In 1914, the 76, 2-mm "dual-use" Type 3 cannon entered service with the Japanese fleet. In addition to fighting the "mine fleet", another purpose of the gun was to fire at air targets.
Marine 76, 2mm gun Type 3
By the beginning of World War II, these guns had mostly moved from the decks of Japanese warships to the shore. Cannons Type 3 were actively used in the defense of the islands. And although theoretically they could fire at air targets with a rate of fire of 10-12 rounds / min at an altitude of up to 7000 m, in practice the effectiveness of such fire was low due to the lack of fire control devices and centralized guidance. That is, these guns could only fire barrage.
The first specialized anti-aircraft gun in the Japanese armed forces was the 75-mm Type 11 anti-aircraft gun. The designation of this gun suggests that it was adopted in the 11th year of the reign of Emperor Taisho (1922).
A number of borrowings from foreign designs were implemented in the gun, including many parts copied from the British 76, 2 mm Q. F. 3-in 20cwt anti-aircraft gun.
Anti-aircraft 75-mm guns Type 11
However, due to a lack of experience, the gun turned out to be expensive and difficult to manufacture, and the accuracy and firing range turned out to be low. The height reach at an initial speed of 6, 5-kg projectile 585 m / s was about 6500 m. A total of 44 anti-aircraft guns of this type were fired.
Despite their small numbers, Type 11 anti-aircraft guns took part in a number of armed conflicts and remained in service until at least 1943.
In 1928, the 75-mm Type 88 anti-aircraft gun was put into production. The 1928 year of the adoption of the Type 88 gun into service corresponds to 2588 “from the founding of the empire”. Compared to the Type 11, this was a much more advanced gun, although the caliber remained the same, it was superior in accuracy and range to the Type 11. The gun could fire at targets at altitudes up to 9000 m, with a rate of fire of 15 rounds / min.
75-mm anti-aircraft gun Type 88
However, this weapon was not without its drawbacks. Particularly inconvenient for deploying an anti-aircraft gun in a combat position was such a structural element as a five-beam support, in which it was necessary to move four beds apart and unscrew five jacks. Dismantling the two transport wheels also took time and effort from the calculation.
But the main drawback of the gun was revealed already during the war - it had a small reach in height. The Type 88 anti-aircraft gun was ineffective against the American B-17 bombers and absolutely ineffective against the B-29.
Japanese 75 mm Type 88 anti-aircraft gun captured by the Americans in Guam
The hope of the Japanese command to use the Type 88 cannon as a powerful anti-tank weapon also did not materialize. During the landing of American troops and equipment on the islands of the Pacific Ocean, the coastal zone was so thoroughly and generously processed by ground attack aircraft and naval artillery shells that the bulky guns simply could not survive.
During the fighting in China, Japanese troops captured 75 mm Bofors M29 guns. After it became clear that these guns are significantly superior in service and combat characteristics to the Japanese Type 88, it was decided to copy the Bofors M29. Production of the new anti-aircraft gun, designated Type 4, began at the end of 1943. The height of the fired targets increased to 10,000 m. The gun itself was more technologically advanced and convenient for deployment.
75-mm anti-aircraft gun Type 4
Due to the incessant raids of American bombers and a chronic shortage of raw materials, it was possible to produce about 70 75-mm Type 4 anti-aircraft guns. All of them were located on the territory of the Japanese islands and for the most part survived until surrender.
In addition to its own 75-mm anti-aircraft guns, the Imperial Japanese army used the British 76, 2-mm Q. F. 3-in 20cwt anti-aircraft guns captured in Singapore, as well as single copies of the American 76, 2-mm M3 anti-aircraft guns. However, both of these guns by the end of the 30s were considered obsolete and did not represent much value.
During the Second Sino-Japanese War, in Nanjing, Japanese troops captured German-made 88-mm naval guns. Realizing that the 75-mm Type 88 anti-aircraft guns no longer fully meet modern requirements. The Japanese military leadership decided to launch this weapon into production. It entered service in 1939 under the designation Type 99. From 1939 to 1945, about 1000 guns were produced.
