern battleship, large-caliber main guns will directly participate in the attack on enemy ships, while small and medium-sized machine guns and machine guns on the ship can also be used for air defense and counter-thunder.
In terms of naval guns, the Italian Royal Navy believes that naval guns with a caliber greater than 203 mm can be called large-caliber naval guns, 120 mm to 203 mm are medium-caliber naval guns, and less than 120 mm are small-caliber naval guns. In terms of air defense weapons, those greater than 13.2 mm are heavy air defense weapons, and those less than or equal to 13.2 mm are classified as light air defense weapons. The regulations were such that in fact, in the late 1930s, when the 13.2mm anti-aircraft machine guns were completely replaced by 20mm anti-aircraft machine guns, the Navy still considered the 20mm anti-aircraft machine guns to be light anti-aircraft weapons; other documents from the same period also showed that the 203mm naval guns on heavy cruisers were often classified as large-caliber naval guns.
As mentioned in the previous article of the series, the "Vittorio Veneto" class battleships will eventually be equipped with four calibers of naval guns (381mm/152mm/120mm/90mm) and two calibers of machine guns (20mm/37mm). Among them, 3 triple-mounted 381/50 turrets constitute the main gun group, and 4 triple-mounted 152/55 turrets constitute the secondary gun group, whose main purpose is anti-ship; anti-aircraft firepower is provided by 12 single-mounted 90/50 dual-purpose guns, 20 Breda 37/54 machine guns and the original 16 Breda 20/65 machine guns. Considering the needs of night battles, the "Vittorio Veneto" class also carries 4 old Japanese 120/40 guns, which are specially used to fire flares during night battles-almost only play the role of night battle lighting. In fact, similar ships of other navies, including the Italian Navy, rarely carry guns specifically for night battle lighting. Therefore, if there is a dual-purpose gun with a caliber of 120~140 mm that can be carried on the "Vittorio Veneto" class battleships, the layout of its secondary guns and anti-aircraft guns will be greatly simplified, and the efficiency of air defense and anti-ship will be greatly improved.
This type of naval gun has appeared in the 1930s, such as the 127/38 type used by the US Navy and the 133/50 type used by the British Navy, but the Italian Navy has never had it. The Italians also realized the strategic significance of this type of naval gun, which can be used as a secondary gun and anti-aircraft gun for battleships, or as a main gun for destroyers. Unfortunately, the development requires time and resources to break through the technical bottleneck, and it is unrealistic to develop and produce it in a short period of time. The Italian Navy once tested placing several 120/27 anti-aircraft guns on a gun mount with a maximum elevation angle of 85° and using semi-fixed ammunition, but the results were not satisfactory. Subsequently, it took over the test of the 120/42 anti-aircraft gun provided by Ansaldo, but there was no result until the Navy decided to develop a more modern 135/45 gun as ship-borne anti-aircraft firepower. When the project began to show results, the war was over. On the other hand, if medium-caliber anti-aircraft guns want to exert efficient firepower in air defense operations, they need special directors. Italy’s technical level at that time could not produce directors that met performance requirements.
Among all the ship-borne weapons of the "Vittorio Veneto" class battleships, the 381/50 main gun and the 90/50 main anti-aircraft gun are exclusive to this class. The 152/55 type as a secondary gun is actually the main gun of the "Garibaldi" class light cruiser. The 37/54 type and the 20/65 type have also been used on large warships and torpedo ships for many years, and the 120/40 type is disassembled from some old ships.
The 381/50 triple gun 381750 type is the largest caliber domestically produced naval gun in Italy’s history. The most powerful, in 1914 Ansaldo-Schneider planned to produce the 381/40 naval gun for the "Caracciolo" class battleships. However, the battleships of this class were never completed, but Ansaldo accumulated some experience in the production of large-caliber naval guns. In 1934, the Italian Navy designated Ansaldo to manufacture naval guns for all "Vittorio Veneto" class battleships, so the "Ansaldo 381/50 1934" came into being. Of course, as a cooperative supplier, O.T.O also produced a small number of "O.T.O 381/50 1934", which is not much different from the former in design, and the performance is exactly the same.
For this purpose, Ansaldo and O.T.O. produced the first batch of 20 381/50 naval guns, which were planned to be installed on the "Littorio" and "Vittorio Veneto" respectively, and one more was reserved for each battleship. Ansaldo encountered some metallurgical and production problems in the process of manufacturing the gun liners, but they were finally properly resolved. In May 1940, the second batch of 20 naval guns produced for the "Roma" and "Empire" were shipped. As before, spare barrels were reserved for each ship. This batch was named "Ansaldo 381/50 1939" and "O.T.O 381/50 1939" to distinguish them. Apart from this, they were almost the same as the first batch, with only slight differences in details.
Due to the evaluation of the workload, Ansaldo and O.T.O. produced 5 and 15 guns respectively. This means that one of the "Roma" and "Empire" will be equipped with 381/50 guns produced by both suppliers (6 guns made by O.T.O. and 3 guns made by Ansaldo), and the other will be equipped with 9 guns produced by O.T.O. In other words, the 2 spare guns in this batch are produced by Ansaldo. In fact, when the "Roma" was outfitted in 1941, two turrets were O.T.O guns and one was an Ansaldo gun. The "Empire" will be equipped with 9 O.T.O 381/50 1939 naval guns. However, until the Italian armistice on September 8, 1943, the "Empire" did not reach the outfitting stage, even though the gun barrels prepared for this purpose had already left the factory. Soon after its hull was controlled by the German army, it began to be dismantled and metal recycled.
So far, before the end of the war, Italy produced a total of 40 Type 381/50 naval guns, including 4 spare guns. Unfortunately, none of them were preserved, so that the current museum cannot display the original objects to tell this history. On September 9, 1943, the "Roma" sank, and 9 of them sank to the bottom of the sea; in the late 1940s, 18 of them were dismantled along with the "Vittorio Veneto" and the "Italia" (formerly the "Littorio"); the 9 guns on the "Empire" were believed to be seized by the Germans and used as coastal defense guns on a certain coast in Europe. In addition, according to Article 51 of the "Paris Peace Treaty" signed in 1947, Italy was prohibited from owning, producing or using naval guns with a range of more than 30 kilometers (Type 381/50 reached 42 kilometers), and the remaining 4 spare guns were likely to be forced to be scrapped in the 1950s. In addition, there is another piece of evidence that Italy did not keep the gun after the war: in the late 1960s, when the Standing Committee of War Materials in La Spezia needed to conduct a special study on high-speed projectiles (HVP), it had to buy a 381 mm naval gun (actually a 380/45 model) from the "Richelieu" being dismantled in La Spezia. The price was equal to the same quality of scrap metal. This gun is still preserved in the La Spezia arsenal today.
The barrel of the 381/50 naval gun consists of 4 special tubular components, which are heated and hot-pressed according to specific dimensions. The liner with right-hand rifling is about 19.05 meters long and weighs about 19 tons. It is cold-installed and removable, and finally fixed with a lock key. Due to the extremely high temperature and pressure generated during the firing process, the gunpowder chamber (or the ignition chamber of 456.22 cubic decimeters) will gradually erode the rifling as the shells are fired, eventually causing a significant decline in the ballistic performance of the "Vittorio Veneto" class battleships.
After about 140 rounds of firing (some sources say 110 to 130 rounds), the liner needs to be replaced. Compared with battleships of other navies, the barrel life of the "Vittorio Veneto" class is extremely short. For example, the barrel life of the French 380/45 is 200 rounds, the German 380/47 is 240 rounds, and the British 381/42 and 356/45 can even reach 335 and 375 rounds. The muzzle velocity of all the above types of large-caliber naval guns is not as good as that of the Italian 381/50, but the corresponding barrel liner pressure is much smaller.
The breech at the rear of the barrel is made of cast steel, and is connected and fixed by horizontal bolts to the spacer screw bolt (Weling bolt), the firing mechanism, four recoil devices arranged symmetrically along the longitudinal axis of the barrel (pushing the barrel back to the ready position), and a system for exhausting shooting exhaust gas from the gunpowder chamber and the barrel. The barrel and the breech together constitute the "recoil part" of the gun, while the "cradle" is a solid tubular unit made of cast steel and forged steel. When the barrel recoils, it supports the barrel and the slide and slides on the trunnion support shafts on both sides. Below it are the brackets and fixed positions of the recoil device and the inert gas tank, and the structure above is called the "skirt". The cradle and recoil constitute the "elevation part" weighing 102.4 tons, which is fixed parallel to the gun platform by 6 large vertical trunnions, and the flexible support above supports the 3 pairs of trunnions of the 3 barrels. Therefore, the elevation part of all parts is completely independent of other parts, and the barrel can only rely on the rotation of the turret itself when it needs to move horizontally.
The turret itself is basically composed of an armored gun room or a gun turret. According to the structure, it forms a shooting room, an operation room, and a shell changing room. The lower part of the turret structure is connected to the lower hull through a central support shaft through a ball bearing, through which the cables for powering the pitch and slew motors and the fire control command equipment pass. The entire turret rotates on a solid ball platform, which is supported by a cylindrical base closely connected to the hull structure. The armored cylinder (surrounding) around the turret well protects the part below the gun room, which extends down to the main armored deck layer. The joint between the side of the armored gun room and the turret well where the shooting room is located is protected by two half-moon-shaped horizontal armor plates, the thickness of which is the same as the armor on the front top of the gun room.
The rear of the armored turret uses a transverse partition to separate a space for the 12-meter baseline optical rangefinder. The protruding optical instrument parts on the left and right sides are armored and have independent fire control panels. The firing room is divided into three compartments by two longitudinal partitions, each compartment is equipped with a gun. These three compartments can be connected to each other through reasonably arranged openings; the maximum elevation angle of the extended gun barrel is -5° and 36°. In order to protect the connection between the gun barrel and the turret from the influence of weather and sea water, the gun port has a waterproof cover made of artificial leather (i.e., muzzle cloth), which is supported by a light bullet "pants" or a metal frame, which the Italians call "hats" or "underpants". In addition, a distance of about 1 meter is reserved behind the breech of each gun barrel to facilitate the barrel to retreat and return at the maximum elevation. The gun ear journal can slide so that the breech can be opened from the side at an elevation of 15°.
The upper electric shell hoist is installed at the rear and lower parts of the three compartments of the gun room. After the shells and their powder bags pass through the changing room, they are transported to the position of the guns through this ammunition hoist. The loading of each gun is completely independent of other guns, and ammunition is loaded through a folding ammunition rack and a ammunition pusher at a fixed elevation of 15°. The ammunition pusher needs to work three times in a row with different strokes to complete the entire loading action, first pushing the shells, and then pushing the powder bags in two times (the "type one charge" usually used in combat is 3+3 powder bags). Even in the special case of damage to the main ammunition pusher, it can still be relatively slow. When the primer is fixed in the bolt and the breech is closed, the gun to be fired can be adjusted to the required elevation. Under the condition of average elevation (about 15°), the rate of fire of the main gun can reach 1.3 rounds per minute for a well-trained main gun crew, that is, the rate of fire of each gun is 45 seconds per round. All large-caliber naval guns are prone to failure during loading and firing, and the 381/50 type is no exception. The most common failure is the inability to ignite the charge, which is almost always caused by a failure of the primer or electrical ignition. At this time, the shell is still in the barrel and cannot be removed by the ship’s equipment. For safety reasons, a new primer is usually replaced and the charge is tried again instead of opening the breech. In fact, reopening the breech will allow air and oxygen to enter the gunpowder chamber, causing ignition delays and possibly catastrophic consequences (bursts). The explosion will engulf the personnel inside the turret and detonate the charge in the ammunition rack and the ammunition hoist, all the way to the ammunition depot at the bottom. To avoid this extreme situation, some sturdy explosion-proof doors are arranged on the charging path, but these explosion-proof doors are likely to be useless under extremely high temperature and pressure, and will eventually lead to the explosion of the ammunition depot and the sinking of the ship.
The rotation of the turret and the elevation of the gun barrel can be controlled by a worm gear motor with a reducer at a speed of 6° per second. The aiming of the naval gun can be done by manually aligning the aiming point with the quadrant adjusted to the appropriate position according to the data transmitted by the fire control command center, or directly using the optical sight below the rangefinder and on the turret itself (the left one is used to adjust the elevation angle, and the right one is used to adjust the swivel angle).
There are two upper and lower shell hoists inside the turret, which rotate with the turret itself. The lower shell hoist is parallel to the axis of the turret and can "catch" the ammunition in the two circular turntables. The lower layer is used to place shells, and the upper layer is used to place medicine bags. The two electric turntables are installed in two independent compartments, which are connected to the ammunition depot and separated by fire doors. The shells and medicine bags are loaded into the two turntables through hanging rails and slide rails. The ammunition is sent to the bucket of the lower shell hoist through the turntable, and then transported to the changing room by the lower elevator. Here, the shell pusher pushes the ammunition into the upper shell hoist, and the upper shell hoist passes through the watertight well to lift the ammunition to the gun room. In the gun room, the shell hoist aims at the breech of the gun to load the shells, and then moves twice to load the powder bags that match the shells. The spare shell hoist can also complete this series of complex operations, that is, after the powder is loaded at the lower charging turntable, it is directly lifted to the gun room. Although it is extremely slow, it is ready for emergency use. In addition, the "rotating mass" of the entire triple-mounted 381/50 turret is 1591.4 tons (some say 1514 tons), which is roughly equivalent to the displacement of a destroyer at that time.
