Tokusetsu Kansen Butairei, bobitai and keibitai

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Tokusetsu Kansen Butairei, bobitai and keibitai

#1

Post by hisashi » 01 Aug 2015, 15:55

1.Tokusetsu Kansen Butairei(特設艦船部隊令 16 Apr 1919)
Correction: firstly this decree was issued in 23 Dec 1916. Sorry for having quoted updated date.

In Sino-Japanese War, IJN requisitioned a merchant ship Seikyo-Maru and set up some guns on her. Navy Chief-in-Staff Kabayama Sukenori wanted to see the decisive battle on his own eyes and he went to the Battle of the Yalu River (1894) on her, where he barely escaped from death in such a weak ship. Anyway, IJN restored and returned Seikyu-Maru and she became a favorite ship in Shanghai route.
https://en.wikipedia.org/wiki/Sei-Kyo_Maru

Seikyo-Maru was called in various category name. Junyokan Daiyo (proxy cruiser), Tokumukan or Tokusetsu kantei in more or less official documents. As IJN grew up, they made effort to sort out notions on Tokusetsu ships and Tokumu ships.

Tokusetsu Kansen Butairei(16 Apr 1919) defined Tokusetsu Kansen [and] Butai as 'ships and units deployed on wartime, incidents or in needs' and noted that 'are normally to be fulfilled by requisitioned ships'.

This decree named three large categories in Tokusetsu Kansen.

(1) Tokusetsu Gunkan
Auxiliary cruisers, aircraft carriers and other combat ships, converted from merchant ships and returned after restoration.
For example CVL Kasuga-maru was a tokusetsu aircraft carrier. In Aug 1942 the navy bought her from Nippon Yusen Co. and reclassified her as an aircraft carrier, with new name Taiyo. CVL Junyo was bought by the navy in Feb 1941 on the dock, but on some reason finished in May 1942 as a Tokusetsu aircraft carrier Junyo (not Kashihara-Maru as construction started). It was July 1942, after Aleutian campaign ended, that she moved to (line) aircraft carrier.

(2) Tokusetsu Tokumutei

Converted smaller ships and boats, lightly or not armed against surface vessels. Anti-sub patrol ,minesweeping etc. were their tasks.
Tokumu was another vague word, explained in the next.

(3) Tokusetsu Tokumu Kansen

For example, IJN had some fleet oiler; Shiretoko-class, Ondo-class etc. They were in large category of Tokumukan. Non-combat mission ships are naturally tokumukan. But in missions related to mines and submarines, the border of 'non-combat mission' was vague, and was not always straight.
Converted freighter/oilers, maintenance ships etc. belonged to the category of Tokusetsu Tokumu Kansen. Converted tender ships for smaller ships or submarines were classified in (1).


In companion IJN issued another decree, Tokusetsu Kansen Butai Teiinrei. Teiin was an authorized personnels' rank, specialities and respective numbers. Along with Tokusetsu Kansen, all wartime standalone unit was listed, and in each amendment (especially creation and abolition of unit) IJN issued a decree of change. So seeing it and related decree on teiin, we can sort out many confusions in keibitai, bobitai and similar units.

(to be continued)

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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#2

Post by hisashi » 02 Aug 2015, 08:22

2.Bobitai and related formations

2.1 bobitai in major navy bases

In 1889 IJN firstly issued a decree to form a minesweeper unit in navy ports. It was one of origin to Bobitai.

On 17 Dec 1914, French submarine Curie raided Austria-Hungary naval base at Pola. By chance I know of this unsuccessful attack owing to captured Curie's new skipper, Georg von Trapp. Anyway, IJN had a good reason to worry about raid by submarine to their base, even before HMS Royal Oak was sunk.
https://en.wikipedia.org/wiki/SM_U-14_(Austria-Hungary)

Bobitai in each Chinjufu was an indispensable, and an oldest part of base force. In permanent IJN base they always had a bobitai. As coastal artillery was passed to the army, bobitai took on watch, patrol (by lightly armed ships/boats) and some gatekeeper duty.

Some bobitai was to be formed only in hostility/tention. For example, to watch three straits to Setonaikai, Kure Chinjufu was to raise Kii, Shimonoseki and Saeki bobitai in needs.

Bobi sentai was raised in 16 Dec 1934 for Yokosuka, Kure and Sasebo, just after IJN had their first anti-sub boat. Authorized strength of the HQ was only 18 men; it was a HQ unit for unified direction of small ships on base defense.

