# Explain these WWII Japanese naming conventions, please. . . **URL:** \ **Category:** Factual Questions\ **Created:** [November 23, 2010, 3:52pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663 "2010-11-23T15:52:58Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [November 23, 2010, 3:52pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/1 "2010-11-23T15:52:58Z")
In English anyway, the Japanese submarines are “I-[some number].” Did the Japanese actually use the letter “I” in their names, and if so, why not some similar Japanese word, syllable, whatever? We learn that Midway Island was referred to as “Island AF” in Japanese communications. Presumably the word “island” was a Japanese word or code word for the same, but why would the Japanese be referring to some location with the letters “A” as opposed to some Japanese coding. [I don’t speak Japanese, but I am familiar with some of their syllabary conventions.] ---
**Author:** ![mlees](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@mlees](https://boards.straightdope.com/u/mlees)\ **Post date:** [November 23, 2010, 5:00pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/2 "2010-11-23T17:00:57Z")
It’s just a hull number. [Submarines of the Imperial Japanese Navy - Wikipedia](http://en.wikipedia.org/wiki/Imperial_Japanese_Navy_submarines) The Japanese did not “name” the subs like they named their (major) surface warships (“Soryu”, or “Blue/green dragon”). The “I” spanned many types and classes of subs. The Germans did not name their subs either, just numbered them (U-101). [List of U-boats of Germany - Wikipedia](http://en.wikipedia.org/wiki/List_of_German_submarines) The US had numbered their boats before & during the First World War (for example, the “S” class boats), but during the interwar period they changed to a naming scheme (“fish” names). > **[List of submarines of the United States Navy](https://en.wikipedia.org/wiki/List_of_submarines_of_the_United_States_Navy)** > > This is a list of submarines of the United States Navy, listed by hull number and by name. > Museum ships The UK also used both schemes over the course of their submarine history. [List of submarines of the Royal Navy - Wikipedia](http://en.wikipedia.org/wiki/List_of_submarines_of_the_Royal_Navy) Edit: Us westerners translate the specific kanji(?) character to “I”, but I don’t know what the Japanese call the character… or if it holds the equivelant phonetic use in Japanese… sorry. ---
**Author:** ![Giles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/giles/32/60_2.png) [@Giles](https://boards.straightdope.com/u/Giles)\ **Post date:** [November 23, 2010, 5:12pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/3 "2010-11-23T17:12:50Z")
> [@mlees](#): > > Edit: Us westerners translate the specific kanji(?) character to “I”, but I don’t know what the Japanese call the character… or if it holds the equivelant phonetic use in Japanese… sorry. Is it 伊 ? According to the [Wiktionary](http://en.wiktionary.org/wiki/%E4%BC%8A), the On reading in Japanese is “i”. ---
**Author:** ![mlees](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@mlees](https://boards.straightdope.com/u/mlees)\ **Post date:** [November 23, 2010, 5:22pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/4 "2010-11-23T17:22:00Z")
> [@Giles](#): > > Is it 伊 ? According to the [Wiktionary](http://en.wiktionary.org/wiki/%E4%BC%8A), the On reading in Japanese is “i”. In these photos, it looks like a “1” or a “T” painted on the conning tower. > **[File:I-26 Japanese submarine.jpg](https://en.wikipedia.org/wiki/File:I-25.jpg)** > > العربية ∙ čeština ∙ Deutsch ∙ English ∙ español ∙ français ∙ italiano ∙ 日本語 ∙ 한국어 ∙ македонски ∙ Bahasa Melayu ∙ português ∙ русский ∙ sicilianu ∙ Tiếng Việt ∙ 中文 ∙ 中文（简体） ∙ 中文（繁體） ∙ +/− > Click on a date/time to view the file as it appeared at that time. > You