The design muzzle velocity of the 381/50 naval gun is 870 meters per second. After adjusting the charge, the muzzle velocity of the standard armor-piercing projectile (called "projectile" by the Italian Navy, with a single weight of 885 kilograms) is reduced to 850 meters per second in order to reduce the ablation of the barrel. More importantly, reducing the muzzle velocity can achieve a better dispersion of the projectile when shooting at long distances. At this time, the armor-piercing projectile is loaded with two solvent-free propellants, NAC and FC4. After exiting the barrel at an initial velocity of 850 meters per second, the chamber pressure is 3800 kilograms per square centimeter, and the pressure at the muzzle is 700 kilograms per square centimeter. If the barrel is at the maximum elevation angle of 36 degrees at this time, the range of the projectile will cover 42,800 meters. In more extreme cases, the lighter semi-armor-piercing projectile (824 kilograms) is used to exit the barrel at an initial velocity of 870 meters per second, and its range will reach an outrageous 44,640 meters. Although these data are completely unsuitable for wartime, they can still reflect the actual ballistic trajectory.
The "firing table" of the 381/50 naval gun (a gun performance table based on range tests and supplemented by mathematical calculations) shows that when this type of naval gun fires at an elevation angle of 9°22’ or 166.3 degrees (an angle measurement unit commonly used by artillery, 1 mil = 360°16400 = 0.05625° or 1° = 17.778 mils), the average range is 18,500 meters and the flight time of the shell is 26.35 seconds. At this time, the natural phenomenon of "linear offset" will occur (the lateral offset caused by the rotation of the projectile during flight, which can actually be measured), and the actual impact point will shift 129 meters to the right, and the shell flight trajectory will shift 7.05 mils. The residual speed of the shell after the flight is 588 meters/second, and the landing angle is 11°53’. The firing table shows that on the same plane, for every 1 mil increase or decrease in the gun elevation angle, the corresponding theoretical range will increase or decrease by 83.4 meters.
Unfortunately, there is currently no complete data on the "dispersion" and "average impact point" of the 381/50 naval gun. Unstable gun dispersion is a very normal phenomenon, which will be affected by many different factors: small changes in the gun’s initial velocity; delays in transmitting gun movement to the firing quadrant; minor errors by the firing quadrant operator, etc. Its characteristic is that the variation is large and increases with the increase of distance. The "1940-1941 Gunnery Training Report" mentioned the relevant data measured by the fire control officers at the time (which they considered acceptable): When firing at medium distances (18,000~20,000 meters), the half-must-hit limit of each round of main gun salvos is usually around 200 meters. As the target distance increases, the dispersion will gradually increase rapidly (for example, when the target distance reaches 22,000-24,000 meters, the dispersion value reaches nearly 400 meters), so that there is basically no shooting effect at the maximum range.
This phenomenon was incorrectly attributed to the problem of "barrel heating", which will cause a significant deviation in the gun range during the first shot, but will disappear after several shots. The dispersion problem is a common problem for large-caliber guns in the navies of various countries, but the degree of the problem varies for different types of guns. Except for the special cases of several British and French battleships (which will be discussed in detail in the next article) with completely abnormal gun dispersion, the dispersion value recorded by the 381/50 naval gun of the "Vittorio Veneto" class within a range of 20,000 meters is completely up to the large-caliber guns of the navies of major countries at that time. The average level of naval guns is lower than the 320/44 naval guns of the rebuilt "Giulio Caesar" and "Duilio" classes. Regarding the armor penetration capability of the 381/50 naval gun, its shells can penetrate 348 mm of armor plate at a distance of 23,774 meters when fired vertically (the residual velocity of the shell is 550 m/s); when the firing angle is 50°, the penetration capability drops to 238 mm; the maximum penetration capability is 416 mm at a distance of 19,000 meters when fired vertically, and at a distance of 26,000 meters with a firing angle of 19.3°, its armor penetration is 1.36 mm. The ability is reduced to 124 mm. Since the trajectory of the 381/50 naval gun is relatively flat when firing at close range, and the firing angle of the shell is relatively small, the ability of the shell to penetrate horizontal armor at a distance of 19,000 meters is only 67 mm.
In short, the ballistic performance of the 381/50 naval gun is very commendable. In certain specific conditions, it is better than the naval guns of similar calibers in other countries at the same time, especially when the range exceeds 25,000 meters, almost all naval guns will have obvious dispersion and expansion in direct proportion to the range. In fact, the "Artillery Use Instructions and Specifications" issued by the Italian Navy in September 1942 mentioned that the actual combat range of the 381/50 naval gun is between 19,000 and 21,000 meters. The range allowed for firing is 28,000 to 30,000 meters under excellent visibility conditions, and it is usually reduced to 25,000 meters.
The process of calibrating the 381/50 gun was long and arduous. During the war, the gun mount and auxiliary equipment of this type of gun underwent several modifications. While improving its own reliability, the performance and accuracy of the gun also improved significantly. It can be said to be the pinnacle of naval guns that have been officially in service in the history of the Italian Navy until the decline of the Italian Royal Navy.
152/55 triple gun
The reason why the Navy chose the 152/55 gun as the secondary gun (or anti-torpedo gun) of the "Vittorio Veneto" class battleship is that during the design stage of the battleship, this type of 152 mm gun was the most advanced and immediately available. The 152/55 type was developed from the 152/53 type produced by O.T.O and Ansaldo in the 1920s. It was previously equipped on some light cruisers between 1928 and 1936 in the form of a single-cradle double-mounted turret. After that, Ansaldo developed twin and triple 152mm naval guns with independent cradles for each gun, which were installed on the last two "Captain of Mercenaries" class light cruisers of the Navy (namely the "Duke of Abruzzi" and the "Giuseppe Garibaldi", light cruisers with a full load displacement of more than 11,000 tons), with greatly improved performance. The 152/55 type gun barrel led by Ansaldo in 1934 is longer and has higher thermodynamic performance of the naval gun; in addition, this type of naval gun is designed for new cruisers whose weight problem is not as urgent as that of early cruisers, so it can be improved freely, so the accuracy of the 152/55 type gun is better than that of the 152/53 type. To expand on this, in pursuit of accuracy, compared to the 1000 m/s muzzle velocity of the 152/53 type, the 152/55 type reduces the muzzle velocity to 850 m/s by reducing the charge (the designed muzzle velocity is 925 m/s), the maximum chamber pressure is 3700 kg/cm2, and the maximum range when loaded with armor-piercing shells (49.6 kg) is 25700 meters, while the 152/53 type is 22600 meters. At this time, the charge is 16.4 kg of NAC propellant.
Like the 381/50 type, the 152/55 type naval gun carried by the "Vittorio Veneto" class has two models produced by Ansaldo and O.T.O. The difference is that the Ansaldo gun is a single-tube structure, and the O.T.O gun consists of two hot-pressed pipes. The liners of both can be disassembled when cooled, and the bolts are also longitudinal sliding wedges.
The 152/55 type uses semi-fixed ammunition. Through the "swing arm", it can be mechanically loaded at any elevation angle below 20° (if shooting at a higher elevation angle, it must be reset to 20° when loading). After the shell is aimed at the barrel, it is pushed into the barrel by the telescopic hydraulic feed roller. The maximum elevation angle of the barrel is -5° and 45°. The independent cradle of each gun can be controlled manually, making the entire system highly reliable. The theoretical rate of fire is 4.5 rounds per minute, that is, the rate of fire for each gun is 14 seconds. Excluding the bolt, the "elevation part weight" of a single-seat 152/55 naval gun is 8.85 tons, and the "rotating part weight" including armor is a total of 155.6 tons.
On the Vittorio Veneto class battleships, the turret structure of the 152/55 secondary guns is almost the same as the main turret structure, but the size is smaller and the armored perimeter structure is shorter. In addition to the gun room, the rotating part of the turret also includes the shooting room and the changing room; when loading, the lower shell hoist first lifts the shells from the ammunition depot to the changing room, and then pushes the shells into the bucket of the loading shell hoist through the inclined slide rail. A cylindrical slide is provided at the lower rear of the elevation part of each gun to eject the discarded brass cartridges from the gun hole at the front of the turret.
In terms of armor penetration, the 152/55 shells can vertically penetrate 86 mm of hardened steel armor at a distance of 14,000 meters, but at a 50° firing angle and a distance of 18,000 meters, the penetration capacity is less than 40 mm. For horizontal armor, according to the conventional ballistic curve, the penetration capacity is 43 mm at 20,000 meters and only 18 mm at 14,000 meters. However, as a secondary gun, the 152/55 is mainly loaded with 44.57 kg high-explosive shells to deal with torpedo ships that lack armor. Like the 381/50, the "Gunnage Use Instructions and Specifications" also specify the combat range of the 152/55 gun when it is carried on a battleship. According to different shooting targets, there are two options: (a) Cruisers, with an average combat distance of 15,000 to 17,000 meters, using armor-piercing shells; (b) Torpedo ships, with an average combat distance of 12,000 to 14,000 meters, using high-explosive shells. The firing distance under normal visibility conditions is within 16,000 meters, and it is increased to 20,000 meters when visibility is excellent. In the case of a battle with a cruiser, the distance values are 18,000 meters and 20,000 meters respectively. When firing high-explosive shells at a distance of 17,500 meters, the average dispersion of the salvo is inferior to that of the early Italian 152mm naval guns. The dispersion value is usually 160~200 meters, which is quite large for medium-caliber naval guns, but fortunately it is within the controllable range; the dispersion will increase with the increase of range, while the dispersion value of armor-piercing shells (49.5 kg) loaded at the same distance is 80-90 meters, which is completely acceptable. The reason for the huge difference is basically attributed to the fuze problem of the Italian 152mm high-explosive shells, and the problem obviously exists in the flight stage of the shells rather than the firing stage. In 1941, naval personnel were aware of this problem and tried to solve it from the two aspects of the external shell shape and internal weight distribution. In short, the "Vittorio Veneto" class battleships and the "Garibaldi" class cruisers proved that the 152/55 naval guns and their systems are indeed powerful and accurate enough.
Since the mid-1930s, the Italian Navy has begun to develop ship-borne anti-aircraft artillery to replace the 100/47 twin-mounted guns commonly carried by large ships at the time. The 100/47 twin-mounted gun originated from the former Austro-Hungarian Skoda K10 100mm gun. In the 1920s, O.T.O copied the 100/47 1924 model, and its subsequent models were almost carried on all cruisers of the Italian Navy and the rebuilt "Cavour" class battleships. This type of artillery is recognized as having both firepower and accuracy, and excellent ballistic performance. The anti-aircraft model is installed on a special and sophisticated twin-mounted gun mount. It adopts a single cradle structure and is equipped with a trunnion that can adjust the height. The elevation is achieved by manually operating the trunnion, and the maximum elevation angle of the elevation mechanism is 85°. However, as time went on, its slower speed, especially the pitch speed, could no longer meet the needs of fighting against high-speed aircraft, because tracking and aiming at such targets required very rapid adjustment of the aiming line. The Navy began to evaluate anti-aircraft guns with a caliber between 66 and 127 mm. In addition, large-caliber anti-aircraft guns themselves had technical bottlenecks. Finally, the Italian Navy chose a compromise between firepower, weight and rate of fire, namely the 90/48 anti-aircraft gun presented by Ansaldo, which was later developed into a 50-caliber gun and was installed on ships over 5,000 tons starting in 1938.
As mentioned in the previous article, the 90/50 guns will form the main anti-aircraft firepower of the "Vittorio Veneto" class battleships. They are regularly arranged between the No. 2 and No. 3 turrets along the central axis of the hull, with 6 guns on each side. In order to ensure a good firing range for each gun, the layout at the beginning of the design was in the shape of an inverted bow, that is, the two guns in the center were separated from the side of the ship. Later, it was modified to a positive arc, and the layout was more straight and tight. The 90/50 type is a flexible single-mounted gun. The 1050 kg barrel is connected to the breech to form a special "bayonet" system for quick replacement. The breech structure consisting of a longitudinal sliding wedge bolt, a recoil brake (above) and a double recoil mechanism (below) is attached to a tubular cradle, with a maximum recoil distance of 530 mm and a pair of gun ears. The gun carriage structure is relatively unique, with a central support shaft placed in front of the breech. In order to reduce the height of the trunnion from the loading platform at high elevation angles, the trunnion is installed as far back as possible; at the same time, in order to balance the weight of the elevation part, the weight of the breech block has been significantly increased.
The subsequent 90/53 anti-aircraft gun is still jointly developed and produced by Ansaldo and O.T.O. Although the suppliers are different, the main technical characteristics and performance are almost the same: the muzzle velocity is 845~860 meters/second, the maximum chamber pressure is 3570 kilograms/square centimeter, the pressure at the muzzle is 730 kilograms/square centimeter, and the maximum horizontal and firing heights are 15548 meters and 9000 meters (estimated). In order to reduce the wear rate of the liner, the muzzle velocity is slightly reduced, but it can still ensure the average stability of the flight speed of the projectile.
90/50 uses fixed ammunition with a charge of 18.41 kilograms, including 10 kilograms of projectiles (high-explosive anti-aircraft shells). Well-trained operators can increase the 90/50’s rate of fire to 16 rounds per minute, but in actual combat conditions the rate of fire will drop to 12 rounds per minute, or one round every five seconds. The ammunition is supplied directly to the ammunition depot by a conveyor chain, and is manually loaded at any elevation angle with the aid of a hoisting tray and a feed roller. After the ammunition arrives at the loading platform, the ammunition fuse is adjusted according to the instructions of the fire control center. In some cases, flares can also be loaded, but after all, they are relatively small in caliber and can only provide limited illumination. In order to save costs, lower-quality steel was used in the production of the 90/50 armored piers, which also relatively saved production time. The ingenuity of its shipborne structure lies in the fact that the turret base is equipped with a stabilizer to offset the roll and pitch of the ship during normal navigation, thereby reducing the adverse effects on the accuracy of the shells at high elevation angles. The turret itself is an elliptical, fully enclosed type, which shields the muzzle storm when the three main guns fire at a large swing angle.
