Third Taigei-Class Submarine JS Jingei Launched

 

SS515 Jingei Launched in MHI's Kobe shipyard

The Japan Maritime Self Defense Force ( JMSDF ) had launched its third Taigei-class submarine on 12 Oct 2022 at Mitsubishi Heavy Industries' Kobe shipyard. It was named the Jingei, meaning swift whale. This came almost one year since the launch of the second-in-class the Hakugei which means white whale.

The Taigei-class submarines are advanced designs with lithium-ion batteries instead of the tried and proven lead-acid batteries. In Japanese, taigei means " big whale ". It is now almost certain that the entire class will be named after whales.

This will be the second Japanese naval vessel to bear the name Jingei, the first being the Imperial Japanese Navy ( IJN ) submarine tender which was launched in 1922 and saw service in World War Two. In kanji ( Chinese characters ), Jingei would be written as 迅鯨. In hiragana it would be じんげい.

Since the IJN warships always had their names in kanji, in order to distinguish their modern warships from those of the IJN's WWII vessels, JMSDF deliberately avoids expressing the ship's name in kanji and officially uses the hiragana form instead.

According to the JMSDF ship naming convention, submarines would be named after maritime phenomenon, marine animals and auspicious creatures. The name jingei conjures a majestic whale, King of the Ocean, streaking through the waves at breakneck speeds ...

The Jingei will be commissioned around March 2024.

The Jingei is the 1330th ship built by the MHI Kobe shipyard. JMSDF

The Jingei all dressed up for the launch and naming ceremony. JMSDF

I name thee ... Jingei. JMSDF

SS515 Jingei ( じんげい ) name revealed. JMSDF

View from VIP stand with naming documents. JMSDF

Cord cutting with sacred ship launching silver axe followed. JMSDF

Sacred silver axe for launching the JS Jingei. JMSDF

The Jingei is launched. JMSDF

Ribbons flutter amidst the lively tune of the Gunkan March. JMSDF

Watch the Video below :

Second In The Pod : Hakugei SS-514 たいげい型潜水艦二番艦はくげい進水

JS Hakugei ( SS-514 ) shortly after launch. Photo : JMSDF

 

Japan's second Taigei-class lithium-powered attack submarine has been launched at the Kawasaki Heavy Industries Kobe Shipyard this afternoon.  This came exactly a year after the launch of the Taigei. It has been named the Hakugei ( はくげい ) which literally translated means white whale. In kanji characters Hakugei would be written as 白鯨. 

JMSDF twitted that the name Hakugei refers to the white sperm whale ( マッコウクジラ makkokujira 抹香鯨 ). The ship naming and launching event was officiated by Rear Admiral Sonoda Naoki ( 園田直紀 ), Commander Kure District.

Official JMSDF video on the naming and launching ceremony of the Hakugei here :

Hakugei at Kawasaki Kobe Shipyard. Photo : JMSDF

RAdm Sonoda Naoki with silver ship launching axe.
Photo : JMSDF

The submarine is officially named by Minister for Defense
Kishi Nobuo ( 防衛大臣 岸信夫 ). Photo JMSDF

Hakugei going down the slipway. Photo : JMSDF

Hakugei SS-514 shortly after launch at KHI Kobe Shipyard. Photo : Wikipedia

                                                                                Video : Kobe Keizai News

The naval band played the theme song of Space Battleship Yamato at the beginning of the video ....

SSK Soryu's Collision Off Cape Ashizuri : Curse of the Kuroshio?

 

The damaged SSK Soryu at Kochi Port 
9th Feb 2021. Photo : Asahi Shimbun 

Collision At Sea

Collisions at sea involving submarines thankfully do not happen everyday. Even when such unfortunate incidents occur, they tend to take place at remote waters where there are not much media coverage. In any case the need to maintain operational security would ensure very little information whatsoever will be made available to the public on these mishaps.

On 8th Feb 2021, the Japanese attack submarine JS Soryu collided with the Hong Kong registered bulk carrier the Ocean Artemis while it was surfacing during a training deployment in international waters southeast of Cape Ashizuri, Kochi Prefecture. The collision occurred at periscope depth and left the Soryu with extensive damage but fortunately no fatalities.

What was unusual about this incident was the large amount of high resolution images and video footage taken of the damaged submarine after the accident. Once the word was out the Japanese news media even had reporters and cameramen flown out to sea in helicopters to film the stricken submarine, made possible also because of the accident location's proximity to land.

Many theories had been proposed by new agencies and defense web portals as to how and why the accident happened, from poorly trained sonar technicians to equipment failure to thermal layers and even professional negligence. Frequently the opinions of serving or ex-submariners were sought and while they provide a good overview of the matter, none mentioned anything about a local maritime phenomenon that could have played a significant role in causing this incident : the fast moving warm Kuroshio Current that flows northward and eastward off the Pacific coast of Japan.

The Kuroshio Current off the coast of Japan
Here for real time map by earth.nullschool.net

Cape Ashizuri, approximate collision site
and current path of the Kuroshio in red.

