23/6/2020 [1.99.0.11] Minengeschoß shell for Japanese 20 mm Ho-5 cannon

[tester188@psn 1,413]

1. The full name of the vehicle affected.

 

 Affects all Japanese Army aircraft equipped with 20 mm Type 2 Army Ho-5 cannon.

 

2. A detailed description of the issue you have or what you see as being erroneous regarding its representation in-game.

 

Historically, the Imperial Japanese Army Air Force was influenced by Luftwaffe and imported Bf 109 E-7, Fw 190 A-5 and MG 151/20. And imported a lot of Minengeschoß shell and used it in Ki-61-I Hei. You can see it in War Thunder as well. IJAAF is interested in Minengeschoß for MG 151/20 and has copied it for use with a 20 mm Ho-5 cannon. The Japanese copy of Minengeschoß was designated as Usuniku-ryūdan (薄肉榴弾 thin-walled HE shell). However, in the game, Ho-5 cannot use Minengeschoß.

 

You can already see the Minengeschoß in the Japanese Air Tree.

• Bf 109 E-7 (MG FF/M)

Spoiler

 

• Fw 190 A-5

Spoiler

 

• Ki-61-I Hei

Spoiler

 

• Ki-61-I Hei Tada's

Spoiler

 

Ho-5 cannon has only three types of ammunition.

• AP-T
• HEF-I
• Practice (?)

Spoiler

 

 

 

 

3. A detailed description of the fix you suggest. Provide sources including reference that underline your position. This is up to the discretion of the Technical Moderator handling the report, however the number of sources required depends on the type of source presented:

 

I suggest adding Minengeschoß to the belt combination for the Ho-5 cannon. According to the source it is a copy so the spec is the same as Minengeschoß for MG 151/20. Since it was a relatively small number of production, a smaller number than MG 151/20 is acceptable. Please consider.

 

Sample

• Air targets belt
• AP-T/HEF-I/HEF-I/HEF-I/HEF-I/HEI (Minengeschoß)

 

Sources

Website / "expert" opinion

Quote

According to the testimony of a veteran who was a member of the Army Aviation Technical Department:

"Mauser cannon (translator's note: MG 151/20) had an ammunition called Thin-walled HE shell (translator's note: Minengeschoß). This increased the blast effect by increasing the filling capacity by making the wall of the projectile thinner. Another was the self-destroying HE shell. It was designed to explode in the air after 3 seconds if the shell did not hit the target. At our Army Air Force, we have copied a thin-walled HE shell for the Ho-103 and Ho-5 cannons. It suffered from lack of resources and technology, but was adopted as an official weapon. However, when we tried to mass-produce it, the war was over and the purpose was not fulfilled."

 

マウザー２０mm機関砲

「弾薬の一種に薄肉榴弾と称し、弾肉薄く収容炸薬量を大ならしめ、其の榴弾的効果を大ならしめたる外、自爆信管と称し、敵機に命中せざる場合は一定時間後（約３秒）空中に於いて自爆する如く設計せらたるものである。陸軍航空に於いては之を模倣し、「ホ５」用及「ホ１０３」用薄肉榴弾を試作せるも、材料不良及び技術低位なるため、種々の困難に遭遇したが兎に角制式弾の一部として制定、多量整備に移行せんとしたのであるが、目的を果たさざるに終戦となったのである。」

Yasufumi Kunimoto, Japanese firearm history researcher

http://www.warbirds.jp/kunimoto/type51/Riku16.htm

 

The above source are taken from the official military history, "History of Army Aviation Technology" (陸軍航空技術沿革史). It has not yet been published on the internet. @Lineins took a picture and shared it with permission at the Archives. The cover is here.

 

Ammunition production plan list

Spoiler

 

 

マ二〇六: Ma-206

(薄肉榴弾四式剛発信管付): (Thin-walled HE shell with Type 4 low sensitivity air column fuze)

Ammunition for aircraft. Creator: Army Ordnance Administration Head Office. 1944

https://www.jacar.archives.go.jp/das/meta-en/C13120840300

 

Research report

Spoiler

 

The 20 mm thin-walled HE shell for aviation has succeeded in obtaining a good function. However, during the transition to mass production, a premature explosion at the muzzle occurred, and we succeeded in changing the design again and getting the perfect one. In addition, we have completed basic research on the 13 mm thin-walled HE shell for aviation and succeeded in obtaining a good-functioning shell.

航空用２０粍薄肉榴弾ハ機能良好ナルモノヲ得多量生産ニ移行中ナリシモ腔発過早発発生セルニ鑑ミ再度設計変更シ完璧ナルモノヲ得タリ 尚航空１３薄肉榴弾ハ基礎研究完了シ機能良好フルモノヲ得タリ

7. Ground weapon (3) / Principal study actual situation table Army Ordnance Administration Head Office. August 31, 1945.

https://www.jacar.archives.go.jp/das/meta-en/C13120846400

 

A production record of ammunition submitted from Japan to the United States after the end of the war.

Spoiler

 

The 20 mm Type 4 HE shell has a "thin-walled" (薄肉) annotation. 

 

 

二式20粍徹甲弾弾丸体: Type 2, 20 mm AP-T projectile body

二式20粍榴弾弾丸体: Type 2, 20 mm HE-I projectile body

四式20粍榴弾弾丸体 (薄肉): Type 4, 20 mm HE projectile body (thin-walled)

A survey of important ammunition works, equipment, and installations (private industry section) report made by Army ordnance administration headquarters. Report No. 45c(1), USSBS Index Section 2. p. 3, 6.

https://dl.ndl.go.jp/info:ndljp/pid/8818407?itemId=info%3Andljp%2Fpid%2F8818407&__lang=en

 

A production record of ammunition submitted from Japan to the United States after the end of the war.

Spoiler

 

The Type 4 HE (thin-walled) shell that copied Minengeschoß from MG 151/20 to 20 mm Ho-5 cannon was produced 50,000 rounds in 1944 and 100,000 rounds by August 1945.

Amount of arms, shells, and motor vehicles production chart. Report No. 45q(14), USSBS Index Section 2. p. 8. 

http://dl.ndl.go.jp/info:ndljp/pid/8818497?itemId=info%3Andljp%2Fpid%2F8818497&__lang=en

 

Reference

Information on MG 151/20 and Minengeschoß imported by the Japanese Army.

 

History of Minengeschoß

https://warthunder.com/en/news/3052--en

2020_05_27_11_44_36__9268.clog

Edited May 29, 2020 by *tester188

[Rapitor 10,702]

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