The entire turret (including the gun shield and loading platform) is loaded in a buttress about 2 meters above the deck. The turret weighing 19,072 kg can now use the gyroscope system and electric auxiliary equipment in the tower to instruct two motors and gear transmission machines to perform a 16° reaction shake around the turret center axis to offset the vibration caused by severe sea conditions or when the main turret is firing, that is, the entire turret system is as stable as possible in the horizontal and vertical axes. The turret buttress and the center axis are directly arranged on the deck and do not penetrate the deck, thus ensuring the integrity of the turret structure and avoiding the impact on the hull armor structure; because the opening of the upper deck is not large, it is more convenient to replace the entire air defense system during the service life of the ship if necessary.
In March 1938, after the ballistic characteristics of the 90mm gun were improved, the Navy installed two 90/48 anti-aircraft guns on the cruiser "San Giorgio", which had become a training ship at the time, to test the complete stabilization system. They were located on the top of the 190/45 naval gun on the starboard side of the "San Giorgio", which was approximately the same height as that later installed on the "Vittorio Veneto" class battleship. The test was carried out in La Spezia. In order to simulate the shaking of large ships during navigation, the Navy also had a test system on the "San Giorgio", which was designed to fill and transfer a large volume of liquid in a short time to cause the hull to shake. The test results were gratifying. Later, the slightly improved 90/50 type was not only installed on the new battleship, but also the rebuilt "Andrea Doria" and "Duilio" were also equipped with 10 such guns each.
The performance and accuracy of the 90/50 gun are beyond doubt, but as a ship-borne anti-aircraft gun, its anti-aircraft capability may be slightly compromised due to the characteristics of anti-aircraft shells. However, the land-based version of this type of gun, the 53-caliber 90/53 gun, was one of the best guns in Italy during the war, even better than the 88mm gun of the German army next door, and served until many years after the end of World War II.
From the actual service performance, the 90/50 anti-aircraft gun itself is much better than the gun mount, because the stabilization system of the gun mount has defects in the electrical and electromechanical systems. When the 90/50 was equipped, the navy found that the gap between the armored buttress and the turret was not waterproof enough, and rain and waves would penetrate into the turret and damage the motor. Later, someone tried to use waterproof cloth to solve this problem, but it never solved the root cause. In addition, the stabilization system itself is very fragile, and motor damage occurs from time to time; this situation is more serious on the "Doria" class battleships with lower freeboard. Unfortunately, Italy’s electromechanical production level at that time was completely unable to keep up with the innovative stabilization system of the 90/50 type, not to mention that a single turret weighed 20 tons. Therefore, single or several 90/50 type guns on the "Vittorio Veneto" class battleships often malfunctioned, causing the system’s functions to be limited to anti-aircraft barrage shooting and conventional anti-ship. The "Doria" class battleships directly disabled the 90/50 type stabilization system
120/40 type single-mounted gun
The early 120mm guns were widely used on various old destroyers and cruisers of the Italian Navy. By the late 1930s, the navy believed that its horizontal range was insufficient (6400 meters) and gradually abandoned it. In the spring of 1940, on the eve of the official commissioning of the "Vittorio Veneto" class battleships, the Navy decided to recycle some Armstrong 1891-1899 120mm guns from some retired old armored cruisers and carry four guns on each of the "Littorio" and "Vittorio Veneto". The guns did not contain any form of electrical auxiliary equipment, and were simply bolted to the deck for lighting purposes and equipped with a small steel gun shield. Two doors are installed on each side of the No. 4 90/50 anti-aircraft gun located in the middle of the ship. For this purpose, a small platform is extended outward on the deck to facilitate the gunner to move around the gun. The muzzle velocity of the 1891-1899 120 mm gun is 654 meters per second, and the shell weighs 19.76 kilograms. Theoretically, the range is 9,500 meters at the maximum elevation angle of 32 degrees. In fact, this range is far from enough. Due to the characteristics of the flare, the shell must be detonated at least 500 meters above the target and continue to illuminate the target outline for 25 to 30 seconds.
This type of artillery uses semi-fixed manual charging. Each shell weighs 29.30 kilograms, and the brass cartridge containing propellant weighs 9.54 kilograms. The rate of fire is 6 rounds per minute, that is, 1 round every 10 seconds. There is also a short cartridge weighing 4.76 kilograms, which can be used as a salute. The gun weighs 2.08 tons, the gun carriage including the cradle and platform weighs 3.8 tons, and the entire gun system weighs 5.92 tons. During the exercise of the "Vittorio Veneto" class battleship, it was found that these 120/40 guns could only effectively illuminate targets within 5,000 meters. In 1941, a naval commander believed that this type of gun was completely insufficient and the loading speed was particularly slow, so he urged the navy to replace these old 120/40 guns as soon as possible.
However, similar guns still exist on the second batch of "Roma" ships in service, indicating that the navy does not seem to have found a better alternative. In fact, the navy has started the research and development of new 120mm and 135mm lighting guns since 1940, but it ended in vain.
Automatic weapons
The Breda 37/54 and 20/65 light machine guns have a good balance of range and accuracy. Although they are limited by the automatic system (the principle is to use the gunpowder gas of the barrel to push the bolt back, extract the shell and load the next shell), the rate of fire is still 140-150 rounds/minute. Because the twin rigid gun mount is extremely heavy: it needs fixed structural support, the vibration generated during shooting often affects accuracy. The four single 37/54 machine guns on the bow of each Vittorio Veneto class ship are significantly better than the twin version because they can drive the recoil gun mount of the barrel.
The number of Type 37/54 guns carried on all Vittorio Veneto class battleships is the same, while the number of Type 20/65 guns carried has been increasing, which we will discuss next.
Type 37/54 single/twin machine guns
There have always been two versions of Type 37/54 guns on the Vittorio Veneto class battleships, the twin Breda 1938 and the single Breda 1939. The 1938 model was developed from the earlier 1932 model. The biggest difference is the barrel cooling system. The 1938 model uses air cooling instead of the liquid cooling of the 1932 model; this is a gas-operated automatic weapon with a fixed barrel and recoil completed by the breech mechanism. The ammunition feeder is a 6-round plate. Both types of machine guns on the ship use plate feeding. Theoretically, by continuously inserting the bullet plate, the firing rate can reach 200 rounds per minute, but in long-term shooting, loading will inevitably be delayed, so the actual firing rate is about 140 rounds per minute. The muzzle velocity is 800 meters per second, and the ammunition curve is quite flat; the maximum horizontal range is 7,800 meters, the firing height is 5,000 meters, and the effective firing height is about 4,000 meters. The total length of the ammunition is 384 mm, of which the brass cartridge is 251 mm long, and the ammunition with tracer and time fuse is 162.5 mm long and weighs 1.6 kg.
The twin-mounted type is a rigid gun mount, and the magazine is loaded from the top of the machine gun. The overall weight of the machine gun is 4,300 kg, of which the two gun barrels weigh 554 kg, and the remaining 3,746 kg is the weight of the gun mount. It is a platform-type gun mount with an axis length of 1.25 meters and a maximum elevation angle of -10° and 80°. The operators of the Type 37/54 machine gun consist of 7 people (gunner, elevation operator, rotation operator, two loaders and two ammunition carriers). The ammunition is taken out from the nearest medicine cabinet and loaded. When shooting, tracking and aiming can be carried out through the gun’s own sight or the data of the fire control computer. The 1938 model also specially installed a simple stabilization device weighing 700 kilograms, which is designed to offset the tilt of the platform itself. A roller system is inserted between the base of the turret and the gun mount, relying on gravity to make the turret swing up to 10°, but it did not achieve the expected effect in actual operation and was discontinued soon after.
The Breda twin-mounted 37/54 The 1938 machine gun has obvious shortcomings. The two gun barrels are fixed on the entire machine gun, that is, the rigid gun mount is too heavy, resulting in horizontal stress and pressure reaching 23 tons and 27.2 tons respectively, close to a single 100/47 gun. Therefore, a heavier structural support is required, and the accuracy is affected by vibration during shooting. At the beginning of the design of the new battleship, it was planned to carry 6 37/54 twin-mounted machine guns, 3 on each side of the front smoke. On June 4, 1937, the ship project committee finally determined that there would be 8 guns, 2 on the top of the No. 1 and No. 3 turrets, and the 2 guns in the midship part were replaced with 20 mm guns. At the same time, the Navy asked Breda to develop and install the 37/54 type machine gun, which was planned to be placed on the centerline of the hull in front of the No. 1 turret for air defense in the bow area. At the same time, considering the special position of the bow, which is easily affected by the muzzle storm of the main gun, the Navy decided to install it on a gun mount that can be easily stored under the forecastle deck. The single-mounted 37/54 1939 model was born, and later proved to have excellent performance and can serve for a long time. This model is air-cooled, and the gun is turned 90° on the gun mount to change to horizontal feeding, abandoning the previous vertical feeding mode. The gun mount itself is installed on a movable base. At the maximum elevation angle of 90°, the entire gun can be vertically lowered into the cylindrical cabin under the forecastle deck through the watertight hatch. In order to reduce the stress on the base during shooting (since the base needs to move along the vertical rail, it is neither strong nor heavy), the gun mount is not directly connected to the gun like the twin-mounted model, but adopts an improved recoil system (the maximum recoil distance after braking is 100 mm), and the ear shaft, brake cylinder and elevation mechanism are all installed on the gun mount. The total weight of the entire single-mounted 37/54 system is 1,500 kg, of which the gun weighs 380 kg. The horizontal stress and pressure have been reduced to 3.46 tons and 5.13 tons respectively. Compared with the twin-mounted type, the vibration generated during shooting is significantly reduced, and the accuracy is also effectively improved.
The three "Vittorio Veneto" class battleships that were officially commissioned were equipped with 20 37/54 machine guns, including 8 twin-mounted and 4 single-mounted. This number did not change during the war. In September 1943, the "Vittorio Veneto" removed a single 37/54 machine gun on the bow during a short-term repair in La Spezia, and the gun was never reinstalled.
20/65 twin-mounted machine gun
The "Vittorio Veneto" class battleships only carried one type of 20 mm gun, the Breda 20/65 1935 model. This type of machine gun originated from the Breda 1931 13.2 mm machine gun, which was a copy of the French Hotchkiss machine gun of the same caliber. The Breda 1935 20/65 gun is a gas-operated, air-cooled automatic weapon with a regulating valve. The barrel is fixed and the recoil is completed by the breech mechanism. The gun weighs 72 kg, the muzzle velocity is 825 m/s, the maximum horizontal range is 6100 meters, the maximum firing height and the actual firing height are 2900 meters and 2500 meters. The theoretical cyclic rate of fire is 240 rounds per minute, and the actual rate of fire is 150 rounds per minute. The brass or steel shell is fixed with 38 grams of smokeless or EC4 powder, and the ammunition weighs 0.134 kg. The cartridge weighs 320 grams) The magazine loaded with 12 shells weighs 5.6 kg, of which the magazine weight is 1.76 kg. As shown in the schematic diagram, the twin 20/65 cannon is mounted on a rigid gun mount, equipped with a unique counterweighted cradle, and the guns (one is fed from the right hand side and the other is fed from the left hand side) are arranged in a stepped manner on the cradle. This cannon can be operated by one person and is equipped with a simple stabilization system similar to the twin gun mount of the Breda 37/54 cannon mentioned above, and its performance is slightly better than the latter; however, it seems to have been discontinued later, with a maximum elevation angle of -10° and 100°.
The entire gun installation weighs 2,330 kilograms, which can be said to be very bulky; most importantly, it brings severe vibration to the base structure (horizontal stress and pressure are 11.5 tons and 12.3 tons respectively), just like the 37/54 cannon, which greatly affects the accuracy of the gun. Despite this, the close-range anti-aircraft performance of the 20/65 machine gun is still strong, so it is widely carried on various ships of the Italian Navy. The Italian Army also widely uses this type of machine gun to play an anti-tank and anti-aircraft role.
Initially, the "Vittorio Veneto" class was planned to carry 6 twin 20/65 machine guns. When the first batch of new battleships entered service, the number increased to 8, of which 6 were installed on platforms consistent with the 37/45 type on both sides of the hull, and the remaining 2 were located slightly behind the 90/50 type gun. In order to strengthen the anti-aircraft capability of the stern area, starting in 1938, the Navy decided to add a 20/65 machine gun on each side of the No. 3 turret, and at the same time required the gun mount to be retractable to avoid the impact of the 152 mm gun muzzle storm. The result of this plan is unknown, but in fact, by 1941, only two 20/65 machine guns that were exactly the same as before were added to the above position. So far, the number of 20mm guns on each "Vittorio Veneto" class has reached a total of 20 barrels.
The navy’s pace has not stopped. In the first half of 1942, in order to further strengthen the close-range air defense capabilities of the bow and stern, "Littorio" added another 4 20/65 type, 2 located on the top of the front 152mm turret, 2 located on the rear deck, a total of 14 20/65 type machine guns; "Vittorio Veneto" and "Roma" added to 16, compared to "Littorio", there are 2 more, located on a small platform close to the second turret buttress
In addition to all the above-mentioned shipborne guns, the "Vittorio Veneto" class battleships, like other ships of the Navy, also carry some small infantry support weapons, with corresponding ammunition and operators, and on large ships there will be "landing troops". As for the "Vittorio Veneto" class battleships, each ship will be equipped with one or two Breda 1931 model 13.2 mm heavy machine guns; 8 Breda 1937 model 8 mm machine guns: with standard army triangular gun mounts, which can also be installed on simple rotating gun mounts to defend against enemy raids when the ship is anchored; 10~12 Breda 1930 model 6.5 mm light machine guns; 360 Type 91 6.5 mm carbines with standard bayonets (a total of about 135,000 rounds of ammunition); 100~150 Beretta 1915/19 model 7.65 mm semi-automatic pistols (a total of about 19,800 rounds of ammunition), and more than 2,000 various grenades.