The Submarine Soryu

The Soryu is one of the largest and most advanced diesel attack submarine in the world. It is equipped with an air-independent propulsion system. It is also relatively new, being launched as the first-in-class in Dec 2007 and commissioned in March 2009. It has a length of 84m with a displacement of 2900 tonnes surfaced. Its sonar suite comprises of a bow array, flank arrays and a towed array. 

It could make 13 knots on the surface and 20 knots submerged. Its maximum diving depth, though classified, is believed to be between 600m to 800m.

The Soryu is assigned to the 5th Submarine Squadron, 1st Submarine Flotilla operating out of Kure. Her commanding officer is Commander Koji Keisuke ( 恒次啓介 ). The submarine had recently spent considerable time in the ship yard on routine maintenance. She left her home port on 6th Feb 2021 with 90 crew members on a training deployment, most likely for re-certification of her operational readiness.

Soryu-class submarine on surfaced transit.
Photo : JMSDF

The Bulk carrier Ocean Artemis 

The Ocean Artemis is a bulk carrier with a gross tonnage of 51208 tonnes and a dead weight of 93103 tonnes. It was built in 2011. It has an overall length of 229m with a beam of 38m. Its maximum speed is said to be 13.8 knots. It was transporting iron ore from the Chinese port of Qingdao and was heading for the Japanese port of Mizushima, Kurashiki City, Okayama Prefecture when it collided with the Soryu. AIS data suggested that the Ocean Artemis had a draught of 14.9m on the day of the collision.   

Map of Shikoku Island and Kuroshio

The seabed 50km off Shikoku is 
between 1000m to 1500m deep.
Map : Geological Survey of Japan 

Reconstructing The Collision

Based on satellite, oceanographic, meteorological and maritime traffic data, we know that it was a clear but windy day out at sea 50km southeast of Cape Ashizuri on 8th Feb 2021. The wind was gusting at 25 knots from the northwest and whipping up swells with significant wave heights of 1.59m, probably the equivalent of Sea State 4.

The collision site is located over the continental shelf of Shikoku Island and lies over waters about 1000m deep. It straddles not only the main shipping lanes south of Shikoku but also the main path of the warm Kuroshio Current. Despite being winter, the sea surface temperature was about 21C, only dropping to 15C at the 200m depth. The current is strong with a flow speed of about 2 knots and an axis of 070 degrees. 

The Ocean Artemis, laden with ore and riding low in the water, was east bound for the port of Mizushima in the Seto Inland Sea. It would likely be maintaining a course of approximately 060 degrees as she navigates around Shikoku to enter the Inland Sea from the east via the Naruto Straits. 

At 10:58am local time, the Soryu was conducting a surfacing drill when, rising from the deep, she failed to detect the presence of the bulk carrier until she was at periscope depth. It was already too late to take evasive action by the time the surface vessel was seen through the periscope and a collision was inevitable. 

The bow of the bulk carrier struck the starboard side of the submarine's conning tower, denting it and damaging the anechoic tiles covering that area. It also caused severe damage to the starboard hydroplane and the sensor masts, taking out the communications antennae. Three submariners suffered from light injuries like bruises and none required evacuation.

Since the damage occurred mainly on the starboard side of the submarine, it can be deduced that it would have been a glancing blow had the submarine been on a course similar to the bulk carrier or if it were on a reciprocal course. Conversely it would have been a head-on impact had the submarine been maintaining a southerly bearing.

We would later learn that the Ocean Artemis did not report detecting any noise or vibration from the collision and most likely continued with her voyage without even realizing that a collision had taken place.

The loss of communications rendered the Soryu incapable of reporting the incident to the 1st Submarine Flotilla headquarters. Fortunately the Soryu could still move under her own power on the surface and she eventually navigated to an area with cellphone reception. The Ministry of Defense would eventually learn of the accident by 2:20pm. 

Transiting on the surface, the Soryu made it to the port city of Kochi by nightfall. Meanwhile the JCG diverted the Ocean Artemis to Kobe the next day for investigations. There, divers discovered that the impact left multiple scratch marks with black paint residue that presumably matched those from the Soryu on the bulbous bow of the Ocean Artemis. A dent and a 20cm crack corresponding to the point of impact was also found on the bow. This crack had caused some sea water seepage into the vessel.

The black paint residue were collected and had been dispatched to the JCG Research Centre in Tachikawa City, Tokyo, for further analysis and confirmation that they originated from the Soryu.   

Underway enroute to Kochi.
Photo : 5th Regional HQ JCG

Damage to the hydroplane, sensor masts and conning tower 
of the JMSDF submarine Soryu. Photo : Mainichi Shimbun

Moored off Kochi, 9th Feb 2021
Photo : Mainichi Shimbun

Moored off Kochi, 9th Feb 2021
Photo : Mainichi Shimbun

Moored off Kochi, 9th Feb 2021
Photo : Mainichi Shimbun

Moored off Kochi, 9th Feb 2021
Photo : Mainichi Shimbun

The damaged Soryu at Kochi on 9th Feb 2021

Ocean Artemis off Kobe 9th Feb 2021
Photo : Mainichi Shimbun

Divers inspect the bow of the Ocean Artemis
Photo : Asahi Shimbun

Scratch marks on the bow of the Ocean Artemis
Photo : Jiji Press

What Caused The Collision?

