Japanese Submarine JS Chōgei Commissioned March 10, 2026

The Taigei-class submarine JS Chōgei "Long Whale" (see it in table below) was commissioned on March 10, 2026.

Japan uses a continuous build (1 new submarine per year) system. New classes (the Taigeis are the latest) are created every 10 years or so. 

Submarine production is shared between Kawasaki Heavy Industries (KHI) and Mitsubishi Heavy Industries (MHI) each building sections amounting a half hull equivalent each, each year. The hull sections are placed on rafts, then towed between the KHI and MHI shipyards. Both shipyards are at the Port of Kobe. 

There are gradual improvements (often in propulsion, snorkel, sensor and weapon systems) within Japanese submarine classes and between classes.

Also see SubMatt's Updated History & Photos of Japanese Submarines After WWII of January 17, 2015 at https://gentleseas.blogspot.com/2015/01/history-of-japanese-submarine-after-wwii.html It contains a vast amount of Japanese originated information on Japanese submarines. From the end of WWII (September 2, 1945) to June 30, 1960 Japan had no operational submarines. 

From December 1957 Japan restarted submarine production based on US experience (eg the US Gato class) and based on long institutional experience building advanced submarines for the former WWII Imperial Japanese Navy.

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TABLE

This Table is unique to Submarine Matters mainly created by "S"/Anonymous and Pete.

Japan's Diesel-Electric Classes of Submarine (SSKs)

The 2nd Oyashio class, Soryus & Taigeis as at March 13, 2026. 