Fire control system
When the war came, in order to maximize the combat efficiency of all shipborne weapons on the "Vittorio Veneto" class battleship, the Italian Navy equipped it with the most advanced shipborne fire control equipment in the country in the late 1930s. In particular, the technical level of the large-caliber and medium-caliber guns on the ship is consistent with that of the navies of other powers, but all fire control systems have limited capabilities when facing harsh sea conditions and ships in sail, which we will discuss below. For anti-aircraft guns, 90mm anti-aircraft guns are theoretically capable of air defense combat missions, while the centralized fire control systems of 37mm and 20mm machine guns are difficult to break through the technical bottleneck. Through the attached figure, we can roughly understand the firing process of large-caliber naval guns, which is also applicable to medium-caliber naval guns.
First, after the chief fire control officer designates the target in the main fire control room, he uses the optical sighting system to determine the relative azimuth between the bow direction and the target. At the same time, the rangefinder provides the distance to the target, and then the inclinometer behind the rangefinder provides the value of angle B (that is, the angle between the turret swing angle and the target heading). The corresponding swing angle is automatically transmitted to the ship’s gun, which immediately points to the target, and the distance and angle B are transmitted to the fire control center. This system consists of multiple components and is capable of simultaneously measuring the heading and speed values of the target ship, as well as the current wind speed and direction (which has a significant impact on the trajectory of the artillery shells, especially when the target distance increases). Based on the above continuously updated information, the fire control center begins to determine the "future point" of the target (the fire control center is basically an electromechanical computer with a preset firing table in its "memory"), calculates the appropriate pitch angle and aiming point, and transmits it to the ship’s gun. To hit the target, the fire control center needs to make accurate calculations, and the vertical stabilization system (composed of a group of gyroscopes mounted on a universal joint, also known as a "vertical gyroscope") is required to record the changes in the ship’s longitudinal tilt, and transmit the pitch angle and gyration angle to be adjusted to the naval gun; the naval gun then continuously makes necessary adjustments in the vertical and horizontal planes through the fire control quadrant. When the chief fire control officer thinks everything is in place, he will issue a firing order, and then prepare to observe the water column stirred up by the landing point of the shell, and use the acoustic measuring instrument to measure the impact point of the salvo, calculate the flight time according to the theoretical trajectory of the shell, and then evaluate the azimuth and range errors in the absence of other external interference factors and abnormalities, that is, the error of the "future point" calculated by the fire control center, and then transmit it to the fire control center for recalculation, and finally repeat this step in the next salvo until the gun accurately hits the target, that is, the target position coincides with the average impact point of the salvo. It should be emphasized that the actual operating procedures of the Navy are much more complicated than the above-mentioned operating procedures. The evaluation and decision-making of the fire control officer are very important. Mastering this skill requires sufficient experience, adequate preparation and continuous training.
The basic principle of anti-aircraft firepower shooting is not much different from the above. The biggest difference is that the target will move freely in three dimensions, so the difficulty of anti-aircraft fire control is even higher. In addition, the time reserved for the fire control system to calculate the high-speed moving aircraft is quite short, and the time fuse of the anti-aircraft shells must be set to ensure that the anti-aircraft shells explode in the direction closest to the target aircraft.
Fire control equipment
Let’s not talk about the auxiliary fire control equipment on the "Vittorio Veneto" class. Its main fire control equipment includes: optical rangefinder, inclinometer and optical sighting system and electromechanical computer in the fire control center.
As was the case with the previous production of medium and large caliber naval guns, the Navy allocated the production order for the fire control equipment of the new battleships to two domestic suppliers, namely "San Giorgio" (abbreviated as "SG") in Genoa and "Galileo Factory" (abbreviated as "OG") in Florence, and required them to produce equipment with similar technical characteristics and functions. Therefore, the "Littorio" built by Ansaldo will use the fire control equipment produced by SG. If the outfitting of the "Imperial" can be completed smoothly, its fire control equipment will also be provided by SG; and the two "Vittorio Veneto" and "Roma" produced by C.R.D.A will all be equipped with OG equipment.
In the past few decades, the rangefinders used on Italian warships were mostly imitations of British and German products. At this time, the domestic rangefinder production industry had just started. Around 1928, Italian-made rangefinders began to be installed on Royal Navy ships. Initially, they only produced combined-image rangefinders, and then developed into stereoscopic rangefinders. In addition to gradually improving the imaging quality and measurement accuracy of the rangefinders, they also needed to be equipped with flexible brackets to avoid adverse effects caused by any vibration on the ship, which was crucial for rangefinders installed at high altitudes. By the late 1930s, the production technology of the two suppliers, SG and OG, had become quite mature, with excellent product performance, and even some large-scale rangefinders reached the most advanced level at the time. There were also some technical bottlenecks that could not be broken through in a short period of time, such as how to achieve complete waterproofing of the equipment, effective mechanical systems for cleaning lenses, and most importantly, there was no technology for anti-glare treatment of optical components at the moment, but as the war progressed, these technical bottlenecks were overcome one by one. Some of these problems were solved with technical assistance from Germany, because Germany’s development in the field of optics has always been at the forefront of the world.
A total of 24 rangefinders (26 on the "Littorio") are installed at different locations on the hull of the "Vittorio Veneto" class, of which 20 have baselines greater than or equal to 3 meters. For each 381 mm turret, a 12-meter baseline dual rangefinder (one combined image type and one specific sight type) will be installed at the rear of the turret; a circular 7.2-meter dual rangefinder on the upper level of the rangefinder tower, which can rotate 360°; there is a 7.2-meter stereoscopic rangefinder on the lower level of the tower, which the Navy calls a "tactical rangefinder". It is not usually used for shooting operations, but mainly provides distance readings for officers on the bridge below; there is a 6.3-meter stereoscopic rangefinder at the rear of each of the four 152 mm turrets; there is a medium-caliber naval gun firing director station on each side of the elevated platform of the chimney, equipped with a rotatable 5-meter dual rangefinder system; a total of two 3-meter stereoscopic rangefinders with stabilizers and altimeters are installed in the rangefinder towers on both sides of the turret, used to direct the firing of 90 mm guns; finally, there is a 3-meter stereoscopic rangefinder located on the bottom platform of the main mast. The remaining four 2-meter stereoscopic rangefinders were integrated into the same number of firing directors (operated by five people) for calculating and summarizing firing parameters (providing rotation angle, distance and elevation parameters for 37/54 guns, and only rotation angle and distance parameters for 20/65 guns). Two of them were located on both sides of the ship’s swollen anti-aircraft platform, and one each on the elevated platform on both sides of the front of the rear chimney. There are also two 2-meter stereoscopic rangefinders installed with 3-meter rangefinders in the front of the anti-aircraft firing director station of the "Littorio", which is a sign to distinguish it from its sister ship "Vittorio Veneto".
There are a total of 8 optical sighting equipment (target azimuth acquisition) on the ship, consisting of high-magnification optical instruments installed on a stabilizer, used to acquire targets and measure the rotation angle required for guns when firing (the azimuth of the target also needs to be measured when firing against the air). One main gun optical sighting device is located at the top of the tower, rotating synchronously with the main gun turret and controlled by the chief fire control officer; another main gun optical sighting device is installed in the armored firing director station of the ring rangefinder tower at the lower seventh floor of the tower, also rotating synchronously with the main gun turret and controlled by the deputy fire control officer; two 90mm gun optical sighting devices are installed in the firing director stations on both sides of the command bridge layer at the lower position of the tower and rotate synchronously with it; another two optical sighting devices with stabilization devices are installed in the small superstructure extending from the above-mentioned anti-aircraft director station as a backup. At the same time, the No. 2 and No. 3 main gun turrets (using their own instruments) can also provide optical sighting functions for the main gun and one or two of the four 152mm turrets (port and starboard). Other optical sighting equipment consists of two night rapid response anti-ship firing directors on both sides of the turret officer’s bridge. In order to concentrate anti-aircraft firepower, several small-sized independent directors (single-person operation) are installed around the tower, covering the bow, stern and both sides. The number of independent anti-aircraft directors on the "Roma" has increased significantly.
The inclinometer is a light optical device with a simple electromechanical computer that predicts the inclination of the naval target’s course based on the distance and manually input ship length. Six of them are placed in pairs at the front of the two rangefinder towers, and one each at the two medium-caliber naval gun director stations.
There are a total of 5 fire control centers on the ship, 1 for the main gun, 2 for the medium-caliber guns, and 2 for the 90 mm guns, all located below the gun deck. The main gun fire control center is located on the middle deck below the No. 1 turret. The Navy calls it the "four-type" assembly, which is developed from the "one-type" assembly on the heavy cruiser (203 mm caliber); the basic structure is designed by R.M. (Navy), and SG and OG are responsible for construction. This is a highly automated electromechanical analog computing device, consisting of a large main control console for controlling the computing mechanism and a large number of auxiliary equipment. The latter includes rangefinder distance and B angle estimator; gyroscope and coordinate locator; electrical control panel; gunnery data recorder; turret firing control panel; data receiver that receives data from optical sighting equipment, actual heading and speed, rudder angle, wind speed and direction, temperature and atmospheric pressure, ammunition depot temperature, and data such as gyroscope and pitch angle automatically transmitted to the turret aiming quadrant. Although highly automated, the system still requires a certain amount of manual operation to operate normally, so it needs to be equipped with a large number of professionally trained operators. The accuracy of its on-the-spot calculations is generally excellent and comparable to the equipment of other navies of the same period. Normally, the system takes about a few minutes to obtain target information, but as the target ship’s movement changes, the system’s "response time" will gradually increase due to the delay of the electromechanical system itself.
The "Type 2" fire control system components used for medium-caliber naval guns are located on the left and right sides of the No. 2 turret buttress on the middle deck, and are used for the port and starboard secondary gun groups. This system is similar to the "Type 4" components but is not complicated. It was previously used on light cruisers (152 mm caliber). The fire control system of the 90 mm gun (also called the "anti-aircraft fire control component") is located on both sides of the main gun fire control center between the front 381 mm turret buttresses on the middle deck. In addition to the main fire control system, there are 9 scaled-down components:
Main gun: a "Type 3" secondary fire control component at the rear of each Type 381/50 turret; R.M
Medium caliber gun: a "Type 4" secondary fire control component at the rear of each Type 152/55 turret;
90mm gun: the rapid response computer ("anti-aircraft fire control component") is located in the superstructure on both sides of the turret where the anti-aircraft director is located.
Fire control mechanism
The above equipment allows the "Vittorio Veneto-class battleships to choose various centralized fire control schemes.
I Large-caliber naval guns
(a) All main turrets are commanded by the chief fire control officer in the upper fire control room, who decides to use the fire control component for shooting calculation tasks. In emergency situations, the secondary fire control component of the second or third turret can be used.
(b) All main turrets are commanded by the deputy fire control officer in the armored fire control room, which is equipped with the same equipment as (a).
(c) Turrets No. 1 and No. 2 are commanded by the deputy fire control officer, using the primary fire control component or the secondary fire control component of turret No. 2; the main fire control The officer controls turret 3 and uses the fire control unit in the turret.
(d) All main turrets are commanded by the fire control officer of turret 2, using the primary fire control unit or the secondary fire control unit of turret 2.
There are still cases where turrets control firing independently, that is, turret 2 controls turret 1, turret 3 is independent, or all three turrets are completely independent. In the case of night shooting, usually at short distances and without using fire control units, the directors on both sides of the officer’s bridge can control all main turrets, or only the bow turret or the stern turret.
Ⅱ Middle caliber naval guns
(a) The firing director station with built-in fire control components on both sides of the hull controls the port and starboard turrets (usually used for daytime shooting operations).
(b) The night firing director commands one or two turrets on the left and right sides without using gun components (used for daytime close-range or emergency shooting or night shooting)
(c) Medium-caliber naval guns can also fire independently, or in groups of two using the turret’s own fire control components.
Ⅲ Small-caliber naval guns
(a) The anti-aircraft director stations on both sides of the hull connected to their respective fire control components control the six 90mm turrets on their side (usually used for air defense shooting operations or anti-ship shooting operations during the day). ).
(b) Two anti-aircraft director stations control the 90mm gun batteries on the left and right boats, using their respective fire control components for rapid response calculations of air and anti-ship data. In the absence of fire control components, the 90mm gun batteries are controlled by the director for anti-ship shooting operations (daytime).
The 120/40 guns on both sides of the hull are usually controlled by the night-fire director to fire flares. In some cases, the 90mm gun batteries on the front two sides may assist the 120/40 guns in night-time illumination operations. In the Navy’s preliminary research, it was considered that the two 90mm guns were also used for night illumination.
The 20mm and 37mm guns are directed by directors that can quickly calculate relevant data when firing air. The twin 37mm guns can automatically receive the parameters of the slew angle and elevation angle, and can also aim independently with the help of the plotter installed on the gun mount. The 20mm guns and single 37mm guns can also receive the parameters of slew angle and distance. The Vittorio Veneto class divided the anti-aircraft weapons on board into three groups: the "forward group" consisting of all anti-aircraft guns in front of the bridge, the "swell group" consisting of all 37mm and 20mm guns on the swell anti-aircraft platform, and the "stern group" consisting of the 90mm gun and all the machine guns behind it.