Surfacing drills are among the most hazardous submarine operations undertaken during peace time. Even with modern sonar equipment, collisions with surface vessels are always a possibility especially around busy shipping lanes.

Every submarine's forward mounted sonar has blind spots known as the baffles, an area directly behind the submarine where sound detection is not possible. In order to surface safely, a submarine has first to perform a manoeuvre known as clearing the baffles to ensure there are no vessels hiding in the blind spot. It requires the boat to change its course slightly so that the previously hidden areas could now be scanned. Once the baffle is cleared, the submarine will have to execute the ascend to the surface within a specified time of not more than 10 to 15 minutes, any longer and the traffic pattern could have changed.

There is a possibility that the Soryu did not perform a proper baffle clearing or it could have taken too long to ascend after that. Her skipper Cmdr Koji Keisuke had commanded the JS Takashio ( SS-597 ) before assuming command of the Soryu on 15th Oct 2019, so he is not new to his post. However, the Soryu has recently spent considerable yard time on regular maintenance and had just resumed operational training after a long lapse. Perhaps crew proficiency may not be at the peak level and mistakes might be more common.

Clearing the baffle ( sonar blind spot )
Image : Asahi Shimbun

The same trend of thought tells us that the likelihood of the sonar specialists not reporting a surface contact as they should is also possible and could have been made more likely by their long absence from regular training. Having said that, due to the hazardous nature of operating submarines, only the best of the best gets selected to train as submariners, and MSDF personnel have to undergo rigorous training of high standards for their qualification process. So again, professional negligence, though unlikely, cannot be completely ruled out. 

Equipment failure is a remote possibility but Japan's fleet of submarine is young by other navy's standards. Until recently, JMSDF used to retire its submarines after an average of just 20 years! We also know that the Japanese tend to maintain their equipment in tip top condition, and that the Soryu had just completed its regular yard maintenance, so the scenario where there is a catastrophic failure of the sonar system leading to a collision has a low probability. In fact, Chief of the Maritime Staff, Adm Yamamura Hiroshi had already categorically denied any reports of a periscope or sonar malfunction. 

The size and draft of the bulk carrier brings up another possibility to the cause of the accident - the bow-null effect. Simply put, the enormous length of the surface vessel approaching head-on effectively acts as a shield to greatly diminish the acoustic signature from the engine and propellers which are a couple of hundred meters behind the bow. This reduced sound level could have been misinterpreted to be emitted from a source much further away along the same bearing, leading to a potentially disastrous situation. Even veteran submariners have had close shaves due to the bow-null effect. It has also been postulated to be the cause of many collisions between whales and large surface vessels.

Apart from human errors and equipment failures, environmental and geographical factors frequently have a contributory if not causative role to play in such accidents. For submarines, water temperature, depth and to a lesser extend, salinity, will have a huge impact on sound transmission. The existence of shallow thermal layers for example, might create environments with positive sound velocity profile gradients, causing some surface generated sound waves to be deflected upwards. It would result in shadow zones below the layer and make vessel detection from beneath all but impossible. The Kuroshio could have contributed to the creation of such thermal layers.

The Black Tide

The collision took place on a winter's morning in an area known to have high maritime traffic, over the continental shelf extension of Shikoku with depths of approximately 1000m. February is typically the coldest month of the year in the northern hemisphere and being located in the temperate zone one could logically expect the sea surface temperature around Japanese waters to be cold as well, causing thermal layers commonly encountered in warmer months to be greatly diminished or even dissipate altogether. 

That would well be the case if not for the powerful Kuroshio Current which brings warm water from the tropics to the Japanese archipelago all year round. Kuroshio ( 黒潮 ) means black tide in Japanese. It is named because of its nutrient poor, deep blue, clear waters. It is one of the world's major oceanic currents comparable to the Gulf Stream of the Atlantic. The impact of this warm current on Japanese climate and maritime related industries is so great that the Japan Coast Guard monitors its activities constantly and issues daily reports.

JCG Quick Bulletin of Ocean Conditions
Path of Kuroshio & Tsushima Currents
Flow speed is 2 knots south of Cape
Ashizuri on 8th Feb 2021

Sea Surface Temperature off Cape
Ashizuri is about 21C on 8th Feb 2021

Because of the Kuroshio Current, the sea surface temperature south of Cape Ashizuri where the collision occurred remains at 20C to 22C in winter and between 26C to 28C in summer. So even in winter a significant layer of warmer water will exist above the colder water deeper below. How deep is warm layer gets depends on factors such as the current's flow rate, mixing from colder layers below and even eddies that form when the current is deflected by geological features or when it meets another ocean current, like the southward flowing cold Oyashio current from the Kuril Islands. 

It is a well known fact that the salinity and water temperatures can vary considerably especially at the boundaries of the tide, making navigation with sonar extremely tricky. To complicate matters, the path of the black tide is not always fixed and can sometimes shift quite drastically in what is known as the " Great Meandering " ( 黒潮大蛇行 Kuroshio Daidako ) especially off the Kii Peninsula east of Shikoku Island.