SS No. Diesel Type Motor	Build No Name	Pennant No.	Ministry of Finance (MoF) approved Ministry of Defense Budget in Billions of Yen (¥B)	LABs + AIP: or LIBs	Laid Down	Laun -ched	Comm ission ed	Built By
5SS + 6SS now training Oyashios 2 Toshiba motors	8105 + 8106 Oya shio means currents	SS-590/ now TSS3608, SS-591 now TSS3609	¥52.2B FY1993 2 x 12V25/25S  diesels for all Oyashio class (each diesel 2,000kW)	LABs only	1994 & 1995	1996 & 1997	1998 & 1999 Converted to training subs on 2015 + 2017	Built at KHI
7SS-15SS 8 active Oyashios  10 subs 2 Toshiba motors SMC-7?	8107 -8115 various	SS-591-600	¥52.2B per sub FY1994-FY2003	LABs only	15SS Feb 2004	15SS Nov 2006	15SS Mar 2008	MHI & KHI
16SS 12 Active Soryus/ Dragon class  Mk I Collided with Ocean Artemis Feb 8, 2021	8116 Sōryū means dragon 2,900 tonnes surf- aced	SS-501	¥60B FY2004  Mk.1 LAB+AIP Soryus have 2 x Kawasaki  12V25/25SB  diesels (totaling 4,240kW) + 4 x 4V-275R Mk.III AIP + a SMC-8 motor	LABs + AIP	Mar 2005	Dec 2007	Mar 2009	Built at MHI Home Port Kure
17SS	8117 Unryū	SS-502	¥58.7B FY2005	LABs + AIP	Mar 2006	Oct 2008	Mar 2010	KHI Kure
18SS	8118 Hakuryū	SS-503	¥56.2 FY2006	LABs + AIP	Feb 2007	Oct 2009	Mar 2011	MHI Kure
19SS	8119 Kenryū	SS-504	¥53B FY2007	LABs + AIP	Mar 2008	Nov 2010	Mar 2012	KHI Kure
20SS	8120 Zuiryū	SS-505	¥51B FY2008	LABs + AIP	Mar 2009	Oct 2011	Mar 2013	MHI Yokosuka
21SS LIBs Concept Research Project			No 21SS built. It was an 8 year research project on LIBs. 1st LIBs sub launched was 27SS in 2018.
22SS	8121 Kokuryū	SS-506	¥52.8B FY2010	LABs + AIP	Jan 2011	Oct 2013	Mar 2015	KHI Yokosuka
23SS	8122 Jinryu	SS-507	¥54.6B FY2011	LABs + AIP	Feb 2012	Oct 2014	7 Mar 2016	MHI Kure
24SS	8123 Sekiryū	SS-508	¥54.7B FY2012	LABs + AIP	15 Mar 2013	2 Nov 2015	13 Mar 2017	KHI Kure
25SS	8124 Seiryū	SS-509	¥53.1B FY2013	LABs + AIP	22 Oct 2013	12 Oct   2016	12 Mar 2018	MHI Yokosuka
26SS	8125 Shoryū	SS-510	¥51.7B FY2014 last SMC-8 motor	LABs + AIP	2014	6 Nov 2017	18 Mar 2019	KHI Kure
27SS a Soryu "Mk II" as it has LIBs. 1st Soryu Mk II	8126 Oryū 11th Soryu	SS-511	¥64.4B FY2015  with 2 12V25/25SB diesels (totaling 4,240kW)  SMC-8B motor [Wispy+Anon agree it has 640 LIB/SLH modules], other improvements	LIBs only (SLH type)	Nov 2015	4 Oct 2018	5 Mar 2020	MHI Kure
28SS Soryu Mk II, 12th & final Soryu	8127 Toryu	SS-512	¥63.6B FY2016 "2,950t" surfaced 2 12V25/25SB  diesels.	NCA? LIBs	Jan 2017	6 Nov  2019	24 Mar 2021	KHI Yokosuka
29SS 1st Taigei Class means Whale 3,000 tonne (surfaced)	8128 Taigei "Big  whale" Used as test sub. Not opera- tional	SS-513	¥76B FY2017 (Heisei 29) Higher ¥76B budget  may be due to 1st of class many changes.  2 x 12V25/25SB diesels or variants (totaling 4,240kW). [Wispy  says 640 LIB/SLH modules, Anon says 720.]	SLH LIBs maybe 960	16 Mar 2018	14 Oct 2020	9 Mar 2022	MHI Home Port Yokosuka
30SS  2nd Taigei Class  whale a mythol- ogical creature	8129 Hakugei "White whale" First opera- tional Taigei	SS-514	¥71.5B FY2018  (Heisei 30) 12V25/25SB diesels or variants (totaling 4,240kW) , [Wispy  says 640 LIB/SLH modules, Anon says 720.]	SLH LIBs	25 Jan 2019	14 Oct 2021	20 Mar 2023	KHI Home Port Kure
Reiwa Era 01SS  3rd Taigei Class	8130 Jingei "Swift whale"	SS-515	¥70B FY2019 (Reiwa 01) 12V25/25SB diesels or variants (total 4,240kW)	SLH LIBs maybe 960+	24 Apr 2020	12 Oct 2022	8 Mar 2024	MHI
02SS  4th Taigei Class	8131 Raigei Thunder whale	SS-516	¥B70.2B FY2020 (Reiwa 02) Improved SLH LIBS. New 2 x 12V25/31S diesels (totaling 5,520kW) & see	Improved  SLH LIBs	26 Mar 2021	17 Oct 2023	6 Mar  2025	KHI
03SS 5th Taigei Class	8132 Chogei "Long Whale"	SS-517	¥B68.4 FY2021 also see Kosuke Takahashi at  Naval News	LIBs	19 Apr 2022	4 Oct 2024   also	10 Mar 2026	MHI
04SS 6th Taigei Class	8133 Sōgei Blue Whale	SS-518	¥B73.6B FY2022	LIBs	28 Mar 2023	14 Oct 2025	Mar?  2027	KHI
05SS  7th Taigei Class	8134	SS-519	¥80.8B FY2023	LIBs	17 Apr 2024	2026	? Mar 2028	MHI
06SS 8th Taigei Class	8135	SS-520	¥95.0B FY2024 page 23	LIBs	19 Dec 2024	2027	2029	KHI
07SS  9th Taigei Class	8136	SS-521	¥B116.1 FY2024  for 9th Taigei page 23 [1]	LIBs	2026	2028	2030	MHI
08SS  10th Taigei Class	8137	SS-522	¥B120.8 "for 10th Taigei... for enhanced detection capabilities & manpower saving systems for effective intelligence & surveillance activities" page 27 [2]	LIBs	2027	2029	2031	KHI

Key to Table: Table information provided by S = Anonymous to Submarine Matters. LABs = lead-acid batteries, AIP = air independent propulsion, LIBs = Lithium-ion Batteries. 
¥***B = Billion Yen. MHI = Mitsubishi Heavy Industries, KHI = Kawasaki Shipbuilding Corporation of Kawasaki Heavy Industries. 