88-mm anti-aircraft gun Type 99
The Type 99 anti-aircraft gun was significantly superior to the 75-mm anti-aircraft guns.
A fragmentation projectile weighing 9 kg left the barrel at a speed of 800 m / s, reaching an altitude of more than 10,000 m. The effective rate of fire was 15 rounds / min.
For the 88-mm Type 99 anti-aircraft gun, a convenient carriage for transportation was not developed. In case of redeployment, the disassembly of the gun was required, therefore the 88-mm Type 99 guns, as a rule, were located at stationary positions along the coast, simultaneously performing the functions of coastal defense guns.
By the time hostilities began in the Pacific theater of operations, the Japanese air defense system had about 70 100-mm Type 14 anti-aircraft guns. The gun was put into service in the 14th year of the reign of Emperor Taisho (1929 according to the Gregorian calendar).
100-mm anti-aircraft gun Type 14
The height of target destruction with 16-kg Type 14 projectiles exceeded 10,000 m. The rate of fire is 8-10 rds / min. The mass of the gun in the combat position is about 5000 kg. The base of the implement was supported by six paws, which were leveled by jacks. To remove the wheel travel and transfer the gun to the firing position, the crew took 45 minutes.
The advantage of the combat characteristics of the 100-mm Type 14 guns over the 75-mm Type 88 was not obvious, and they themselves were much heavier and more expensive, and soon the 75-mm anti-aircraft guns replaced the 100-mm in production. During the war, all guns of this type were deployed on the island of Kyushu.
In the mid-30s, simultaneously with the beginning of the design of an air defense destroyer in Japan, the development of a new 100-mm anti-aircraft gun began. The already existing naval 127-mm guns did not meet the requirements due to too small reach in height and insufficient rate of fire and aiming speed.
100-mm gun mount on the Akizuki-class destroyer
An artillery system with two such guns was put into service in 1938 under the name Type 98. Its copies were installed on the Akizuki-class destroyers. For the armament of large ships, a semi-open installation Type 98 model A1 was developed, but it was used only on the Oyodo cruiser and the Taiho aircraft carrier.
In early 1945, guns intended for unfinished warships were installed on coastal stationary positions to protect against American B-29 strategic bombers. These were not many Japanese anti-aircraft artillery systems capable of effectively countering the B-29. However, the effectiveness of anti-aircraft fire was reduced due to the lack of shells with a radio fuse and an insufficient number of PUAZO and radar stations for the Japanese.
Within the framework of military-technical cooperation in 1941, Japan received from Germany technical documentation and samples of the 10.5-cm Flak 38 anti-aircraft gun from Rheinmetall. These were quite sophisticated weapons for their time, capable of firing at targets at an altitude of more than 11,000 m. But for a number of reasons, mainly due to the overload of factories with military orders and a lack of raw materials, their production was never established. On the basis of the Flak 38, Japan developed a 105 mm Type 1 anti-tank gun, the production of which was limited to single copies.
In 1927, the 120-mm Type 10 gun (10th year of the reign of Emperor Taisho) entered service, which was developed as a coastal defense and anti-aircraft gun. Before that, there was a naval version of the gun, some of the naval guns were converted into anti-aircraft ones. In total, more than 2,000 Type 10 guns were produced.
120-mm Type 10 gun captured by the Americans on the island of Guam
A gun weighing 8, 5 tons was installed in stationary positions. Rate of fire - 10-12 rounds / min. The muzzle velocity of a 20 kg projectile is 825 m / s. Reach 10,000 m.
Japanese 120mm Type 10 gun captured by the Americans in the Philippines
In 1943, production of the 120mm Type 3 anti-aircraft gun began.
The leadership of the Imperial Japanese Army had high hopes for the new anti-aircraft gun. It was supposed to replace the 75-mm anti-aircraft guns in mass production, the effectiveness of which had already become insufficient.
120-mm anti-aircraft gun Type 3
The 120-mm Type 3 anti-aircraft gun was one of the few anti-aircraft guns that could effectively fire at B-29 bombers, which carried out devastating raids on cities and industrial enterprises in Japan.