Sea Surface Temperature 20.6C
Flow Direction 070
Flow Speed 0.94m/s ( 1.88 knots )

Significant Wave Height 1.59m
Peak Wave Period 5.2s
Direction 305 deg

Surface Wind 25.5 knots
Direction 310 deg

The waters around the collision site is 
approximately 1000m deep.
Bathymetry from Japan's Submission to
the Commission on the Limits of the
Continental Shelf.

Maritime traffic density 2012
Image : shipmap.org

The Aftermath

The JMSDF has not been all forth coming with information on the collision. There were no mention of the incident on its website and social media accounts. The Minster for Defense and the Chief Cabinet Secretary did have press conferences and the MOD had a press release, but that was it. Some of the images and videos came from the JCG but mostly they were from the news media. Investigations are ongoing and hopefully the findings will be released soon. 

Since the Kuroshio Current dominates over almost the entire Pacific coast of Japan, I am convinced that the collision has something to do with it, barring other factors such as human error. Its high flow volume of very warm water creates a perpetual summer-like condition to Kyushu, Shikoku and Western Japan extending eastwards to the Kanto region at times. Its ever changing flow axis with major deviations and meandering and its multitude of eddies and countercurrents where there are deflections by land masses and confluences with other currents means that it is as unpredictable as can be, creating treacherous acoustic environments for submarine navigation. 

As usual, most accidents are caused by cumulative errors committed by all parties involved, but sometimes it can boil down to just pure bad luck, like being at the wrong place at the wrong time. The Soryu unfortunately has quite a long history of mishaps .... from electrocution and burns at the shipyard to attempted suicide and the accidental drowning of three petty officers within the flooded areas of the sail during routine operations in 2012. 

At the time of writing, the Soryu is back in Kobe where the Mitsubishi Heavy Industries Shipyard is located, presumably for damage assessment and repairs. Even though her pressure hull wasn't damaged, it could still possibly be out of active duty for several months and the repairs could cost several tens of millions of dollars.

Cmdr Koji will likely be relieved of his command regardless of the cause of the collision and the outcome of the investigations. His career as a sub-driver or even his future in the JMSDF could already be jeopardised. 

Meanwhile, the MOD decided that a 3.5 hour delay in incident reporting due to communications failure is utterly unacceptable and the JMSDF has pledged to ensure the availability of satellite phones on their vessels and boats.

Cmdr Koji Keisuke
Photo : JMSDF

Foot Note : Cape Ashizuri

It would not be right to end this article without elaborating on Cape Ashizuri. Known in Japanese as Ashizuri Misaki ( 足摺岬 ), this is the southernmost point of Shikoku Island. It is located in the remote western part of Kochi Prefecture where the pristine Shimanto River lies, with rugged coasts and beautiful night skies. 

Cape Ashizuri Lighthouse
Photo : JNTO

I had visited Cape Ashizuri in Feb 2017, after completing the Kochi Ryoma Marathon. Accessibility was an issue as the rail network did not extend to that region and even driving along the winding coastal roads was tedious and time consuming. But the effort was well worth it.

The Cape lies within the Ashuzuri-Uwakai National Park and it has majestic sea cliffs that towers above the vast expense of the Pacific Ocean. I remembered that it was extremely windy when I visited the Cape Ashizuri Lighthouse and walked through the tunnel of camellia which was in full bloom.

Cape Ashizuri is the southernmost
point of Shikoku Island. Statue
of John Manjiro in the Background.
Photo : Author

Another attraction at Cape Ashizuri is the statue of John Manjiro ( 中浜万次郎 ), a Japanese whose remarkable story I first learnt only during that visit. Manjiro had hailed from Nakanohama, an area known today as Tosashimizu, not far from Cape Ashizuri. 

Manjiro came from a poor family and lost his father at a young age. In 1841 when Manjiro was fourteen years old, he left home to work on a fishing vessel to help make ends meet. Unfortunately, due to inclement weather, he was shipwrecked on an uninhabited island off the coast of Japan for six months. Manjiro was eventually saved by the captain of a passing American whaler who named him John and brought him back to his hometown of Fairhaven, Massachusetts, so that he could be educated. 

Statue of Nakahama John Manjiro
at Cape Ashizuri. Photo : Wikipedia

Manjiro stayed in America for ten years, learning English and the science of navigation among other things, becoming the first Japanese to achieve long term residency in America. All that during an era when the ordinary Japanese were forbidden to travel or interact with foreigners! He would later join a whaling ship and work his way up to become the first mate and even participated in the California Gold Rush, earning enough money to fund his journey back to Japan. 

Upon his return, instead of meting punishment for violating the travel ban, the Shogunate government found his knowledge in English and foreign ways valuable and made him an advisor. He was also the translator for Japan's first trans-Pacific delegation to San Francisco and was appointed a lecturer at the Kaisei Institute dedicated to the teaching of foreign languages, science and advanced western technologies, paving the way for the Meiji Restoration and the industrialization of Japan which followed shortly. 