cannot overwrite this file. The following 4 pages use this file: > **[File:I-58.jpg](https://en.wikipedia.org/wiki/File:I-58.jpg)** > > 伊号第五十八潜水艦 (I-58 submarine), Japanese submarine, after conversion 1945 > العربية ∙ čeština ∙ Deutsch ∙ English ∙ español ∙ français ∙ italiano ∙ 日本語 ∙ 한국어 ∙ македонски ∙ Bahasa Melayu ∙ português ∙ русский ∙ sicilianu ∙ Tiếng Việt ∙ 中文 ∙ 中文（简体） ∙ 中文（繁體） ∙ +/− > Click on a date/time to view the file as it appeared at that time. > You cannot overwrite this file. > **[File:I400 2.jpg](https://en.wikipedia.org/wiki/File:I400_2.jpg)** > > Japanese submarine I-401. Source archive copy at the Wayback Machine > العربية ∙ čeština ∙ Deutsch ∙ English ∙ español ∙ français ∙ italiano ∙ 日本語 ∙ 한국어 ∙ македонски ∙ Bahasa Melayu ∙ português ∙ русский ∙ sicilianu ∙ Tiếng Việt ∙ 中文 ∙ 中文（简体） ∙ 中文（繁體） ∙ +/− > Click on a date/time to view the file as it appeared at that time. > You cannot overwrite this file. > **[File:I-52.jpg](https://en.wikipedia.org/wiki/File:I-52.jpg)** > > العربية ∙ čeština ∙ Deutsch ∙ English ∙ español ∙ français ∙ italiano ∙ 日本語 ∙ 한국어 ∙ македонски ∙ Bahasa Melayu ∙ português ∙ русский ∙ sicilianu ∙ Tiếng Việt ∙ 中文 ∙ 中文（简体） ∙ 中文（繁體） ∙ +/− > Click on a date/time to view the file as it appeared at that time. > You cannot overwrite this file. The following page uses this file: ---
**Author:** ![Giles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/giles/32/60_2.png) [@Giles](https://boards.straightdope.com/u/Giles)\ **Post date:** [November 23, 2010, 5:40pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/5 "2010-11-23T17:40:13Z")
> [@mlees](#): > > In these photos, it looks like a “1” or a “T” painted on the conning tower. That’s the [katakana イ](http://en.wiktionary.org/wiki/%E3%82%A4), derived from the kanji 伊, and pronounced “i”. ---
**Author:** ![mlees](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@mlees](https://boards.straightdope.com/u/mlees)\ **Post date:** [November 23, 2010, 5:50pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/6 "2010-11-23T17:50:12Z")
> [@Giles](#): > > That’s the [katakana イ](http://en.wiktionary.org/wiki/%E3%82%A4), derived from the kanji 伊, and pronounced “i”. Thanks! Is the “i” as in “kite”, or “sheet”? ---
**Author:** ![Giles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/giles/32/60_2.png) [@Giles](https://boards.straightdope.com/u/Giles)\ **Post date:** [November 23, 2010, 5:52pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/7 "2010-11-23T17:52:27Z")
> [@mlees](#): > > Thanks! > > Is the “i” as in “kite”, or “sheet”? More like “sheet” or “hit”. ---
**Author:** ![wellanuff](https://avatars.discourse-cdn.com/v4/letter/w/57b2e6/32.png) [@wellanuff](https://boards.straightdope.com/u/wellanuff)\ **Post date:** [November 23, 2010, 5:59pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/8 "2010-11-23T17:59:02Z")
It is " 伊", but on the hull they would paint the katakana character “イ” which reflects the pronunciation of " 伊". Since there were other types of submersible craft using “RO” (呂) and ”HA” (波) as part of their nomenclature, it is clear that these designations were chosen on the basis of the old Japanese “alphabet” (which was a poem that contained all of the syllabary), since I-RO-HA are the first three syllables of the poem. So basically, it is an old Japanese version of A, as in ABC. Regarding Midway, since the Japanese were not unfamiliar with letters (and since there is no kana that corresponds to “F”), I would imagine that they simply used random pairs of letters as a coded designation. Here is an extra tidbit on Japanese nomenclature: You may have noticed that the names of specific aircraft models and tank models may sometimes include the term “Type 97,” “Type 98”, etc. The number is derived from the last two digits of the Japanese imperial year, numbered from 660 BC. Therefore, “Type 98” entered service in 2598 (1938), etc. I have always been glad that the last digit of the Western calendar and the imperial calendar were identical; it makes conversion easy. This means that 1940 was the year 2600 under the imperial calendar. So now you can see where a famous Japanese fighter aircraft got its name, if you didn’t happen to know already. ---