The Italian Navy’s guidance also stipulates that the three 381mm turrets should be divided into three groups, that is, turret No. 1 corresponds to "group 1", and so on. The document does not stipulate broadside salvos, but requires that all turrets must fire in "groups" (at least one group, at most two groups) in order to achieve as many "average salvo impact points" as possible within a given time, which is particularly important during the "effective firing" phase. In combat, the main guns use the "clip method", that is, three rapid salvos are fired in succession at the beginning (when possible, the third group No. 3 turret will fire first), and the elevation angles of all turrets are calculated by the fire control center, but the aiming point increases or decreases by 7 places before and after the target position during the first and third salvos. If there is no serious and unlikely error in the calculation of the "future point", it is very likely that one of the three salvos will land at the center of the previous aiming point. Then, the pitch angle is adjusted according to the impact point of these three salvos (far or near) to correct the corresponding range. The correction range is initially ±800 meters, which is twice the average dispersion value (320/44 type and larger caliber guns), and then reduced to ±400 meters until the main gun hits the target. Next, the "effective shooting" stage is entered, and the main gun fires at the highest possible rate of fire. The "improved shooting" method can also be used during the aiming process. The first round of salvos is carried out according to the shooting parameters provided by the fire control system, and then the pitch angle is adjusted gradually. It is obvious that the shooting operation will become extremely slow, so it will only be used when a single turret is firing independently and the ship rolls more than 5° in high sea conditions.
In the latter case, in addition to overcoming the sway caused by the gun’s own firing and the movement of the ship, the aforementioned guidance document also mentioned: "...test results show that, except for the stabilization device on the 90mm anti-aircraft gun, we do not have equipment that can make sufficiently accurate approximate corrections to the tilt of the gun trunnion, which is enough to affect the shooting accuracy. "Due to the inability to automatically correct errors, the Italian Navy proposed some practical shooting rules that would have an adverse effect on the rate of fire, but did not completely eliminate the errors during shooting. The lack of accurate data on axial offset is one of the important reasons... The first of these principles recommends always firing when the roll reaches the crest of the wave when the ship’s sway exceeds 2 degrees. Next is the guidance on calibrating the aiming point, and finally it is recommended to accept the inevitable axial offset after continuous salvos, especially in high sea conditions, because the offset of the gun trunnion and the degree of sway of the ship can never be constant. At the same time, avoid continuously correcting the gun based on observations.
Medium-caliber naval guns generally adopt the "rapid shooting" mode in combat, tending to "cover the target with rapid firepower, maximize the characteristics of the short flight time and low initial error probability of medium-caliber naval gun shells, and conduct short-range shooting (average range 16,000 meters)". The first round of salvo (port or starboard gun group firing) will use the fire control center to provide elevation and aiming point data, and subsequent salvos will be gradually corrected according to the observation results of the impact point, first correcting the aiming point and then correcting the elevation. It should be noted that when only optical instruments are used, the aiming point must always be in the center position, otherwise it is difficult to estimate whether the range is far or close.
Ammunition and ammunition depot
As mentioned above, the 381/50 naval gun uses split ammunition, that is, the shells and propellants are loaded separately, and the propellants are composed of several medicine bags. The 381/50 naval gun can be loaded with two types of shells. One is an armor-piercing shell, which the Italian Navy calls "projectile". The warhead is made of chrome-nickel steel, weighs 885 kg, has a charge of 10.16 kg, has a base delay fuze, a hard steel cap and a silicon-aluminum alloy wind cap, and is 170 cm long. The other is a semi-armor-piercing shell (SAP), which has similar technical characteristics to the armor-piercing shell, weighs 824 kg, has a charge of 25.91 kg, and has a base delay fuze and a wind cap. During the war, the Navy did not encounter major problems in the use of armor-piercing shells, but the fuse of the semi-armor-piercing shell is usually triggered later. For example, the semi-armor-piercing shell will explode only after excessively penetrating the hull of a light ship.
The firing charge uses NAC type gunpowder (produced by Dynamite Nobel) or FC4 type gunpowder (produced by BPD, Italy), which is packed into a single 44 kg package with waste silk. Each package is mixed with a small amount of sensitive explosives, enough to detonate the entire package. The "type one charge" mentioned above means that the shells are charged in two processes during wartime, and three packages are required for each process. There is also a "type two charge" that is usually used for exercises or coastal bombing. In order to minimize liner ablation, the charge amount depends on the type of shells, ranging from 3 to 4 packages. There is also a "type three charge" dedicated to training. The Navy has designed and tested a high-explosive shell (weighing 774 kg) for the 381/50 gun, but it does not seem to have been equipped on the "Vittorio Veneto" class battleships.
The 152/55 naval gun is also equipped with two different types of shells, one is an armor-piercing shell, weighing 49.60 kg, with 1.69 kg of powder and a base-delayed fuse. The other is a semi-armor-piercing shell, weighing 44.57 kg, with 5.35 kg of powder and a prompt fuse. After actual combat testing, the destructive performance of the two shells is roughly consistent with the results of the range shooting test, but as mentioned earlier, the shell dispersion value when shooting high-explosive shells is about twice that of armor-piercing shells, and even the latter is only acceptable to the navy. In order to introduce the concept of "rapid firing", the 152/55 naval gun is loaded with brass cartridges when firing (a type of charge is 16.4 kg of NAC gunpowder, used for "reducing gunfire" during conventional shooting or night shooting). During the war, the Navy also seemed to have issued a small number of 152 mm anti-aircraft shells (20 rounds per gun) to the "Vittorio Veneto" class battleships. This is a high-explosive shell with a warhead fuze that can adjust the detonation distance.
The 90/50 naval gun uses a fixed charge with a brass cartridge, weighing 18.41 kg (single charge), and the conventional anti-aircraft shell weighs 10.1 kg and is equipped with a warhead fuze with an adjustable detonation time. The ballistic performance of the 90/50 naval gun in wartime is quite stable and accurate, but in anti-aircraft shooting, the shrapnel produced when the anti-aircraft shell explodes is extremely small, so the effective killing range is quite limited. This defect was later remedied, so the 90/53 anti-aircraft gun also used exactly the same ammunition as it, and the latter has been in service for many years as a land-based anti-aircraft gun. The 90/50 also has corresponding flares, but due to caliber limitations, the illumination intensity and duration that can be provided are quite insufficient.
The aging 120/40 naval gun is specially used for night combat illumination. It uses modified semi-fixed ammunition, which is a brass shell flare weighing 19.76 kg. Although the illumination intensity is better than the 90/50 above, it is limited by the range of the gun itself, and its illumination effect is still limited.
The two small-caliber anti-aircraft machine guns on the "Vittorio Veneto" class battleships-37mm and 20mm guns use standard ammunition of the same caliber weapons of the navy. The 37/54 ammunition weighs 1.63 kg, of which 1.25 kg is the weight of the shell itself. The two types of ammunition of the 20/65 type weigh 0.32 kg and 0.134 kg respectively. The shell was originally made of brass, but later it was changed to special steel (not the widely circulated iron). Different types of shells (high-explosive shells, tracer shells, etc.) were fired alternately during shooting. These shells were equipped with conventional trigger fuses or high-sensitivity fuses. The magazines were loaded in sealed containers and taken out and placed on the loading tray when needed. Under normal circumstances, they were stored in the ammunition cabinet around the machine gun.
The conventional ammunition storage capacity of the "Vittorio Veneto" class battleships is as follows:
381 mm: 495 armor-piercing shells; 171 semi-armor-piercing shells; 4320 powder bags
152 mm: 840 armor-piercing shells; 1428 high-explosive shells; 252 anti-aircraft shells; 2520 brass cartridges. 120 mm: 240 semi-fixed flares. 90mm: 5842 anti-aircraft shells; 50 flares
rounds.
37mm and 20mm: 1500 rounds and 1330 roundsThere is an ammunition depot under each main turret. From the horizontal and vertical sections, it can be seen that each ammunition depot is divided into two compartments, with shells and medicine bags stacked one above the other. The medicine bags are placed on metal racks, while the shells are left in the exclusive "passage well". The gaps in the bulkheads of the ammunition depot are filled, and a fully insulated lighting system is used to control the temperature through strong cold air circulation. In the case of excessive temperature in the cabin, the fire sprinkler system is immediately activated; in order to ensure absolute safety, the damage control center will open the sea valve to quickly flood the entire ammunition depot if necessary, or it can be achieved by manually pulling down the lever on the middle deck.
One is in front of the front engine room, side by side with the two front 152mm turrets and close to the No. 2 main ammunition depot; the other is in front of the rear engine room, side by side with the two rear 152mm turrets. Brass cartridges are stacked on metal racks, and shells are in the "passage well". Illumination shells for 120mm guns are also stored here. The ammunition depots for two small-caliber naval guns are also in the same area. The front room is divided into two spaces, the upper space is used to stack the machine gun’s shell plates, and the lower space is used to stack 90mm shells. The rear room is the same, but the positions of the machine gun shell plates and 90mm shells are swapped. The two ammunition depots are located above and below the rear 152mm ammunition depot. All small and medium-caliber naval gun ammunition depots are equipped with the same facilities and damage control systems as the 381mm ammunition depot.
The loading and unloading of ammunition on the ship are all carried out through the armored openings on one side of the hull. Large-caliber ammunition passes through the three large openings on each side of the main armor plate, and small-caliber ammunition passes through the small openings on each side of the turret deck (selected according to the location of the ammunition depot). Each shell is lifted to the loading and unloading port by a pulley that can extend out of the side of the ship on a slide rail (the shells are usually placed on an ammunition barge moored nearby). After the shell is sent into the hull, it is loaded on a cart that moves along the track. The cart then sends the shell to the shell hoist at the end of the track. The shell is unloaded here by another moving pulley and sent to the ammunition depot, and then placed in the appropriate position through the hanging rail with a clamp. The propellant bags are loaded along the same path, loaded into the cart in groups of six and sent to the ammunition depot. When unloading ammunition, the opposite is done. The loading and unloading of small and medium-caliber ammunition also has a similar process. Due to its small size and weight, the loading and unloading speed is faster. When the ship enters the dry dock, according to the normal process, all the ammunition on board must be transferred to the warehouse on land and loaded back when leaving the port. This process is quite slow and complicated, and all crew members must participate in it. Here is an approximate time, that is, within 60 minutes, each ammunition depot can transfer 15 381mm shells or 150 medicine bags, 150 152mm shells or 120 brass cartridges, and replenish 1,000 90mm shells for two ammunition depots at the same time. Therefore, it takes at least 23 hours to load or unload all the ammunition (including 37mm and 20mm shells) on the "Vittorio Veneto" class battleship.
Steering and anchoring equipment
Rudder and maneuvering
Rudder, the second part of this series discussed the layout of the innovative main and auxiliary rudders of the "Vittorio Veneto" class battleships. In the end, all new battleships were equipped with a semi-balanced main rudder with a surface area of 38 square meters and 16 square meters of auxiliary rudders on both sides that operate independently. The main rudder is located at the very end of the hull’s central axis and can rotate at a maximum angle of 40° along both sides of the rudder axis; a pair of auxiliary rudders are located 25 meters in front of the main rudder and behind the outer twin propellers. The main rudder is driven by a 300-ton electro-hydraulic motor, and the two auxiliary rudders are also equipped with electro-hydraulic motors, but they are smaller and weigh only 80 tons. These motors operate completely independently and can be combined as needed. There are several options:
The rudder angle of the auxiliary rudder is kept at 0°, and only the main rudder is used; the rudder angles of all rudders are kept consistent;
Use the main rudder and only use one auxiliary rudder;
Only use the auxiliary rudder.
Scheme (a) is usually used in normal cruising, while schemes (b) and (c) are used only when sailing at low speed or when it is necessary to pass through restricted waters; using scheme (d) means that the main rudder has been stuck or damaged, and the two auxiliary rudders will take on the function of backup rudders. This flexible and contingency-based rudder use method played an important role during the war, which we will mention in the next article.
There are two steering rooms on the ship, one on the armored bridge and the other under the gun deck. The main rudder uses the traditional "steering wheel" operation, which is connected to the steering gear through hydraulics and cables; the auxiliary rudder is directly operated by the "steering column". In an emergency, all three rudders can be directly operated through their respective steering gear cabins, and even human steering can be achieved with the help of devices when the ship’s speed is not high. The emergency steering station is located in the "mushroom"-shaped superstructure at the stern of the ship. It is mainly used as a command platform and does not have a corresponding steering wheel. However, it can be directly connected to the command bridge, all shooting command centers and fire control centers, engine rooms and damage control centers through cables. All of the above cabins will display the real-time rudder angle of the ship.
The maneuvering characteristics of the "Vittorio Veneto" class battleships are the same as other battleships with large displacement. When the main rudder angle is 35° and the speed is 20 knots, the turning diameter required by the ship is 885 meters, and the time required for a 360° turn is 6 minutes and 35 seconds; at a speed of 29.5 knots, the turning diameter is 935 meters, and the time required for a 360° turn is reduced to 4 minutes and 40 seconds. When executing fleet formation, the rudder angle required for a 180°, 1500-meter turning diameter is: 9° at 10 knots, 9.5° at 14 knots, 11.3° at 18 knots, 13.7° at 22 knots, 17° at 26 knots, and 21° at 30 knots; when the turning diameter is 1000 meters, the rudder angle required is: 22.5° at 10 knots, 23.5° at 14 knots, 25.5° at 18 knots, and 29.5° at 22 knots.
The new battleship was tested for steering performance before it was officially commissioned in 1940, and similar tests were also conducted during the war. In April 1942, the Navy found in a test on the "Littorio" that using the main rudder and the auxiliary rudder on the inner side of the turning direction at the same time when turning would greatly improve the ship’s steering performance. When turning, when the hull is at the maximum tilt angle, the rudder angle of the main rudder is between 209 and 30 degrees. At this time, the main rudder is fully pulled at an efficiency of 5 degrees every 4 seconds. Finally, when moving in reverse, the inner propeller at the stern keeps reversing, the outer propeller stops, the main rudder and the auxiliary rudder are fully pulled, and the ship can reach the minimum turning diameter.