John Manjiro's story is worthy of an article all by itself but fortunately all the details can be found here.

Taigei : Japan's Super-Duper Next Generation Big Whale-Class Submarine

 

Launch of JS Taigei ( SS-513 ) at Mitsubishi Heavy Industries'
Kobe Shipyard 14th Oct 2020. Photo : JMSDF

The Japanese Maritime Self Defense Force ( JMSDF ) had just revealed the name of its next generation attack submarine during its launch on 14th Oct 2020. It is known as the Taigei ( たいげい, 大鯨 ), meaning " big whale ". Post-World War II Japanese submarines had a tradition of being named after marine phenomenon or auspicious creatures, be it real or mythical. So while the previous generations of Japan's hunter-killer submarine ( SSK ) classes had been named after tides and dragons, this time though it might just be named after whales.   

The naming of warships, especially the first in a series, can be very important as this will generally also be adopted as the name of the class. The Japanese knew this well enough to even refer to the lead ship of a class as the name ship ( ネームシップ  nemu shippu). The name of the first-in-class also usually sets the tone and direction for the names of the subsequent vessels that would follow in the series. 

Kujira!

In Japanese, the kanji character for whale is 鯨. On its own, this is usually pronounced as kujira ( Kun-reading ) but when combined as a word with another kanji character it is usually read as gei ( On-reading ). 

Ukiyo-e painting by Hokusai of the appearance of a gigantic whale
in the Goto Islands of Nagasaki Prefecture circa 1830. Wikipedia  

Whales and dolphins have an important place in the culture of Japan's indigenous Ainu people. They have lived with and hunted these marine creatures for sustenance as far back as time immemorial and there are folklore and festivals to celebrate their special relationship with these animals. In other parts of Japan especially around the Kii Peninsular of Honshu, coastal fishermen have been whaling with traditional methods for several centuries. Large scale commercial whaling with modern pelagic fleets only began about a hundred years ago during the Meiji era and intensified after World War II when Japan faced an acute shortage of food to feed its people. Whale meat then became a major source of protein for many Japanese in post-war Japan. However, as their country became more affluent, the Japanese could afford to import beef, pork and other meats such that whale meat consumption is now uncommon. That's not surprising at all because whale meat is tough and not as palatable as beef. Wagyu or Japanese beef taste a million times better than whale meat, or any meat for that matter.  

Annual Whale Festival at Toba City, Mie Prefecture.
Photo : Mainichi Shimbun

As centuries of over exploitation has drastically reduced the whale population globally, the International Whaling Commission adopted a moratorium on commercial whaling in 1982. Japan is one of the handful of member nations that defied the moratorium and continued with large scale whale hunting, purportedly for scientific research. After decades of unsuccessful lobbying for the ban to be lifted, Japan eventually withdrew its IWC membership in 2018. Japan's insistence on commercial whaling which required millions of dollars of government subsidy annually might be the result of lobbying by powerful political groups with vested interests. It has alienated Japan with many anti-whaling nations including Australia, who vehemently opposed Japanese whaling activities in the southern oceans. Hopefully this senseless culling will stop in the near future.

On a lighter note, whales of various types are also featured in many Japanese manga and anime including Children of the Sea ( trailer below ), Tico of the Seven Seas and my favourite, Children of the Whale ( Kujira no Kora wa Sajo ni Utau クジラの子らは砂上に歌う ).

                                                                                      Children of the Sea Trailer                                                               

                                                                             

    

Submarine Names

While the navies of the world had been deploying surface vessels for centuries, the history of modern submarines only went back about a hundred years. Especially in the early years, submarines do not bear traditional names like their surface counterparts did but instead were assigned alphanumeric characters like U-47 or I-400. This was because the early submarines were generally of lower tonnage and were only considered as boats, and navies by tradition do not name small crafts and boats. 

Even has the design and function of submarines grew increasingly complex and with their tonnage possibly exceeding those of their surface counterparts, they were still called boats, again by tradition. The only thing that has changed in recent years especially post-WWII is nowadays almost all the world's submarines are named.

JMSDF's long standing tradition of naming its submarines after oceanic currents is very apt since they are vessels of the deep and are supposed to ride the currents to strike with precision. Being an island nation surrounded by the oceans, the various currents flowing around the Japanese archipelago would be of significance as they will have a huge impact on the climate and the way of life for the people. However, after decades of naming them after currents, there are now many Japanese boats of different generations bearing the same name like Kuroshio ( 3 ), Harushio ( 2 ) and Oyashio ( 2 ). This creates confusion especially when the JMSDF historically retires its submarines after only about twenty years in service and boats of two different generations with very similar sounding names are concurrently in active service. 

The arrival of the Soryu-class SSK changed this long standing habit with the entire class named after dragons. If anything, this allows for the instant distinction of submarine class and capability just from the name alone, well mostly, if you disregard the fact the the last two boats of the Soryu-class are actually powered by lithium batteries instead of the usual lead-acid accumulators combined with air-independent propulsion technology found in the rest of the class. Naming submarines after dragons are also apt as dragons, at least in East Asian culture, are powerful mythical creatures of the sea that even have the ability to unleash storms of unimaginable ferocity. 

