Koko Kyouwakoku (Republic of Koko)

time for a new entry. Forgive my huge chunks of text and a bit of over-exaggeration, those are my favourite Kokoan heavy cruisers, themselves a personal take on my favourite IJN cruisers...

Senjo Class Heavy Cruiser:

By 1933, under the term of the London Naval Treaty, Koko no Kaigun's staff had submitted to the fact that some of the earlier light cruiser units, despite beign just over 10 years old, had to be disposed in order to give the fleet a chance to field comparable units to those in service with potentual hostile Navies. The naval staff thus concretely accounted the plan to disarm, scrap or convert to training uses the six Kashino Class light cruisers in order to built threee new modern units in their place. The 24.000T that would have been freed this way would have allowed for construction of three newer light cruisers, each displacing 8.000T standard. First draft called for a Mogami-like cruiser with a reduced displacement, sporting four main gun turrets instead of five. This first plan was immediatley revised in late 1933 under Morimoto first reamament bill: ignoring treaty limitations on displacement the new project started from a required battery of fiteen guns. By mid 1934, when the three units were ordered for construction, the design had grown to 9.994T standard. The ship also reached more similarities with the Takao class than the Mogami, as KnK wanted enough flag space to allow the ships to easily act both as cruiser and destroyer flagships as necessities dictated. Armament was finalized at fifteen 152mm guns in five triple turrets, eight 127mm guns in four twin shielded mounts and sixteen 13mm anti-air machine guns in four quadruple mounts. Twelve torpedoes plus reloads fitted in four triple launchrs were also planned. Designers opted specifically on a modified version of the IJN Mogami turrets housing 152mm guns instead of 155mm ones in order to exploit older stocks of ammunition left from the earlier pre-WNT cruiser classes and the Goryo class battlercruisers, all of which had been scrapped. As for protection, side armor was to be 102mm thick, deck 35mm, with a 14mm bulge protecting the engineering spaces. Top speed was planned at 37knots. fire control would have been provived by a Type94 director set with a 6-m rangefinder fitted above the bridge structure, backed by an auxiliary director mountd atop the hangar. 4,5m rangefinders and a Type91 director would have served as the 127mm guns fire control. The main striking differencies, compared to a Japanese Takao clas ship, were the hull, 1,8m longer while keeping the same beam and draft, featuring a sharper stem and lacking the distinctive sloping stern, the different main armament and the hangar structure located some 2,5m aft, allowing the aft funnel trunk to be angled backwards.
The lead ship, senjo, was laid down at Kousaten Navy yard in late 1934, with Tenji following at the same yard by mid 1935. Fujiwara, the third sister, was ordered and started at Toumachi Naval Arsenal in early 1936.
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As the three ships were under construction, Morimoto's second rearmament bill passed, at this point all naval construction currently ongoing in Koko could have ingored traties in it's entierely, both for displacement and numbers. This way a new dedicated, smaller, project was started for a new class of light cruisers (with the six Kashino no longer in danger of beign demilitarized) and the three Senjo were ordered to be rearmed and modified as heavy cruisers. three more ships were also ordered, to bring the total count to six vessels. The 152mm turrets were mothballed, reserved for arming the Yashima class battleships, whose design phase started almost immediately, and newer 203mm model-E twin turrets were manifactured. The triple 610mm torpedo mounts were also replaced with newer quadruple ones -initially planned to arm the refitted Kumoi class cruisers- for a total of sixteen torpedoes plus eight reloads. Light anti-aircraft armament was increased to four twin 25mm and two quadruple 13mm machine guns, the latter on sponsons abaft the bridge, in place of a lookout station, most of which were removed. Redesign included an increase of armor protection, with the side belt reaching 127mm of thickness around boiler and engine rooms. Deck armor reached 65mm and the anti-torpedo system was vastly enlarged with it's thickness increased from 14 to 58mm. The new anti-torpedo system also increased the beam to 20,7m. Armor for the main guns varied from 25mm of the turrets themselves to 76mm of the barbettes. fire-control was upgraded, with a new director for the main guns. A composite director-rangefiner tower replaced the spit system of the 127mm guns, and a machine-gun director was added between the funnels. the most noticeable modification was the new aircraft-handling deck: the hangar superstructure was removed and the mainmast shifted aft by almost 23 meters. Airwing also changed from the planned three Nakajima E4N to two Nakajima E8N and a Kawanishi E7K. the foremast was also shortened in height and recieved an RDF room. One last modification done before launch was the addition of a straight bulbous bow below the waterline, a feature that had been studied by Koko no Kaigun designers during the project phase of the kazami class light cruisers and the Yashima class battleships. The resulting ships measured 205,5m overall, with a waterline lenght of 202,6m. Beam was 20,7m and draft had increased from 6,3 to 6,5m. The increase of beam, the new bow, reworked armament and increased armor had took the cruisers displacement up to 14.248T at standard load, for a full load walue of 16.253T. Range was kept as planned at 8.000nm at 14knots, thanks to additional fuel tanks located inside the enlarged bulges of the anti-torpedo system, Speed dropped 1knot from the planned value to 36knots, a figure still deemed highly satisfying.