Anchors and anchor winches
The "Vittorio Veneto" class battleship has two "Ansaldo" type modulated steel bow main anchors with hinged anchor claws, weighing 10,410 kg, and the same type of spare second anchor weighing 9,925 kg, all placed in the anchor chain hole on the bow deck; there is also a "streaming anchor" (used for anchoring in river waters) at the stern, weighing 3,500 kg, equipped with a corresponding anchor winch. The two bow anchors are located on the port and starboard sides, equipped with 11 sections (25 meters per section) of 87 mm anchor chain and a 240-horsepower vertical axis electric winch drum, and with anchor chain piles to cope with the situation when anchoring in deep water. The configuration of the spare second anchor is almost the same as the main anchor on the starboard bow. In addition to the heavy mooring chain, there are also some sufficient anchor tying equipment, including: sliding hooks (openable and closable), anchor shackles of various types and sizes, swivels, turnbuckles and two mooring swivels (when mooring, the two main anchors are merged to allow the hull to float freely with the anchor point as the center).
During the construction, the Navy decided to cancel the stern anchor and all its supporting equipment in view of the low possibility of using such mooring. The sea trial results of the first two ships showed that the bow needed to be modified, and the weight of the front part should be reduced as much as possible, so the Navy decided to remove the heavier 11-section anchor chain and its winch of the spare anchor, and only retain the light mooring bollard. Therefore, in May 1940, when the "Littorio" and "Vittorio Veneto" were commissioned, two bow anchors and their supporting equipment were installed, and the spare anchor was firmly tied to the anchor chain hole by a short section of anchor chain; therefore, the spare anchor functioned to replace one of the other two anchors when it was damaged. In the spring of 1941, the "Littorio" removed the spare anchor in March of that year, and then the "Vittorio Veneto" also made the same modification, but the anchor chain hole was retained, and a removable anti-skid plate was added to the forecastle deck to facilitate the crew’s activities when moored.
In the summer of 1942, when the "Roma" was officially commissioned, only two bow main anchors on the left and right sides were installed, as well as the corresponding anchor chain holes, and there were only two anchor winches and anchor chain piles on the forecastle deck. Although the "Empire" was never built, its configuration related to anchors should be equivalent to the "Vittorio Veneto" and "Littorio".
In order to reel in hemp ropes and steel cables, the "Vittorio Veneto" class battleship has three vertical shaft drum winches on the bow, one on the forecastle deck and the other two on the stern deck. There are four 90-horsepower electric hoists on the superstructure to handle two hoisting booms and the folding crane at the stern (used to hoist aircraft onto the catapult).
Main navigation, communication and observation systems
In addition to some magnetic compasses, the "Vittorio Veneto" class battleships also have two "Anhuis" type compasses, whose main systems are located in the armored protection area of the hull’s central axis, one is located in the front, behind the No. 2 turret, and the other is located in the rear middle deck, in front of the No. 3 turret. These two compasses must be activated before the official voyage, and sufficient preparation time is reserved to calibrate the direction. Then the information is transmitted to a large number of repeaters throughout the hull through the connected cables, and finally reaches the command bridge, chart room, emergency steering station and other locations.
The front part of the armored fire control station in the tower supports the platform of the radio direction finder (Siemens OLAP E/404 N type), with a circular antenna, which can achieve the role of auxiliary navigation by detecting radio beacons emitted from the coast, and can also be used to determine the direction of friendly or enemy radio transmissions. The ship is also equipped with a "Spallanz" electromechanical recorder, placed in the front of the hull, for real-time monitoring of speed, repeaters and compasses. Finally, there is a depth recorder in the chart room for detecting water depth: its ultrasonic transducer is installed in the front lower part of the hull.
The "Roma" had reserved space for the installation of a sonar system, which was later installed, but it was removed after the bombing on June 5, 1943, and has never been reinstalled since then.
The radiotelegraph (RT) system on the Vittorio Veneto class battleships consisted of three stations in the citadel:
The main radiotelegraph transmitter station, located slightly forward of the No. 3 turret, was equipped with TN.M 1000 and TN.C. It was located on the middle deck, with 1000/2000 high-power Morse code transmitters.
The main radiotelegraph receiver station was located on the middle deck, forward of the front engine room, with 11 Morse code receivers
.
The secondary radiotelegraph transmitter-receiver station was located in the citadel, below the chart room, with two transmitters (TN.S 1000 and T.AN 250) and five Morse code receivers.
The equipment used for short-range communications was located in the communications center of the citadel, initially a T.A.N type radio. The command bridge is equipped with a shortwave radio and two RA350 radios in the chart room and the auxiliary fire control center. After 1940, the data of the ship’s shortwave and ultra-shortwave radio stations increased significantly, and other types of communication equipment were also added (TP.A.20, R.M.4, etc.). It turns out that these wireless telegraph equipment are reliable and can fully meet the heavy communication needs of officers, but the wireless telephones used for beyond-line-of-sight calls are limited by technical bottlenecks (calibration, power, interference, etc.) and are not satisfactory, sometimes resulting in unstable communication and confidentiality issues. The telephone lines on the "Vittorio Veneto" class battleships are extensive, with 110 telephones integrated into a main line distributed throughout the ship. In addition, there are lines for engines and generators, lines for steering, lines for observation and searchlights, lines for damage control, and other dedicated lines. There is also a command communication line on the ship, connecting a 110-watt amplifier (70 speakers and 5 microphones) and a fire control communication line, which is divided into lines for fire control officers, main guns, small and medium-caliber guns, automatic weapons, etc., with a total of 158 users. All lines are connected to two telephone exchanges fore and aft of the mid-deck
There are three teletypewriters for internal communications on board, installed in the armored cabin behind the admiral’s bridge, the decoding room and the rear radiotelegraph station. There is also a pneumatic mail transmission system between the decoding room in the bridge armored communication center and the main radiotelegraph receiving station. When in port, one of the teletypewriters will be connected to the fixed wire on the shore, either directly if moored at the pier or through a telephone buoy if moored at anchor, so that the ship’s command staff can communicate with the various combat commands on shore.
The signal station is located on a platform behind the command bridge, through which the lower part of the foremast passes; there is a small locker inside for signal flags, which can be hung below the mast by signal flag lines. If necessary, the starboard side of the mainmast spars can also be used to hang signal flags or signal flags, but the port side needs to be reserved for the ball and diamond-shaped "rudder pennants". The ball turning pennant consists of two perpendicular intersecting disks, fixed together by slots, so that it looks like a complete sphere from a certain distance. The diamond turning pennant is also of similar construction. Both turning pennants are painted black and perforated to enhance wind resistance, and are raised and lowered according to the direction of the rudder by a system of steel cables and pulleys (ball turning pennant when turning to port and vice versa).
The signal station communicates directly with the command bridge via telephone, and then connects to the telephone exchange at the front through another instrument. A group of small signal lights are also installed around the guardrail of the tower searchlight platform, which can send signals with white light or blue light with low visibility. The omnidirectional light on the masthead can also send signals in the same way, usually used when moored.
There are a total of 26 fixed observation stations on the ship, all of which are concentrated around the tower. Among them, 16 telescopes are equipped with rotating frames, which can prevent bad weather and avoid the influence of main gun flames. 6 are used for surface observation, 3 on each side of the hull, placed on a small platform with a horizontal height of 32 meters, which can observe targets 32,000 meters away; 6 are located on the top of the command bridge, and another 14 are used to observe aircraft. The observation stations on the ship are divided into multiple groups connected to the universal aiming system. Some air defense observation stations have also been added to the high platform behind the front chimney of the "Roma".
For the lighting system, the Navy stipulated in the late 1930s that the main function of large searchlights was to search and illuminate surface and air targets within the range and assist ships in entering ports at night. After the outbreak of war, it can also be used to illuminate torpedo planes entering the low-altitude dive phase, thereby blinding the eyes of enemy pilots. There are 6 large arc searchlights on the "Vittorio Veneto" class, 4 of which are equipped with lenses with a diameter of 150 cm and weigh 850 kg, and two are equipped with lenses with a diameter of 105 cm and weigh 622 kg. The output power is 19.2 kW and 10.5 kW respectively, the light intensity current is 240 amperes and 150 amperes, the life is 2.5 hours and 2 hours, and it can be remotely controlled and manually controlled. Although the physical characteristics of these searchlights are the same, they are produced by two suppliers. The supplier on the "Vittorio Veneto" is Genoa SG, and the supplier on the "Littorio" and "Roma" is Florence OG. Two of them are located on the searchlight platform of the tower, with slide rails at the bottom, so they can be moved to a position close to the rangefinder tower when necessary; the remaining four are all located on the "mushroom"-shaped superstructure, and two 150 cm ones are equipped with hydraulic lifts.
From the summer of 1942 to the spring of 1943, the "Vittorio Veneto" class began to build a fighter command station to counter enemy air raids. The solution is to set up a command station equipped with the necessary radio system to provide air force officers with a place to observe and command aircraft in real time. Therefore, this command station must be located at the top of the tower, specifically on the platform behind the main fire control, with a small space isolated by waterproof curtains and guardrails. This area is indeed suitable for open observation, but it is far from enough to protect the communication lines connecting the command bridge and the anti-aircraft fire control station. Historical photos show that the command station began to be built in the spring and summer of 1943. The main body is made of metal plates, and the part open to the sky is covered with transparent square hard plastic used on aircraft. The fighter command stations on each battleship had slight differences in size. They were often manned by so-called "fighter operators", as well as some sentinels and communicators. When the Luftwaffe began to intervene, each command station was often staffed by a German officer and several German communicators.
Radar
In August 1941, Littorio became the first Italian battleship to be equipped with a radio rangefinder (called "RDT" by the Italians: Radio-Detector-Telemetro), a term used in conjunction with the more commonly used radio locator ("RaRi"), the latter being the Italian name for early radar equipment. The RDT started as a 70 cm wavelength pulse radar (i.e. "EC3") with two antennas for transmitting and receiving, mounted on the front edge of the bottom rangefinder tower slightly tilted to the starboard side. This radar was derived from a prototype developed in 1936 by the Royal Institute of Electronics and Communications ("R.L.E.C".: Regio IstitutoElettronicodelleComunicazioni). It was later put into practical use by the Naval Academy of Livorno with the assistance of SAFAR, Magneti Marelli, OG, FIVRE and FAMET. Subsequent tests on the early EC3 showed positive results: land-based tests were carried out on April 20, 1941, and soon after, it was installed on the torpedo boat "Giacinto Carini" for shipboard tests, showing that it could indeed detect long-range surface and air targets. Finally, it was installed in the position mentioned above on the "Littorio", about 26 meters above sea level, which significantly improved the efficiency of detecting surface targets. EC3 detects targets in various directions by rotating the rangefinder itself, but due to the obstruction of the stern mast, there will be a large "shadow area" at the stern.
In November 1941, the "Littorio" began to go out to sea to test the EC3 on the ship, but the results were not satisfactory. The main problem was that there was no oscilloscope in the supporting equipment of EC3, which means that the radar echo data is difficult to process. The operator must wear headphones and identify the echo under the influence of the receiver background noise (the echo is composed of sound signals). The environment on the ship is completely different from the environment on land, and these echoes cannot be identified by hearing. In addition, the Navy also believes that EC3 may fail during long-term use and need maintenance, and these failures may not be repaired on the ship. In April 1942, Littorio replaced the EC3’s receiver with a new one equipped with a cathode-ray oscilloscope and tested the second version of the EC3. However, the previous defects were not significantly improved and the equipment itself was still unreliable, so it was decommissioned soon after. During this period, the third version of EC3 "Owl" ("Gufo") began production, which improved the performance compared to the previous version (pulse peak power reached 10 kW, wavelength to 75 cm), and the first batch of "Owl" was produced in the number of 50 units.
After testing in Livorno, the "Owl" was installed on the "Littorio" in Taranto in September 1942, replacing the second version of EC3, but retaining the previous antenna unit (the navy called it "cage" because the antenna unit was similar to a cage-shaped metal cube structure). The transmitter and receiver were housed in separate waterproof light alloy boxes and connected to a J-type oscilloscope in the command post that displayed the echo and distance (the displayed distance was 30 km for surface targets and low-altitude aircraft, and 300 km for air targets). Although the disadvantage of being vulnerable still existed, the new "Owl" was officially put into service. Its performance characteristics were similar to those of the German Fu.Mo The 21/40G radar was similar to the 21/40G radar, which was installed on the destroyer "Legion" in the spring of 1942. The "Legion" was the first Italian ship to be equipped with a non-experimental radar.
In early 1943, considering the urgent needs of the war, the Navy installed early "Owl" radars on several destroyers. It was March when it came to the "Roma", and the "Vittorio Veneto" was not installed until the end of July. The Navy arranged the radar antenna unit on the top platform of the main fire control tower, about 35 meters above sea level. After connecting the motor, it can achieve 360° rotation at three turns per minute to detect a restricted area. Of course, the "Owl" can also manually adjust the detection angle to obtain distance and other readings. In August 1943, the "Littorio" also installed an "Owl" system and put it into use in early September.