With the completion of the 12 boat Soryu-class submarines, it is now evident that the JMSDF is naming the lead boat of the new class after a whale. That itself does not guarantee that the subsequent vessels will also bear names of whales. For all we know it might be a marine mammal series - sea lion, seal, walrus, dolphin, or a even possibly fish series. However, based on the naming pattern observed since 1955 and the fact that the Japanese love conformity and order, I would hazard a guess that the rest of the series will also be named after whales.  

Naming Submarines After Whales

  

The naming of submarines after whales ( and dolphins ) is not entirely novel as proven by the numerous US Navy submarines that bear such names : Finback, Narwhale, Porpoise, Grampus ( Risso's dolphin ), Whale, Dolphin and Cachalot ( sperm whale ). In the JMSDF though, that would be a first. Even more than ocean currents and dragons, whales share many characteristics with modern submarines and to name them after whales are definitely appropriate.

For instance, both are deep diving, air breathing, fearless hunters of the oceans. Most importantly the use of sound waves in echo-location for navigation, locating prey and even performing an acoustic attack to disorientate the prey are tactics common to both toothed whales, dolphins and the modern sonar-equipped submarine. 

In fact, the Japanese have nicknamed the JS Akishio, a decommissioned Yushio-class submarine which is currently on display at the JMSDF Kure Museum, as the Iron Whale ( 鉄のくじら tetsu no kujira ) and the museum itself, Museum of the Iron Whale.

The Iron Whale JS Akishio at the JMSDF Kure Museum
Photo : Wikipedia

IJN Ships Named After Whales

While the JMSDF never had a vessel named after whales until now, its predecessor the Imperial Japanese Navy ( IJN ) had the history of naming 3 of its submarine tenders after whales. They were chronologically the Jingei ( 迅鯨 swift whale ), Chogei ( 長鯨 long whale ) and the Taigei ( 大鯨 big whale ). 

Submarine Tender IJN Jingei. Image : Pit Road

The IJN Jingei and IJN Chogei were sister ships that were the Imperial Navy's first purpose built submarine tenders. Launched in 1923 and 1924 respectively and with a standard displacement of 5160 long ton, the Jingei-class submarine tender were designed to perform multiple roles such as being the submarine division commander's flagship with the ability to resupply and support the communications and command and control for a division of 9 medium type submarines. They could also provide for crew accommodation, perform simple repairs and carry out torpedo maintenance works. They were armed with 4 x 140mm naval guns and 2 x 76mm anti-aircraft guns and a myriad of 25mm autocannons and 13mm machine guns. After 1930 they were even equipped with a float plane. 

Despite this seemingly impressive list of armament and capabilities, due to speed and size limitations, the Jingei-class tenders were unable to support the IJN's largest fleet submarines. They were largely obsolete by the time WWII commenced and were superseded by the IJN Taigei.

Submarine Tender IJN Taigei. Image : Aoshima

Launched in 1933 under the restrictions of the Washington Naval Treaty, the IJN Taigei was constructed as a large submarine tender with provisions for later conversion into an aircraft carrier. It was designed to support a division of the largest Japanese fleet submarines. Although it was the first major Japanese ship to be constructed using electric arc welding which was then considered innovative, lack of familiarity with the technique lead to weak welds, a warped hull and the appearance of many cracks later. The ship also suffered from poor stability because of some inherent flaws with the basic hull design resulting from an unfortunate combination of a high freeboard with a shallow draught. Its diesel engines also proved problematic, churning out only half the expected output. Damage from a typhoon shortly after completion in 1934 further delayed its integration into the fleet which eventually occurred in 1938. 

Works to convert the IJN Taigei to a light aircraft carrier commenced in Dec 1941 in Yokosuka and was originally scheduled to be completed in 3 months. It involved the installation of a 185m flight deck and the replacement of the problematic diesel engines with steam turbines. However, numerous problems and issues including bomb damage from the Doolittle air raid on Tokyo delayed the completion until November 1942. The vessel was then renamed the IJN Ryuho ( 龍鳳 dragon phoenix ).  

IJN Ryuho 1/700 waterline series. Image : Fujimi

The IJN Ryuho would carry out many aircraft ferry missions and training missions throughout the Pacific War and was also involved in combat including the Battle of the Philippine Sea in 1944. It was critically damaged during the Kure air raid of March 1945, stricken on 30th Nov 1945 and scrapped in 1946. 

 

JS Taigei ( SS-513 )

The JS Taigei ( SS-513 ) is the first-in-class of a new generation of advance diesel-electric attack submarine built for the JMSDF. It was also known as the 29SS ( 平成29年計画潜水艦 ) as it was promulgated in the defense plans in the 29th year of the Heisei era ( 2017 ) or even the 3000 Ton Class Submarine ( 3000トン型潜水艦 ) as that was the intended displacement of the new submarine.

It is the successor to the already very capable Soryu-class SSK with improvements in hull design for extreme quietness and impact resistance. The propeller and hull shapes are optimised to reduce flow noise generation and the submarine will adopt a floating floor structure with floorboards being attached to the inner shell via a buffer mechanism to reduce the outward transmission of vibrations and to protect the submarine against exogenous shock waves. 