Similarly in 11 Dec 1933 IJN issued a decree to form Keibi Sentai in navy bases. They were also a small HQ (18 men) to direct ships for the security of each navy districts, respectively large area. Its image might be 'commerse protection at sealane'. Though bobitai reports to their Bobi Sentai (if they had), it was up to the commander of Chinjufu which ship was at disposal of which sentai. Keibi Sentai was disbanded just after the Pacific War began and many of converted ships earmarked for keibi sentai worked as watchers in ocean.

2.2 Tokusetsu bobitai

In Russo-Japanese War, Japan occupied Russian Concession in Masan city, facing Chinkai(Jinhae) Bay. IJN built facilities mainly in Geojedo Island and placed bobitai there. Until Chinkai was upgraded to navy port, a few special decree authorized their formation.

In 1916, when Tokusetsu Kansen Butairei went into effect, they included a general rule for makeshift bobitai, 'tokusetsu bobitai'. It was a category name and each bobitai was simply distinguished by number or location name.

In 31 Jul 1941 IJN introduced new scheme 'tokusetsu keibitai' and six keibitai appeared in the first authorized strength chart;九江(KYUKIANG), Nanjing,Shuzan-To Islands (Zhōushān Islands, 舟山島), 15th, 16th and 81st. But on the same day 15th and 16th bobitai were abolished. Apparently the two was 'renamed'.

They were serving in Hainan Island with the army, and took on the defense of Hainan after army units went back to China theater. Navy bureaucrat might feel they must take on the occupation of lands of no value as the navy base, so the unit should have new name.

In the course of war tokusetsu bobitai did not increase much, while so many tokusetsu keibitai were raised.

(to be continued)


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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#3

Post by Wellgunde » 02 Aug 2015, 12:49

Thank you, Hisashi. This is a very helpful series and I am looking forward to further installments.
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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#4

Post by hisashi » 02 Aug 2015, 14:44

3.Tokusetsu Base Force and Special Base Force

Base Force and Special Base Force are really mysterious in their difference.

Decree on navy special base force (海軍特別根拠地隊令, 19 Oct 1939) was far after tokusetsu base force was added to Tokusetsu Kansen Butairei in 19 Jul 1920. What we know as base force was tokusetsu base force in category.

Only HQ of BF was included in Tokusetsu Kansen Butai Teiinrei, 43 men. Amended article 49 part 2 of Tokusetsu Kansen Butairei 30 Oct 1924 reads 'tokusetsu base force shall be formed with two or nore tokusetsu bobitai'. Perhaps by the end of war this article was rewritten again to allow various combat formations of similar size, but it was clear that BF was intended as a HQ unit to direct two or more combat formations (and non-combat formations if any).

On the other hand, Decree on navy special base force showed two type of standard authorized strength chart, respectively 1350 and 1070 men (officer to sailor). SBF had infantry of their own, while BF HQ did not. Especially in the first phase of the Pacific War, BF HQ under respective fleet served as an intermediate HQ to deal with various ground formations in occupied area. In addition to it, typically BF HQ had small ships and boat units, which became scarcer and scarcer near the end of war.

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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#5

Post by hisashi » 03 Aug 2015, 16:44

4 SNLF

4.1 Shanghai and Kanko(Hankou) until 1932

In 1911, Wuchang Uprising happened preceding Xinhai Revolution, in Wuchang city next to Kanko.
https://en.wikipedia.org/wiki/Wuchang_Uprising
https://en.wikipedia.org/wiki/Xinhai_Revolution

Kanko had concessions of many countries, including the U.S., U.K. and Japan. Consuls agreed to make up self-protection force from gunboats stationed in Yantze River. This small unit, at first 70 men from protected cruiser Tsushima, was originally for the protection of concession in Kanko and Shanghai.
https://en.wikipedia.org/wiki/Japanese_cruiser_Tsushima

At first they did not have formal unit name. In a generic word they were called as Shanghai (Kanko) Rikusentai. In 1932, according to a secret report of Shanghai Incident (JACAR C14120078200), Shanghai Rikusentai in 1932 had 43 officers+WO, 93 PO and 563 sailors. They were divided into two battalion, but a few platoon directly reported to each battalion.

4.2 SNLF on decree and Yantze River to the end of war

After the incident, in 1 Oct 1932 IJN issued a decree on SNLF. But in article 2 SNLF was to report to China Expeditionary Fleet. This decree was intended for Shanghai SNLF, and maybe Kanko.