The antenna unit installation position was raised, so the detection range of the "Owl" for medium-sized surface targets was increased from 25,000 meters to more than 30,000 meters. At this time, the rotating motor of the "Owl" had an obvious problem. When encountering strong winds, the motor often could not rotate normally due to insufficient power. If the strong wind continued, the motor would stop directly. For this rare problem, it is usually easy to solve it by increasing the power of the motor (or adding a small balancing fin, or even using the new "mattress" rotating antenna that was being designed at the time), but the end of the war in September 1943 was announced by Italy, and the result of the matter was left unresolved. As mentioned above, the performance of the "Owl" (see the data table below) is similar to the slightly older German FU.MO21/40G radar, which uses a "mattress" rotating antenna with a power of 8 kilowatts and a wavelength of 80 cm. But it should be added that the German radar was more reliable and easier to operate than the Italian "Owl".
Some other ships of the Navy, including the "Vittorio Veneto" class, also installed the German Fu.Mb1 "Metox" radar wave detector, which is a simple device with a small cross-shaped antenna unit. "Metox" can detect the same wavelength as the search radar used by British aircraft and will sound an alarm when the ship is irradiated with electromagnetic waves. This is a very sensitive device that can detect even weak signals that are too far away to return as echoes to the antenna that generated them, so it often issues false or very advanced alarms. In addition, under certain conditions,
The "Metox" can amplify the reflected signal, making it easier to locate the radar that emitted the signal. But not long after,
it became ineffective due to changes in the enemy radar frequency, but the Germans quickly improved the radar wave detector, and while improving its performance, they also developed the earliest set of equipment used to interfere with enemy frequencies, thus leading to the original concept of "electronic warfare". In early 1943, German "electronic warfare" specialists would occasionally bring equipment to assist Italian naval ships, but after Italy’s armistice, Germany’s assistance also stopped.
Other shipboard equipment
Shipboard boats, lifesaving equipment and lifting equipment
The "Vittorio Veneto" class originally carried several service boats and lifeboats used by the Italian Navy in the late 1930s, as many as 19 boats: 3 12.25-meter diesel speedboats of two different models, 3 13-meter rowing boats equipped with 25-horsepower auxiliary diesel engines, 2 10-meter and 1 12.25-meter motorboats, 2 8.5-meter motorboats, 2 6-meter motorboats, 1 10.45-meter rowing boat, 1 7.65-meter whaleboat, 2 8.6-meter lifeboats and 2 3.5-meter flat-bottomed workboats. Except for two flat-bottomed boats that were fixed upside down on the forecastle deck, all other ship-borne boats were placed on saddles or pads on the boat deck of the superstructure or the adjacent forecastle deck, and were lowered by two davits installed on the mainmast. Only two 8.5-meter motorboats and two lifeboats were fixed outboard by detachable davits, which were installed slightly in front and behind the 120/40 flare-launching guns on both sides. After the war began, the navy drastically reduced the number of ship-borne boats due to the excessive clutter and safety hazards (such as fires in combat), generally carrying 2 to 3 12.25-meter diesel speedboats, 2 13-meter motorboats, 1 motorboat and several small boats. At the same time, a large number of Cali life rafts that can carry 39 people began to appear on the ship; by 1943, each ship was equipped with an average of 20 such special rigid life rafts, which could carry a total of 780 people; 10 of them were arranged at the front (usually 6 on the top of the No. 1 turret and 4 on the top of the No. 2 turret), and the other 10 were arranged at the rear (6 on the top of the No. 3 turret and 2 on each of the rear secondary turrets). There was no auxiliary machinery on the ship to lower the life rafts. The moorings that fixed them were equipped with release devices, and the life rafts would be released under the water pressure of several meters when the ship sank.
The main davit for lifting the ship-borne boats consisted of two 19-meter-long davits, each with a lifting capacity of 15 tons. They were fixed to the left and right sides of the "mushroom"-shaped rear superstructure, and the jacks were fixed close to the top of the main mast.
@CRDA is producing diesel speedboats for the navy (left), and electric winches produced by "San Giorgio" for ship-borne boats
Smoke generators
In order to release smoke, the "Vittorio Veneto" class is equipped with 10 diesel smoke generators, 4 of which are installed at the bottom of the main boiler exhaust duct of the front chimney, and another 6 are installed at the rear chimney, 4 pass through the main boiler chimney, and the remaining 2 pass through the auxiliary boiler flue. The rear of the main deck is equipped with
The EC3 "Owl" radar carried by the "Vittorio Veneto" class battleships 2~4 smoke generators of the same model, two on each side, which can be remotely controlled. Only the rear smoke generator can be used when docked, and the remaining 10 more effective smoke generators can only be used when the boiler is ignited.
In late 1940, in response to the growing threat of air raids on the anchorage, six sulphuric acid chloroethanol smoke generators were installed to complement the shore smoke generators to increase artificial smoke over the port. These smoke generators are actually gas cylinders with diffuser nozzles that can be remotely controlled; they are mounted on slides and supported by brackets with locks so that they can be quickly thrown into the sea in an emergency. A pair of chemical smoke generators are installed on both sides of the forward anchor winch, another pair is installed slightly forward of the back of the 152 mm turret, and the third pair is installed in front of the rear 152 mm turret. Probably in late 1942, two more of these types of smoke generators were installed on the stern; finally, in the spring of the following year, more such smoke generators were installed on the forecastle deck and the quarterdeck.
Mine sweeping device
Like all large Italian naval ships of the era, the "Vittorio Veneto" class is equipped with defensive minesweeping devices. When sweeping mines, umbrella-shaped minebreakers equipped with cutting blades are placed in the water on both sides of the ship; the minebreakers are connected to the front end of the keel (the perforated steel plate under the bulbous bow) by a strong steel cable. The steel cable unfolds in an inverted "V" shape as the ship moves forward, and can hook, push away and cut off any triggered mines. The mine cable is usually fixed to the seabed hundreds of meters deep. After passing through the perforated steel plate under the bulbous bow, the steel cable of the minebreaker is fixed to the front edge of the forecastle deck.
’Vittorio Veneto" class defensive minesweeping system uses C-type minebreakers (3.3 meters long, 472 mm in diameter at the widest part of the float), which can sweep mines in the 15-meter deep and 75-meter wide area on both sides of the ship. The ship is equipped with 4 minebreakers, two of which are "ready to use" and are deployed and recovered by two special cranes; the crane is fixed on the forecastle deck close to the front of the No. 1 turret and can be moved along the guide rail; the other two are in use and are usually fixed on the buttress of the No. 2 turret. The winch at the front is used to store the minesweeping steel cable required by the crane and assist the crane in recovering the minebreakers. The deployment of the minebreakers is relatively fast, but the recovery is much slower and more laborious. If necessary, the steel cable at the bow can be loosened to quickly discard the minebreakers and their towing cables.
When the defensive minesweeper is deployed, the ship can only sail at medium speed, which will reduce its maneuverability. Therefore, it is wise to deploy torpedo boats in front of the ship or formation, allowing them to use similar but lighter and more flexible minesweepers to clear the mines at a faster speed.
Carrier-borne aircraft
The selection and arrangement of the "Vittorio Veneto" class carrier-borne aircraft have been discussed in the previous article, so this chapter only discusses the carrier-borne aircraft themselves and their service history.
The "Vittorio Veneto" class battleship uses a compressed air catapult of the Gnatto-Barjaggi type, which is composed of steel beams forming a 21-meter-long grid It has a catapult-shaped structure with the axis of rotation placed on the stern centerline, specifically at the very end of the stern. It can rotate 42° to each side of the hull and has two slide rails, making it very easy to identify on the open deck. At maximum power, it outputs a pressure of 80 kilograms per square centimeter. The maximum load-bearing capacity of the traction frame after the aircraft is released is 5,000 kilograms. The maximum braking distance is 2.5 meters after reaching an initial speed of 36 meters per second. From the data, the performance of this type of catapult is better than other domestic catapults in service during the same period, and fully meets the requirements of the only R0.43 seaplane in service at the time (weighing 2,400 kilograms when fully loaded, and having a minimum take-off speed of 99 kilometers per hour). Under normal circumstances, when the hull is fully oriented to port or starboard, the catapult is rotated to the maximum relative wind speed (that is, the sum of the hull sailing forward and the actual wind speed) flowing through the wing. The speed of the aircraft can be combined with the speed of the aircraft itself before taking off, and the aircraft engine can reach the maximum speed a few minutes before takeoff. When the "Vittorio Veneto" class launches R0.43, there is no requirement for the actual wind speed, and the ship can also launch when it is stationary because the catapult itself is powerful.
The "Vittorio Veneto" class has no hangar to accommodate aircraft, and usually carries 3 aircraft. One of them is placed on the traction frame of the catapult, and the other two are placed on the grid bracket under the 381 mm turret and the muzzle. There is also an electric crane responsible for transferring aircraft to the catapult, or for loading and unloading operations in ports and barges. The crane arm is 5 meters long and has a lifting capacity of 5,000 kg. The telescopic column connected to it can be lowered to a position below the main deck. Like other ships with the same layout, carrier-based aircraft placed on the catapult in the open air are affected by the weather and are easily corroded by salt spray and quickly damaged. The main gun flames can also damage the catapult, and the catapult itself can also affect the aiming and firing of the main gun. In wartime, even if the aircraft is fully fueled before takeoff, the risk of fire still needs to be considered. Taking all the above factors into consideration, the aircraft will only be ejected after the battle begins. If the aircraft cannot be ejected immediately during the battle, it will be thrown into the sea. During the war, the captain and officers tend to keep the aircraft on the ship for a long time until the aircraft is really "suitable" to be used, but there are not many opportunities for actual ejection, so the aircraft will inevitably be destroyed.
All carrier-based aircraft in Italy during World War II belonged to the Italian Royal Air Force, and the personnel who actually operated the carrier-based aircraft were naval aviation. A "flying team" was established on the "Vittorio Veneto" class battleship, composed of air force and naval personnel, among which naval officers were part of the R0.43 crew and actually served as captains. These aircraft were almost only used for reconnaissance and rarely for observation and shooting. The regulations stipulate that after completing the mission and reporting by radio, these seaplanes must return to the coastal seaplane base and transfer to the port to which the ship is heading or returning. In theory, they can land on the sea near the ship and be recovered by a crane, but this is usually not done because the aircraft’s range is enough for it to return to the nearest base. In addition, aircraft staying on the sea surface and ships that reduce speed for recovery operations are prone to ambushes by enemy submarines (the lightweight structure of Ro.43 also leads to poor seaworthiness).
Shooting a Ro.43 seaplane. Note that the aircraft has been painted and numbered 922. In the background is an unpainted destroyer
The I.M.A.M RO.43 carried by the "Vittorio Veneto" class battleship is a biplane single-engine seaplane with wings that can be folded backwards. There are main floats under the fuselage and auxiliary floats under the wings on both sides. The whole machine is made of metal and wood. Ro.43 was developed from RO.37. The prototype was produced by the "Romeo Aeronautica" company in Naples, which was a branch of the "Southern Railway (OFM)". Later, it became the "Romeo Aeronautica (IAR)" and finally the "Southern Aeronautical Machinery Industry (IMAM)". Ro.43 made its first flight on November 19, 1934, and later some modifications were made according to the requirements of the Air Force. The first batch of R0.43 seaplanes were carried on the cruisers "Muzio Attendolo" and "Raimondo Montecuccoli" in December 1936 and January of the following year respectively. Although this type of seaplane has good performance, simple and safe operation, it showed poor seaworthiness in the early days of service, which was obvious when landing in level 2 sea conditions. Later, the Air Force found that its metal structure was susceptible to catapults and salt water, so it was designated as a "transitional model" from 1938 to 1940, requiring major Italian aircraft manufacturers to make changes and bid, but it was never replaced.
Between 1936 and 1942, IMAM in Naples and its licensee, Fiat’s CMASA, produced a total of 193 R0.43 seaplanes, including 35 single-seat RO.44 seaplane fighters (non-carrier-based aircraft based on the R0.43). In June 1940, 105 R0.43 seaplanes had been produced, which was the only aircraft that could be used on catapults and ships in Italy at the time. In October 1940, the military ordered a new batch of RO.43 with enlarged tail surfaces (not the so-called "second version of RO.43") to compensate for possible future losses. Some early R0.43s were also modified in this way. Ro.43 was previously code-named "Maggiolino", but later "Grillo" became more widely known because the folded wings looked like a cricket, an insect that jumps around. Although R0.43 has some technical and operational limitations, it is undeniable that RO.43 has played a great role during the war. In the autumn of 1942, the "Vittorio Veneto" class battleships began to carry another type of aircraft, the Re.2000 single-seat fighter. At this point, the aircraft carrying capacity of the new battleship increased from the original 3 RO.43 (specified as 4) to 3 R0.43 and 1 Re.2000. In special circumstances, 2 Re.2000 and 1 Ro.43 can be selected.
Re.2000 is a single-seat, single-engine fighter with an all-metal structure and a full load weight of 2,839 kg. On May 24, 1939, its prototype first flew at Reggio Emilia Airport. A total of 156 aircraft were produced between 1940 and 1942, of which 60 were exported to Sweden and 70 to Hungary, and Hungary obtained a production license. The characteristics of Re.2000 are sturdy, fast and highly maneuverable. Unfortunately, the Air Force is not very optimistic about the prospects of this aircraft, and only a small number of Re.2000s used for interception missions are in service on the front line.
In the spring of 1940, the Navy hoped to carry one or more fighters on the new battleships to assist in the air defense of the ship and deal with the threat of torpedo planes. These fighters could be launched and landed at coastal airports. The Air Force followed the Navy’s proposal and planned to modify 10 Re.2000s for this purpose, but only 8 of them were actually modified. The prototype was a standard interception Re.2000, and the remaining 7 were equipped with a rear cockpit canopy fairing similar to the Re.2000 GA long-range model. In addition, some structures were modified to adapt to the catapult. The modification work took much longer than planned, and it was not until the spring of 1942 that the first "catapulted" Re.2000 was ready for testing. The test was carried out on the old "Giuseppe Miraglia" and the first flight was carried out on May 9, 1942. The launch was not easy because there was no wind and the old support ship from the 1920s was slow. A series of tests were conducted on the new battleships until the first Re.2000 was successfully launched on September 16, 1942, during an exercise in the port of Taranto by the "Vittorio Veneto" and the "Roma".