Incorporating advance optical fiber technology, the integrated sonar suite comprising of a bow array, flank array and towed array, is designed to detect a future generation of very quiet submarines of Japan's near-peer rivals. The bow cylindrical array has a conformal horseshoe shape for improved directivity while the flank array has been changed from the conventional piezoelectric type hydrophones to an optical fiber hydrophone array making it smaller and lighter with reduced power requirements and reduced susceptibility to electromagnetic interference from within the submarine. The towed array has also been similarly infused with optical fiber technology for improved directivity and sensitivity.

The torpedo countermeasure system ( TCM ) installed on the Taigei is similar to those found on the last 5 Soryu-class submarines. The Type 1 Mod 1 non-hull penetrating photonics mast / periscope is said to be a licenced version of the Thales CM010 produced by Mitsubishi. Unlike traditional periscopes, these modern prism-less digital sensor masts only require very small apertures through the pressure hull for cabling and that preserves the integrity of the hull. They need not be directly above the user and are much more compact and can be housed entirely in the sail. This provides flexibility to the location of the control room which can be moved from the cramped upper deck to the more spacious second deck. Other areas of innovation are found in the submarine's C4ISTAR control systems which features enhanced combat management system and tactical display consoles. It is believed that the Taigei will be armed with japan's most advance Type 18 (G-RX6 ) torpedoes and the trusty Harpoon anti-ship missiles. 

JS Taigei Innovations.
Original image without annotations : Maritime Staff Office.

Just like the last two boats of the Soryu-class, the JS Taigei has a high efficiency power generation and storage system which utilises diesel engines and lithium-ion batteries, a combination which completely negates the need for an air-independent propulsion system. The lithium batteries, likely the Lithium Nickel Cobalt Aluminium Oxide ( NCA ) variety that populated SS-511 and SS-512 as well, were developed by Japan's leading battery maker GS Yuasa. They have many advantages when compared with lead-acid batteries, including having a higher energy density, a greater depth of discharge, a greater efficiency, a shorter charging time, a lower rate of self-discharge, a longer lifespan and also being lighter and more compact. The only disadvantages are cost and the increase in the risk of combustion which can be somewhat mitigated through the incorporation of special protective circuitry.

All these advantages of lithium-ion battery technology will translate to better endurance, higher dash speed, and better survivability for the submarine. To rapidly charge its lithium batteries, the Taigei will feature a new snorkel power generation system which involves improvements to the snorkel, diesel engines and the generators.

Externally, the Taigei looks rather similar to the Soryu submarines with the same hull form, diving planes, propeller and x-shaped rudder. Its interior however is designed to accept female submariners with separate bunking facilities. This is also a first for the JMSDF as their silent service has only recently lifted restrictions on the placement of female personnel onboard submarines.

Built by Mitsubishi Heavy Industries at its Kobe shipyard at a cost of 80 billion yen ( US$800 million ), the JS Taigei was launched and named on 14th Oct 2020 by Defense Minister Kishi Nobuo ( 岸信夫 ) who is actually ex-Prime Minister Abe Shinzo's brother. The commanding officer of the pre-commissioning unit is 45 year old Commander Tsuchiya Tooru ( 二等海佐 土屋亨 ) who will very likely continue as the first CO upon the Taigei's commissioning.

The boat is scheduled to be commissioned in Mar 2022 and will be converted into an experimental submarine for the testing and evaluation of new technology for Japan's next generation submarines. This arrangement will allow existing JMSDF submarines to dedicate their entire service life to operational and training matters, rather than the existing routine of having every submarine in the fleet to take turns performing the testbed role. Currently, the Japanese Ministry of Defense has allocated funds for three more submarines of the Taigei-class, SS-514 ( 30SS ) $697million, SS-515 ( 31SS ) $698million and SS-516 $702million. Budgetary approval for a fifth boat had been submitted on 30th Sep 2020. Following tradition, Mitsubishi and Kawasaki will each take turns building the submarines until the entire class is completed. 

The following photos and video of the launch and naming ceremony are courtesy of the JMSDF.

The JS Taigei is the 1320th ship ( 第一三二〇番船 )
constructed at the MHI Kobe shipyard.

Defense Minister Nobuo Kishi cutting rope with silver axe

Ceremonial Silver Launching Axe

Streamers activated as boat is launched

Colourful balloons released as boat moves down the slipway

More fitting and trails await the JS Taigei

                                                                                   JS Taigei Launch video                                                                                                                          

　　　　　　　　　　　    

Likely Names of the Taigei-Class Submarines

Assuming a naming convention comprising of whale names, other names likely to be selected for the submarines in the series will definitely include those already given to the IJN ships in the past and that will include Jingei and Chogei. However, to differentiate itself from its imperial past, JMSDF will omit the use of kanji characters in the written form of the ship's name and instead write it in the hiragana form. So the Japanese name of the submarine Taigei will be written as たいげい but not 大鯨. 