Senjo was launched in ealry 1938 and commisoned by the end of the year. Tenji, also launched during 1938, was completed ad commissioned by spring 1939. The two units formed Sentai 5.
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Fujiwara, built at Toumachi, enjoyed a much quicker construction than her sisters, so that in 1937 she had already been launched. Reworking of the main gun barbettes had been completed, as it was the armor increase and most of the other features planned, but the ship still retained the older curved bow. For this reason Fujiwara underwent a longer fitting-out phase, during which the boww was reconstructed to the new standards. As a consequence of this, the Naval staff choose to equip the cruiser with some of the improvement planned from the second batch ships: eight, more powerful, boilers were fitted instead of then, allowing for more command space inside the lower decks of the bridge. The ship also recived a redesigned and smaller foremast, a new 8-m rangefinder unit on her main-gun director and two extra twin 25mm machine guns in place fo the quadruple 13mm ones fitted on Senjo and Tenji. The airwing was also further updated to two Mitsubishi F1M and one Aiche E13A floatplanes. After completing all of her modifications Fujiwara was commissioned in January 1941, becoming Sentai5 flagship in place of Senjo, thanks to her increased command spaces.
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First ship of the second batch, the cruiser Chichibu was laid down at Kousanten Navy Yard in 1938, shortly after the launch of her sister Tenji. fitted from the start with all the features retrofitted to Fujiwara, she was launched in 1940 and commissioned by fall 1941. Aestethically she could be told apart from Fujiwara because of the different steam-pipes layout on her funnels. She was too attached to Sentai 5 upon commissioning.
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The fifth and Sixt units, Jimmu and Nintoku, were laid down at Kousaten and Toumachi yards in 1940 and 1941 respectively, but both were not yet in service when the Pacific war started. The four active ships recieved arctic camouflage and sailed for the Aleutians to support the invasion of Attu and Kiska. Later on all four took part in the Battle off Turf Point, with Tenji and Fujiwara beign credited for the sinking of the USS Trenton. After supporting the invasion of Adak, Sentai 5 ships kept patrolling the waters around western Aleutians before finally recalled home by early-January 1942.