A fragmentation projectile weighing 19, 8 kg was accelerated in a barrel length of 6, 71 m (L / 56) up to 830 m / s, which made it possible to fire targets at an altitude of over 12,000 m.
However, the gun itself turned out to be quite massive, the weight in the firing position was close to 20 tons, which seriously reduced the mobility of the system and the ability to quickly relocate. These guns, as a rule, were deployed at prepared stationary positions. The guns were mainly deployed around Tokyo, Osaka and Kobe.
Anti-aircraft 120-mm guns Type 3 proved to be quite effective, some of the batteries were coupled with radars.
In 1944, Japanese specialists managed to copy and set up production of the American SCR-268 radar. Even earlier, on the basis of the British radars captured in Singapore in October 1942, the production of the "41" radar was set up to control anti-aircraft fire.
SCR-268 at Guadalcanal. 1942 year
The station could see aircraft and correct anti-aircraft artillery fire at explosions at a range of up to 36 km, with an accuracy in a range of 180 m and an azimuth of 1, 1 °.
With the help of 120-mm Type 3 anti-aircraft guns, the Japanese managed to shoot down or seriously damage about 10 American B-29s. Fortunately for the Americans, the number of these guns in Japan's air defense was limited. From 1943 to 1945, only about 200 anti-aircraft guns were produced.
After the start of regular raids by American bombers, the Japanese command was forced to use 127-mm Type 89 naval guns to strengthen the air defense of land targets.
127 mm Type 89 cannon
Weapons weighing more than 3 tons in a combat position were installed at stationary fortified positions. A projectile weighing 22 kg and an initial speed of 720 m / s could hit air targets at an altitude of 9000 m. The rate of fire was 8-10 rounds / min.
In total, more than 300 127-mm guns were permanently mounted on the shore. Most of them were located in areas of naval bases or along the coast, thus providing antiamphibious defense.
Some of the guns were installed in two-gun naval towers, protected by anti-splinter armor.
The most powerful Japanese anti-aircraft gun was the 150-mm Type 5. It was supposed to be more effective than the 120-mm Type 3. Its development began when it became clear that the B-29 was capable of flying at altitudes of over 10,000 m.
150-mm anti-aircraft gun Type 5
To save time, the project was taken as a basis for the 120-mm Type 3 gun, the caliber and dimensions of which were brought to 150-mm, with a corresponding increase in the firing range and firepower. The project was completed very quickly, after 17 months the new anti-aircraft gun was ready to fire.
The muzzle velocity of the 41-kg projectile that left the 9th barrel was 930 m / s. This ensured the shelling of targets at an altitude of 16,000 m. With a rate of fire of up to 10 rds / min.
Before the surrender of Japan, two guns were produced, which were successfully tested in battle. They were stationed on the outskirts of Tokyo, in the Suginami area, where on August 1, 1945, two B-29s were shot down. Until the end of hostilities, American bombers avoided flying over the area, and these powerful anti-aircraft guns no longer had a chance to prove themselves.
In the post-war American materials of the investigation of this incident, it is said that such effective shooting is largely due to the fact that these two guns were coupled with a Type 2 fire control system. It was also noted that the shells of the 150-mm Type 5 guns had twice the radius of destruction compared to the 120-mm Type 3.
In general, evaluating the Japanese anti-aircraft air defense systems, one can note their diversity. This inevitably created big problems in the supply, maintenance and preparation of calculations. Most of the anti-aircraft weapons were frankly outdated and did not meet modern requirements.
Due to insufficient equipment with fire control systems and stations for detecting air targets, a significant part of Japanese anti-aircraft guns could only conduct non-aimed, defensive fire.
Japanese industry was unable to produce effective anti-aircraft guns and fire control systems in the required quantities. Among the leading countries participating in World War II, Japan's air defense systems turned out to be the smallest and most ineffective. This led to the fact that American strategic bombers carried out raids in the daytime with almost impunity, destroying Japanese cities and undermining industrial potential. The apotheosis of these daytime raids was the nuclear bombing of Hiroshima and Nagasaki.