This practice of kanji omission is regrettable and rather frustrating. Many different kanji characters share the same pronunciation. To present a name comprising of a string of kanji characters in its syllabary hiragana form may not reveal the actual characters and therefore their meaning at one look. There will be none of this ambiguity when the names are presented in kanji, like in the bad old days. 

Below is a compilation of possible names for subsequent vessels.

			Kanji	Hiragana	Alphabetic	Meaning
			瑞鯨	ずいげい	Zuigei	Auspicious
			巨鯨	きょげい	Kyogei	Huge
			雪鯨	ゆきげい	Yukigei	Snow
			祥鯨	しょうげい	Shogei	Blessed
			雲鯨	うんげい	Ungei	Cloud
			魔鯨	まげい	Magei	Magical
			玉鯨	たまげい	Tamagei	Jade
			宝鯨	ほうげい	Hogei	Treasure
			仁鯨	じんげい	Jingei	Kind
			迅鯨	じんげい	Jingei	Swift
			騰鯨	とうげい	Togei	Leaping
			闘鯨	とうげい	Togei	Fighting
			涛鯨	とうげい	Togei	Wave
			韻鯨	いんげい	Ingei	Rhythm
			長鯨	ちょうげい	Chogei	Long
			遠鯨	えんげい	Engei	Afar
			淵鯨	えんげい	Engei	Abyssal
			焔鯨	えんげい	Engei	Flaming
			琥鯨	こげい	Kogei	Amber
			古鯨	こげい	Kogei	Ancient
			皇鯨	こうげい	Kogei	Emperor
			煌鯨	こうげい	Kogei	Glittering
			王鯨	おうげい	Ogei	King
			螢鯨	けいげい	Keigei	Fluorescent
			楽鯨	らくげい	Rakugei	Merry
			雷鯨	らいげい	Raigei	Thunder
			舞鯨	まいげい	Maigei	Dancing
			襲鯨	しゅうげい	Shugei	Attacking
			寿鯨	じゅげい	Shugei	Longevity
			若鯨	わかげい	Wakagei	Young

Some Taigei Specifications and Manga Art by @ginntokii via twitter

Taigei-Class Specifications

Displacement ( surface ) : 3000 Tonnes 

Displacement ( submerged ) : 4200+ Tonnes?

Length 84.0m

Beam 9.1m

Draught : 10.4m

Complement : 70

Engine Type : Diesel-Electric

Storage : Lithium-Ion Battery - Lithium Nickel Cobalt Aluminium Oxide ( NCA ) ?

Propulsion : Screw Propeller x 1

Speed : 20 knots submerged

Range : ?

Operational Depth : ?

C4ISTAR

Submarine Combat Management System ( 潜水艦情報管理システム )

Core Network System ? ( 基幹ネットワークシステム )

Submarine Tactical Display System ZQX-12 ( 潜水艦戦術状況表示装置 )

Information Processing Subsystem OYX-1 ( 情報処理サブシステム )

Electronic Support Measures : NZLR-2 ( 電波探知装置 )

Surface Search Radar : ZPS-6H ( 対水上捜索用レーダ )

Sonar : ZQQ-8 Fiber-Optic Array ( ソナー ) ( 水中音波探知機 ) 

Periscope : Non-penetrating Periscope Type 1 Mod 1 ( 非貫通式潜望鏡1型改1 ) 

Armament 

HU-606 21 inch ( 533mm ) Torpedo Tubes x 6 ( 魚雷発射管 )

Type 18 Heavyweight Torpedo ( 18式長魚雷 )

UGM-84 Harpoon Missile ( ハープーン対艦 ミサイル)

Others

Torpedo Countermeasure System ( 潜水艦魚雷防御システム )

Snorkel Power Generation System ( スノーケル発電システム )   

The JMSDF currently has 9 Oyashio-class submarines and 11 Soryu-class submarines in operational service. The two oldest Oyashio boats have already been converted into training submarines, JS Oyashio TSS-3608 ( ex-SS-590 ) in 2015 and JS Michishio TSS-3609 ( ex-SS-591 ) in 2017. The last Soryu boat JS Toryu ( SS-512 ) will be commissioned in Mar 2021 and together with the JS Taigei, these two submarines will enable the JMSDF to achieve its goal of fielding 22 submarines by the year 2022. This fleet size is important to counter China's increasing number of sophisticated AIP capable Type 039A submarines.

With enhancement and innovation featured in virtually every sub-system, the Taigei looks set to revolutionize submarine design and operations. The fact that it will be a dedicated experimental submarine means that the JMSDF can push the boundaries of advance technology in a continuous manner and introduce them to its operational fleet at the earliest opportunity, without having to wait years and decades for a new class of submarine to be constructed. This timely introduction of advance capabilities has already been observed among the Soryu-class boats, like the torpedo countermeasure system that was installed from the 8th to the 12th boat, and the lithium-ion battery of the last 2 boats of the series. The Taigei will no doubt accelerate the testing and implementation of such future technology within the Japanese submarine fleet. And that is definitely a good thing. 

May the Taigei be the first in a pod. Ganbatte Kudasai!