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After beign quickly repainted in standard grey the four Senjos departed for southern waters accompained by Amagi and a few Destroyer squadrons to support Japanese landings in Borneo. While Patrolling off Balikpapan with Amagi, during the night of January 25th, The ships engaged in combat the British Battlecruiser Irresistible and her escorts, which were on a bombardment mission of the Japanese beacheads. During the battle Senjo and Chichibu engaged british Destroyeres before breaking off the Action as they came under fire from the Battlecruiser Tiger, suffering moderate damage in the process. before veering away they each launched a spread of torpedoes, that, despite failed to hit their mark, forced the British ship to disegngae too. Tenji hit HMS Exeter twice, setting her on fire before recieving a direct hit from Irresistible 16-inch guns on her port side which destroyed one of her catapult and knocked one of her turbines out of action. Tenji escaped further harm when Amagi diverted Irresistible attention on her, also allowing Fujiwara to execute a torpedo run, hitting Irresistible with two long lance torpedoes that jammed one of her guns and flooded two boiler rooms, forcing the Battlecruiser to retreat. The Fujiwara exchanged gunfire with the Rechercean light cruiser Ravensthorpe, hitting her repeatedly while recieving no hits in return. Shortly after, Senjo and Chichibu exectued one last torpedo attack on the enemy fleet, hitting HMAS Vendetta, wich blew up and sank. The ABDACOM fleet retreated afterwards.
With Tenji, Senjo and Chichibu returning to Koko for repairs, Fujiwara was left as the sole Sentai 5 ship still depoyed in the southeast Asia area. She kept escorting convoys and guarding beacheads before being rejoined by Senjo and Chichibu by the end of February. The three ships took part in the Battle of the sunda strait, assiting IJN Mogami and Mikuma in the sinking of the USS houston HMRS Mondrain and HMAS Perth. By late march Senjo, Chichubu and Fujiwara returned to Koko, beign rejoined by Tenji sortly after as her repairs were completed. Chichibu and Fujiwara were present at the Battle of Coral Sea, and all four were part of the joint IJN and KNK main body during the Battle off Midway and took no part in the action whatsoever.
After five months of uneventful patrols split between Midway and the Aleutians the four Senjos departed once again fro Kokoan waters bound for the Solomon Islands, here they took part in the Third naval battle of Guadalcanal. Fujiwara proved herself to be the most succesful of her sisters once again, hitting the USS colorado with a torpedo and damaging the USS Helena with gunfire. She also shared the sinking of the light cruiser Concord with the IJN Takao. Both Senjo and Tenji hit the USS San diego, later finished off by Sendai, suffering five and eight hits in return, the most serious ones knocking out of action the forward starboard 127mm mount on Senjo. Of the Four, Chichibu took the short end of the stick, suffering seventeen 8-inch hits from the USS Pensacola, which put out of action two main turrets, one 127mm mount, all 25mm guns at midship, damaged five boilers, started a fire at midship and forced the crew to jettison all torpedoes in order to avoid further trouble. Chichibu limped away from the battle making ten knots with a 12° list to starboard. She suffered 56 killed and 121 wounded, and was not back in service until late April 1943.
Meanwhile after been launched from Kousaten Navy Yard, the fifth ship of the class, Jimmu, completed her sea trials and was commissioned into Koko no Kaigun, joining her sisters into Sentai 5. Compared to her earlier sisters, she was fitted with newer main gun directors and the machine gun directors were moved further aft for better arcs of operation. The two wing lookout posts were eliminated, as it was for the two platforms located just abaft them, the lookout post at the top of the bridge lost it's shield too and the signalling lamp platforms abaft the bridge were expanded. An anti-aircraft command post was added above the navigation bridge and a ready-room for the anti-aircraft crew was added at midship. AA fit was also augmented by the addition of two extra twin mounts, bringing the count to sixteen barrels. Jimmu was also fitted from the start with a Type-21 air-search radar on top of the foremast. She also had a reduced number of portholes.