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[1] Japanese “Ministry of Defense: Progress and Budget in Fundamental Reinforcement of Defense Capabilities: Overview of the FY2025 Budget” page 23 

[2] Japanese “Ministry of Defense: Progress and Budget in Fundamental Reinforcement of Defense Capabilities: Overview of the FY2026 Budget” page 27

An Australian Wedgetail Aircraft & Missiles to Defend UAE

Announced today Australia is sending an E-7A Wedgetail early warning and control aircraft to the UAE by Friday 13th March 2026. A Wedgetail is based on a 737 platform, has a large radar and specialised crew of about 14 crew per watch/mission. The Wedgetail's radar is particularly useful for spotting low flying Iranian drones and cruise missiles. In all about 85 RAAF personnel are going to the UAE.

Australia has around 100 tri-service Australian Defence Force personnel at Joint Task Force 633 with vague "command and control" functions at Al Minhad Air Base. The base remains operational despite being targeted by an Iranian drone strike on March 1, 2026. Australia’s air force also uses Qatar’s Al Udeid Air Base, alongside the UK and US.  

The Wedgetail activity is integrated with the second aspect of Australia's assistance to the UAE which is probably initially sending around 100 AIM-120 Advanced Medium-Range Air-to-Air Missiles (AMRAAM). These will likely be air-freighted with their heavy radar and coordination components to the UAE by RAAF C-17 cargo aircraft. With an average system cost to Australia of perhaps A$4.5 million each, the AMRAAMs may be launched by jets of the UAE. Also some AMRAAMs will be in ground launched NASAMS batteries. 

For defence of Australia the RAAF appears to have budgeted for 400-535 AMRAAMs, for Australia's own defence,, tops. These limited stocks may be vey uneconomic if tasked to shoot down much cheaper Iranian drones and cruise missiles fired at the UAE over a very short period. Iran is firing 10s of missiles and 100s of drones over the Middle East daily. 

Unfortunately AMRAAMs may currently have difficulty shooting down expensive Iranian ballistic missiles. Maybe US Patriots and other ABMs will do/are doing those jobs. 

USS Charlotte (SSN-766) Torpedoed Iranian Frigate IRIS Dena

Video here and above courtesy Warships & Warriors, uploaded March 5, 2026.
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On March 5, 2026 it was reported the torpedo that struck an Iranian frigate, IRIS Dena, was fired by USS Charlotte (SSN-766) a Los Angeles-class attack submarine, multiple US officials told CBS News on March 5. USS Charlotte reportedly fired two MK 48 torpedoes at IRIS Dena, the officials said. The first one missed, but the second one sank the Dena. This was in the Indian Ocean just south of Sri Lanka. 

Sri Lankan sailors rescued 32 Iranian sailors from the commissioned in 2021 Moudge class frigate IRIS Dena. 104 Iranian sailors were killed. This is the first known attack by an American submarine on a surface warship since WW2. 

Previous ships sunk by submarine's torpedoes since 1945 were an Indian frigate, INS Khukri, sunk by Pakistani conventional sub PNS Hangor in 1971; Argentine Navy cruiser General Belgrano sunk by HMS Conqueror SSN in 1982; and South Korean corvette ROKS Cheonan sunk in March 2010, most likely by a torpedo from a North Korean small sub. 

US Secretary of War Pete Hegseth (in his ignorance of Argentinian, Indian and South Korean sinkings) said at a press conference this morning. “Instead, sunk by a torpedo, quiet death [but big explosion!], the first sinking of an enemy ship by a torpedo since World War II.” Ultranationalist Hegseth may feel non-US history doesn't exist.

While Israel may accurately see Iran as a mortal enemy, for the US this is an elective war. It is boosting oil prices for US oil companies and for America's oil rich allies. Iranian missiles and drones endanger those Mid-East allies. It can also be seen as an attempt by Trump to push the "rally around the President during time of war" effect. This is in the runup to the US Midterm Elections on November 3, 2026. US citizen's sorrow over US war dead and oil price rises may have the opposite effect on Trump's political herpes.