For a while they used the designation Kanko SNLF, but in 1934 they ceased it and instead Kanko force, perhaps 200 or so, as Kanko Hakentai (detachment [from Shanghai SNLF]). In 1937 many web pages argued that IJN evacuated 300 men in Kanko to reinforce Shanghai. Perhaps all rely on one original, but I have not found any reliable source. Anyway, IJN kept company-sized unit in Kanko.

All SNLF we know, except Shanghai SNLF, were raised on Tokusetsu Kansen Butairei, amended in 15 Oct 1936 to authorize tokusetsu chinjufu SNLF.

From Nov 1939 Kanko SBF was raised. In previous year 1938 IJN occupied 九江(Kyuko,Jiujiang) facing Yantze River, for operations in lakes and rivers branching to the south from Kyuko. In Jul 1941 IJN upgraded small Kyuko base into Kyuko keibitai. But after the Pacific War began they were downgraded and/or abolished (Kanko keibitai disbanded in 20 Aug 1943). Their mother unit, 1st China Expeditionary Fleet itself became Yantze River Ward SBF. In the last stage of war, Yantze River Ward SBF controlled remained gunboats, Kyuko keibitai and some ground force of its own to maintain large area on Yantze River, including Kanko.

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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#6

Post by hisashi » 04 Aug 2015, 17:30

5.keibitai

5.1 keibitai in Yokosuka, Maizuru, Kure, Sasebo and (later) Takao

In 17 Nov 1941 IJN ordered to create navy keibitai at Yokosuka, Maizuru, Kure and Sasebo. Later Takao keibitai was added to this list. They were permanent unit, or exactly a part of Chinjufu organization. So authorized personnel chart was not on Tokusetsu Kansen Butai Teiinrei, but on Kaigun Teiinrei, where charts for major warships gathered.

For example Kure keibitai was to have 15 line officers, 6 tokumu officers, 2 WO, 81 PO and 522 sailors.

Their duty was not specified in the order. But according to their wartime log, they took on
(1)Operation of anti-aircraft guns and AAMG (25mm or smaller)
(2)Operation of searchlights and other equipments used with AA gun, including RADAR
(3)Gatekeeper/centry duty with rifles in navy facility
(4)potential task as navy infantry, such as fire-fighting
Most of keibitai men concentrated in chinjufu, so some of RADAR were under the control of bobitai in distant location. on the contrary, some keibitai men operated large caribre AA gun to defend bobitai facility.

In Dec 1944 Kure keibitai had 6516 sailors+PO. It was partly because they shared the burden of novice training for AA gunners.

5.2 tokusetsu keibitai and the differences among them, bobitai and SNLF

In 31 Jul 1941, before chinjufu keibitai was authorized but quite just before IJN began the Pacific War, tokusetsu keibitai was added to Tokusetsu Kansen Butairei.

The mission of bobitai and keibitai in this decree were quite similar. But because bobitai was originally a guard of port, bobitai was responsible for security in neighboring sea area. In effect they seldom had battle-worthy ships so the responsibility of security was no more than patrol/watch, but keibitai was entirely free from any responsibility at sea, though they often had transport/communication boats.

And no mission for tokusetsu SNLF was specified, while Shanghai SNLF was to share fleet's responsibility of guarding [Japanese residents etc.]. I guess tokusetsu SNLF was intended for what keibitai was not - offence. Basically the two was similar unit, so SNLF was often renamed to keibitai after landing had ended and security mission began.


[end of article]

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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#7

Post by Wellgunde » 05 Aug 2015, 13:18

Do the authorizing documents list the assignment and numbers of personnel within the particular unit? For example, Administration: 4 officers, 10 petty officers.
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Re: Tokusetsu Kansen Butairei, bobitai and keibitai

#8

Post by hisashi » 05 Aug 2015, 18:01

All lists are in total, though their specialty was to some extent specified. For example, medical officer, mechanics officers were counted aside from line officers. But sailors' specialty had not been specified as they faced the scarcity of long-trained personnel.

p.s. Authorized personnel chart was NOT order of battle. The chart specify how many senior officers post and/or buntaicho post were allotted. To some extent the leader/skipper/commander could increase/decrease men in each buntai. Then buntai leaders organized their men as they liked. In an extreme case, a SNLF had two company but no company leader was named, perhaps because they were in short of officer. In effect each platoon leader reported to their 'ground combat buntai' leader and company worked merely as the name of area. Even in wartime log, they did not report their precise order of battle.

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