Although the modified Re.2000s were few in number and had never been used in actual combat, they were of practical air defense significance to the "Vittorio Veneto" class battleships. However, in addition to pilots, the modified Re.2000s could not carry observers that the Navy deemed very necessary. Faced with such a dilemma, the Air Force authorized Reggiani to develop a two-seat aircraft, which was later the Re.2003 that was ready for service in the summer of 1943. One of them was assigned to the air force on September 8, 1943, the same day that Italy announced an armistice with the Allies, and the subsequent Re.2003 was no longer produced; the whereabouts of this aircraft after it was controlled by the Germans are unknown.
By the beginning of 1943, there were 4 Re.2000s assigned to battleships, of which only 2 were capable of action; by the summer, the number increased to 5, of which "Littorio" carried 1, "Vittorio Veneto" carried 2, and "Roma" carried 2. As of the early morning of September 9, 1943, the aircraft carried by the "Vittorio Veneto" class battleships and the subsequent situation are as follows:
"Roma": 2 R0.43MM.27112/27135, 1 Re.2000MM.8263, all sank with the ship;
"Italia" (formerly "Littorio"): two R0.43 unloaded in Malta, probably used for "Giuseppe Miraglia"), one Re.2000 MM.8281, ejected into the sea after being damaged on the afternoon of September 9;
"Vittorio Veneto": two Re.2000s (MM.8264 was destroyed in Ajaccio, Corsica, and MM.8287 was unloaded in Malta and transferred to Italy), it is not clear whether there is R0.43.
From the late 1930s, the numbers on both sides of the Ro.43 fuselage consisted of three parts of numbers, The first black number represents the command (corresponding to the "9" of the 9th Navy Division on the "Vittorio Veneto" class battleships), the second black number is the ship number of the corresponding command, and the third is the number of the single ship. Therefore, the numbers of RO.43 on the three battleships are: "Littorio": 911/912/913; "Vittorio Veneto": 921/922/923; "Roma": 931/932/933.
The numbering of Re.2000 is different from the above. No matter which battleship it is on, it is a red number starting with "1". In addition, It is identified by the black duck painted on the front of the tail. According to the Air Force regulations, from June 1940, the country mark on the tail of carrier-based aircraft was changed from the original vertical tricolor stripes to the Savoy White Cross, and the fuselage was also covered with white stripes in the autumn of the same year. In terms of the overall painting of the fuselage, RO.43 initially used silver-gray aluminum paint, with alternating red and white stripes on the wings. In 1941, it was changed to a dark blue-gray tail surface on the upper part and light gray on the lower wing; the fuselage of Re.2000 has always been dark olive green, and the lower surface has been painted light gray until the armistice.
Crew, shipboard personnel organization and accommodation
According to the 1943 birth According to the content of the effective combat documents on personnel establishment, the number of personnel on board is 1802 ("Littorio"), which varies slightly from ship to ship. If the joint command personnel at the fleet or detachment level are required, the number of personnel on board may increase to 1920~1960.
The joint command is usually composed of the following personnel: the flagship officer and his "deputy flagship officer", the chief of staff, assistant staff officers of different professions (operations, communications, naval engineering, quartermaster, etc.), several junior officers (responsible for the management of various facilities, communication security, etc.), some non-commissioned officers (mainly the quartermaster, radio operator, etc.) and a large number of first-class and second-class sailors.
In addition to the command personnel, there are 77 officers including junior officers and senior officers, 229 warrant officers (first, second, and third classes), 12 civilian personnel (usually kitchen staff), and 1484 non-commissioned officers and sailors on board. Due to various reasons such as promotion and hospitalization, the personnel establishment on board may change by dozens of people.
During service, the captain of this class of ships is a colonel. When in reserve or in a non-combat state due to long-term modification or repair, the captain can command another large warship in combat status and appoint an officer of a lower rank as the "acting" commander. The second commander (deputy captain) is usually a lieutenant colonel. In addition to taking over the captain when necessary, he is mainly responsible for supervising and managing the ship’s personnel and the ship’s logistics organization. The "Littorio" class also has a "third commander" to assist him. The rank of the chief engineer is usually a lieutenant colonel of naval engineering. The ranks of professional officers who manage various branches (artillery, fire control, communication and navigation, navigation, electrical, hull, propulsion, administration, health, etc.) are usually majors or technical majors, and their assistants are junior officers (captains, technical captains, etc.).
In addition to the captain and the second and third commanders, all personnel on the ship are divided into 10 squads, under their respective functional service chiefs, and are organized as follows: Squadron 1 is the navigation and communication (signalman and radio operator) squad; Squadron 2 is the deck squad; Squadrons 3 and 4 are artillery (cannons of various types of artillery) The first detachment (first detachment, second detachment, third detachment) is the naval engineering (stokers, mechanics, engine room personnel, carpenters, etc.) detachment; the 9th detachment is the general affairs detachment (ordinary sailors, quartermasters, etc.); the 10th detachment is the joint command personnel (if stationed on the ship). In addition to officers, some higher-ranking warrant officers (senior boatswains, senior mechanics, senior quartermasters, etc.) and civilian personnel (they are organized differently), all other crew members are divided into three groups to take turns on duty (Group 1, Group 2, Group 3). Under normal circumstances, each group of personnel can cope with all operations on the ship. When at sea, the crew changes shifts every 4 hours within 24 hours according to the shift schedule: from 00:00 to 04:00 (called "second shift on duty" in Italian); from 04:00 to 8:00 (called "wake-up call"); from 08:00 to 12:00 ("standing guard"), and so on. After one group of crew members completes their watch, they are taken over by the next group of crew members who got off duty 8 hours ago, and after the latter group of crew members completes their 4-hour watch, they are taken over by the next group of crew members who got off duty 8 hours ago. The basic pattern is 4 hours on duty and 8 hours off. When sailing for a long time, in order to avoid repeating the same schedule for duty, the first round of duty (16:00 to 20:00) is divided into two rounds of two-hour duty, called the first and second "night shifts" respectively. Alarms at the "combat post" or "maneuvering post" or other emergencies will obviously break this cycle; all crew members will be mobilized and assigned specific tasks according to each person’s position (combat, maneuvering, firefighting, deck cleaning post, ammunition loading and unloading, abandoning ship, etc.). The pattern of 4 hours on duty and 4 hours off is mainly arranged for Young students and midshipmen, but some professionals also adopt this duty mode. During the port call, the service demand is reduced. The crew members are on duty according to the arrangement every day. After get off work, they can go ashore for a few hours, but they are not allowed to leave the base, so that free activities can be cancelled when necessary (bad weather, unplanned sea orders, etc.), and all crew members can be recalled by various methods. Only with temporary certificates and during ordinary or special holidays (seldom allowed) can the crew leave the ship and the base for more than one day.
The crew’s cabins and their respective bathing and toilet facilities are mainly concentrated in the front, and there are also small parts in the middle and rear. The accommodation is used as both sleeping and dining space. The "beds" (hammocks) were hung in rows on movable struts and in the morning were rolled up (with mattresses, sheets and blankets rolled into cylinders and then tied tightly together) and placed above their respective lockers against the bulkhead. The dining table and chairs were placed in areas where there were no hammocks and were dragged into the hatch space at night. This arrangement originated in the sail era and although it was not very convenient, it saved a lot of space and made the quarters orderly and easier to clean. This practice was maintained in the Italian Navy until the 1960s, when it was gradually replaced by standard and more comfortable fixed berths and separate dining facilities based on the experience of American warships after the war.
Warrant officers’ accommodation was small compartments with berths, mainly arranged below the forecastle deck, and a few in the stern. Single and double rooms for officers were arranged in the stern and stern. For the flagship officer, the captain and the deputy captain, there was ample space below the fore main deck, including meeting rooms, administrative space, etc. Many trainee officers lived in a small dormitory at the rear of the middle deck.
The main logistical facilities, including the bread oven, are arranged in the central superstructure, where there are also kitchens for sailors, non-commissioned officers, officers and captains, providing meals to their respective service objects. There is a large officer’s living room in the rear superstructure, which can be used as a canteen and as a lounge at other times; there is also a small living room with similar functions for senior officers; the canteen for warrant officers is arranged below the forecastle deck.
The meals at that time were not served in the form of buffets like today (it was not introduced into the Italian Navy until the 1950s), and ordinary crew members (non-commissioned officers and sailors) were divided into 6 to 10 people. Each canteen has a public pot and its own tableware; the "canteen" of each canteen group takes turns to assign two crew members to take meals from the kitchen and wash the tableware.
The normal storage of fresh and frozen food in the food storage rooms and cold storage of the "Vittorio Veneto" class can be used for about two months for 1,500 people on board.
Hull painting
When the "Littorio" and "Vittorio Veneto" were officially commissioned in May 1940, they adopted the navy’s standard light gray paint, covering the hull except the superstructure and the top of the chimney cover; the upper deck was the conventional dark lead gray; the rear deck was paved with teak strips and was not painted. According to the standard, the bottom of the hull needs to be sprayed with a layer of anti-rust primer, and then hot-sprayed with two layers of dark green paint, respectively for anti-corrosion and anti-fouling. The reason why the Italian Navy chose light gray as the standard paint color is because it has a tendency to "change color", specifically, light. But if the weather is clear and the sea gray absorbs the main color of the environment and produces a "shadow", it will be a bright white when observed from a distance, which will create a strong contrast with the sea blue. The reason why the dark gray (lead gray) is chosen to be sprayed on the deck is that the shadow it produces is easier to blend into the sea surface. In any case, any white and fast ship is very easy to be detected by aircraft.
In July 1940, the Italian Navy began to modify the paint of the ship because in the earlier Battle of Cape Stino, the Air Force’s aircraft could not quickly identify enemy and friendly ships. So it was decided to spray red and white stripes alternately on the forecastle deck, with the bow centerline, spraying from -45° on the left to +135° on the right. According to the relevant instructions, the sterns of the "Littorio" and "Vittorio Veneto" also needed to be painted with these red and white stripes until the beginning of 1943. The stripes on the bow of the "Roma" were retained from beginning to end, and the wooden deck of the stern was sprayed in the dark gray mentioned above.
The experience of World War I showed that under normal circumstances, the camouflage paint of the hull (the camouflage paint) Therefore, the significance of camouflage paint in the 1930s was to "disguise" ships, change the appearance of ships, and confuse the enemy’s judgment of the course of our ships, rather than relying entirely on a certain color to conceal ships at sea. This idea is outdated and wrong. However, Lieutenant Luigi Petrillo of the Italian Navy Engineering Department hopes to integrate the color and style of camouflage paint, that is, to consider a variety of lighting conditions and use statistics to find the most suitable color combination, so that the ship looks less conspicuous, and at the same time, the color contrast plays a camouflage role.
In early 1941, the Navy tested some camouflage paint on the Fiume and the Duke of Aosta. At the end of March 1941, the Littorio needed to be repainted after repairing the damage of the "Night of Taranto", so it adopted the same scheme as the Duke of Aosta, that is, spraying the "double fishbone" pattern on both sides of the hull. In June of the same year, the "Vittorio Veneto" that survived the Battle of Cape Matapan also adopted a similar spraying scheme, but the pattern was different. In the summer, the bows and sterns of the two battleships were painted matte gray-white to mislead distant enemy observers about the length of the hulls, and to simulate the shape of the splashes to confuse the enemy’s assessment of the true speed of the ships. The purpose of this camouflage coating is to reduce the visibility of the ship itself, making it difficult for equipment such as rangefinders to determine the speed and heading angle. In fact, the contrast between the two colors is not great, resulting in a clear black outline of the hull.
The Navy tried a variety of patterns and colors (light gray and dark gray, yellow, white, etc.), but the effect was not very good, and finally decided to use only light gray and dark gray. The specific method is: use light gray as the base color, and superimpose dark gray right-angle geometric figures or irregular figures on it. The test began on the cruiser Bande Neri in October 1941, and the results were basically satisfactory. Therefore, on December 29, 1941, the Italian Navy officially issued the "Royal Navy Ship Camouflage Coating Guidelines", which stipulated that the camouflage coating should only use a combination of gray and white, that is, matte light gray and matte dark gray, and matte gray-white only for the bow and stern. At the same time, it was stipulated that the irregular pattern of the dark part "should not show horizontal or vertical lines, and avoid long continuous parallel lines", "as much as possible, the pattern on both sides of the hull should not be the same". According to the guidance of the guidelines, in March 1942, the "Vittorio Veneto" was completely repainted with camouflage paint, that is, the patterns on both sides of the hull were different and irregular, and the bow and stern were also sprayed with matte gray-white. In May of the same year, the "Littorio" was also modified accordingly. On June 14, 1942, the Roma was officially delivered to the Navy by C.R.D.A., and in the final stage of the Trieste shipyard, it was painted with the Navy’s first "standard camouflage paint" in a strict sense. In the summer and autumn of 1942, the matte gray-white color of the bow and stern of the Vittorio Veneto and Roma was changed to the same matte light gray as the base color.
The Empire did not have its own camouflage paint, but was painted with some paint that could blend into the environment during the transfer process (Brindisi, Venice and Trieste).
In 1944, the camouflage on the Littorio and Vittorio Veneto was covered with a uniform matte light gray, and the horizontal armor belts were painted with horizontal matte dark gray stripes. This paint scheme is somewhat similar to the scheme of British and American naval ships during World War II until it was retired in 1948.
To be continued