**Author:** ![JerseyMarine2092](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@JerseyMarine2092](https://boards.straightdope.com/u/JerseyMarine2092)\ **Post date:** [November 23, 2010, 7:07pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/9 "2010-11-23T19:07:58Z")
I have a question from an observation I’ve made from the designation of IJN aircraft. The Japanese system seems to follow the same letter-number-letter system that was used by the USN in the same time period. Is this something that was adopted by Western Intelligence and then became widespread, or did the Japanese use the same system. ---
**Author:** ![mlees](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@mlees](https://boards.straightdope.com/u/mlees)\ **Post date:** [November 23, 2010, 7:36pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/10 "2010-11-23T19:36:14Z")
> [@JerseyMarine2092](#): > > I have a question from an observation I’ve made from the designation of IJN aircraft. The Japanese system seems to follow the same letter-number-letter system that was used by the USN in the same time period. Is this something that was adopted by Western Intelligence and then became widespread, or did the Japanese use the same system. > **[Imperial Japanese Navy Air Service](https://en.wikipedia.org/wiki/Imperial_Japanese_Navy_Air_Service#Naval_Aircraft_identification_System)** > > The Imperial Japanese Navy Air Service (大日本帝國海軍航空隊, Dai-Nippon Teikoku Kaigun Kōkū-tai) (IJNAS) was the air arm of the Imperial Japanese Navy (IJN). The organization was responsible for the operation of naval aircraft and the conduct of aerial warfare in the Pacific War. > The Japanese military acquired its first aircraft in 1910 and followed the development of air combat during World War I with great interest. Japan initially built European aircraft under license, but by the early 1930s Japanes... The Japanese General Naval Staff (the Admirals and other high muckety-mucks) were trained in western style academies ( [Imperial Japanese Naval Academy - Wikipedia](http://en.wikipedia.org/wiki/Imperial_Japanese_Naval_Academy) ). When Japan decided to modernise, they decided to learn and emulate the methods of the strongest European powers. (Great Britain (Navy), France & Prussia (Army).) It’s not surprising that they planned and organised their militaries with similar meticulus methods. 🙂 ---
**Author:** ![JerseyMarine2092](https://avatars.discourse-cdn.com/v4/letter/j/8491ac/32.png) [@JerseyMarine2092](https://boards.straightdope.com/u/JerseyMarine2092)\ **Post date:** [November 23, 2010, 8:11pm UTC](https://boards.straightdope.com/t/explain-these-wwii-japanese-naming-conventions-please/561663/11 "2010-11-23T20:11:29Z")
> [@mlees](#): > > [Imperial Japanese Navy Air Service - Wikipedia](http://en.wikipedia.org/wiki/Imperial_Japanese_Navy_Air_Service#Naval_Aircraft_identification_System) > > The Japanese General Naval Staff (the Admirals and other high muckety-mucks) were trained in western style academies ( [Imperial Japanese Naval Academy - Wikipedia](http://en.wikipedia.org/wiki/Imperial_Japanese_Naval_Academy) ). > > When Japan decided to modernise, they decided to learn and emulate the methods of the strongest European powers. (Great Britain (Navy), France & Prussia (Army).) > > It’s not surprising that they planned and organised their militaries with similar meticulus methods. 🙂 Thanks. Being fairly familiar with the IJN I had a hunch that was the case, but I could never find any confirmation.