Type 4 20 cm rocket launcher
| Type 4 20 cm rocket launcher | |
|---|---|
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|
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| General Information | |
| Military designation: | 四 式 二 〇 糎 噴 進 砲 |
| Manufacturer country: |
 Japan
|
| Development year: | 1943 |
| Production time: | 1944 to 1945 |
| Number of pieces: | 1800 |
| Weapon Category: | Rocket launcher |
| Technical specifications | |
| Pipe length: | 1.92 m |
| Caliber : |
203 mm |
| Weight ready for use: | 228 kg |
| Elevation range: | +40 to +65 degrees |
| Side straightening area: | 300 ° |
| Furnishing | |
| Ammunition supply: | individually |
The Type 4 20 cm rocket launcher ( Japanese 四 式 二 〇 糎 噴 進 砲 , Yon-shiki nijissenchi funshinhō ) was a rocket launcher that was used by the Imperial Japanese Army during the Pacific War from 1944 to 1945. The designation Type 4 indicates the year the troops were introduced, the year Kōki 2604 or 1944 according to the Gregorian calendar.
history
In the course of the Pacific War , the Japanese became more and more aware of their artillery inferiority compared to the Allies . To compensate for this, they developed rocket launchers for close support, with which they had had good experiences. Due to their low weight compared to guns and howitzers , they were much more mobile than the latter and still had considerable firepower. Due to the growing scarcity of raw materials in the Japanese Empire , it was also easier for Japanese industry to manufacture rocket launchers, which basically consisted of a barrel and a bipod , than to produce time-consuming and complicated guns. But as with many other Japanese military projects, the aversion between the army and the navy was one reason why both branches of arms developed their own 20 cm rocket launchers and thus wasted resources necessary for war.
Delivery of the Type 4 warheads began in August 1944. By the end of the year, 2900 warheads had been produced, in 1945 there were 6900. The production of the launchers with bipods was around 1800.
Calls
The Type 4 20cm rocket launcher was the only Japanese rocket launcher in World War II that was used during combat operations. During the Allied retaking of the Philippines , the 3rd Missile Artillery Battalion was stationed on Luzon and used the missile launcher. Some Type 4 or their projectiles were used in the defense of Iwojima and Okinawa .
technology
The type 4 was basically built like a mortar ; an approx. 2 m long pipe was held by a bipod, while the lower part of the pipe rested on a kind of floor plate that was below the pipe (and not behind the pipe, otherwise the jet of fire from the propellant charge would have damaged the floor plate). A horizontal and vertical rotating mechanism served as the aiming device. A special feature of type 4 is that only the upper part of the tube is the actual barrel. To load Type 4, the lower part of the tube was folded halfway up so that the bullet could be inserted into the lower open half. The tube was open at the bottom. After loading the type 4, the opened tube half was folded down and closed with the help of two quick-release fasteners. The Type 4 20 cm rocket launcher fired a twist- stabilized projectile with a weight of 83.7 kg (Army version) or 85 kg (Marine version). While the front part of the projectile contained the warhead, seven rocket propellants were mounted in the lower part: one in the middle and the remaining six around the middle one. The warhead and the rocket propellant were connected with screws. The lower plate of the rocket propellant charge had six holes drilled into the plate at an inclined angle to give the projectile a spin and increase its flight stability. The 16.5 kg (Army version) or 17.5 kg (Marine version) filled with explosives warhead could be fired up to 2400 m (Army version) or 1600 m (Marine version).
An electrically triggered detonator was initially used to fire the projectile, which required battery operation. In order to do without the battery solution, however, a friction igniter prevailed, which triggered the propellant charge. The seven rockets then released a six to nine meter long jet of fire, which shot the rocket from the launcher and which lasted the first 100 meters of the flight. When it was shot down, no smoke was produced, but a lot of dust was blown up. The bullet's trajectory could be observed both from the point of launch and from the area of impact.
If no launcher tube was available, wooden and bamboo frames were used or a hollow was dug in which a recess was dug in the direction of flight.
Technical specifications
| Type 4 of the army | Type 4 of the Navy | |
|---|---|---|
| caliber | 203 mm | 210 mm |
| Pipe length | 1.92 m | 2.00 m |
| Elevation range | + 40 ° to + 65 ° | + 40 ° to + 65 ° |
| Side straightening area | 300 ° | 300 ° |
| Gun weight | 228 kg | 200 kg |
| Bullet weight | 83.7 kg | 85 kg |
| Muzzle velocity V 0 | 175 m / s | ? |
| Maximum range | 2,700 m | 1,800 m |
Hit accuracy
After the end of the war , most Japanese weapons were examined by the US Army for their suitability and effectiveness. In the case of type 4, several test shots were fired, the impact of the projectiles being within a 91 m long and 82 m wide rectangle with a range of approx. 2700 m.
Versions
- Type 4 20 cm rocket launcher of the army
- With bipod
- On a light carriage with two wheels
- As a multiple rocket launcher (3 projectiles side by side on wooden carts)
- Type 4 20 cm rocket launcher of the Navy
Preserved copies
- In the Yasukuni Shrine , a type-4 copy is received
literature
- Steve J. Zaloga: Defense of Japan, 1945 (= Fortress. 99). Osprey Publishing, Oxford et al. 2010, ISBN 978-1-84603-687-3 .
- Leland Ness: Guide to Japanese Ground Forces 1937–1945: Volume 2: Weapons of the Imperial Japanese Army & Navy Ground Forces Helion & Company, 2014, ISBN 978-1-909982-75-8 .
- Chris Bishop: The Encyclopedia of Weapons of World War II Metrobooks, 2002, ISBN 978-1-58663-762-0 .
Web links
- Type 4 8 '' rocket launcher. Taki's homepage, accessed on June 20, 2016 (English).
- Japanese Field Artillery. (PDF; 4.7 MB) US Military Division of the War Department, accessed on April 14, 2016 .
- Japanese Infantry Rocket Artillery of World War II. YouTube, accessed April 14, 2016 .