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Now part of a five-ship strong Sentai, Senjo, Tenji, Fujiwara, Chichibu and Jimmu reached Truk and then Rabaul, later taking part in the battle of Solomon Sea. Beign it a carrier battle their only action result was shooting down a few planes during the engagement. The sisters did not battled against surface ships again until the night of Semptember 5th 1943, when the Naval battle off Makira was fought near San Cristobàl Island. The Kokoan heavy cruisers managed to sink the USS Fresno (CL-84) and Newark (CL-88), the latter sunk with a combination of gunfire and torpedoes by Fujiwara, but failed to prevent the Americans to land their troops on the island. A little more than two months later, on November 28th the five cruisers, operating together with the IJN Aoba and Kinugasa, engaged a sizable US and Recerchean fleet led by the USS Baltimore in the battle of cape Zeele. The engagement started well for the Japanese/koakoan side, as two torpedoes launched by Jimmu hit and put out of action the light cruiser Mobile while Fujiwara repeatedly hit the Pasadena, knocking out of action her entire forward battery. Soon after The ships came under heavy and accurate fire from the heavy cruisers Baltimore and San Francisco, which hit Kinugasa twenty-five times, damaging her guns and engines and stopping the cruiser dead in the water when her torpedo tubes exploded. Jimmu opened fire hitting San francisco twice before beign hit in response by the Light Cruiser Cleveland, which scored three hits on the bridge, killing most of the personnel, including her commanding officer. Senjo veered right with Tenji and Chichibu, targeting Recerchean cruisers Stokes and Munglinup, hitting them four and seven times respectively before suffering four and six hits in return (whle Tenji recieved none). Senjo then attempted a torpedo attack against them but was in turn hit by a fish previously fired by the USS Fletcher. Fujiwara then engaged directly the Baltimore, hitting her four times and starting a fire on her aft superstructure. The American cruiser immediatley replied with extremely accurate radar-directed gunfire, hitting Fujiwara ten times in a few minutes, disabling both her after turrets and setting the deck on fire. Further hits caused a loss of pressure in boiler room four. As soon as the USS Montpellier and Denver joined the battle, they scored multiple hits on Chichibu. San Francisco then bracketed Aoba, landing five accurate hits on her port side, disabling the 120mm guns and starting fires near the torpedo launchers. With the tide of the battle clearly towards the American side, Fujiwara's captain ordered the fleet to retreat. As escorting destroyers made smoke all cruisers reversed course and made as much speed they could to leave the battle area. Kinugasa's survivors were hastly transferred on the destroyer Utsuho wich left last making flank speed while under fire from the entire American fleet. Kinugasa rolled over and sank with 511 dead shortly after.
After retreating to Rabaul the ship were given temporary repairs and thens teamed back to Koko home waters. With the eception of Tenji, who miracolously escaped damage, all ships had suffered serious damage during the battle. Jimmu was out of action until January 1944, Chichibu and Senjo rejoined the fleet in March and fujiware ultimately did it only by late April. In May they salied as escorts for Koko no kaigun carrier fleet during the indecisive battle of Laysian. Between May and September all ships recieved their main wartime refit: most of the portholes were sealed off, and anti-aircraft command post was added on top of the compass bridge (except on Jimmu wich already had since completion), Type 13 and Type 21 air-search radars and Type 22 surface search radars were fitted (Except the Type 21 on Jimmu already fitted) and the anti-aircraft suite was vastly increased, totaling at least 50 guns for each ship. The rangefinders from n°1 turret were also removed (except from Jimmu, which was altready completed without it). All five took part in the second Battle of Midway, during which the Kokoan carriers Inuwashi, Ahodori and Tobuio were sunk.
On November 13th 1944, Tenji was traveling between Toumachi and Midway for a supply run toghether with four destroyers when she was hit by three torpedoes from the USS Sivlersides. The cruiser immediately took on water and developed a 22° list to port, in a little mroe than six minutes Tenji rolled on her side and sank, taking 238 men with her.
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At the time of Tenji's sinking, the last of the sixth sister was still undergoing her fitting out at Toumachi Naval Arsenal. Nintoku, the last unith of the class, had been laid down in 1941 and launched in 1943, but her completion had been delayed by design changes and by building priority given the Destroyer and escor ships production. Compared to ther sisters Nintoku featured a straight flare on her forecastle in order to ease construction, her stern lines were also slighly finer, she had also almost no portholes on her hull and an improved hydrophone. Displacing slightly more than her sisters, at 14.304T, Nintoku also had her armor increased to 127mm abaft the amgaszines and 140mm around the engine rooms. Barbette armor also reached 100mm. More notable, her fire control sistem had been forther updated, with a new rangefinder-director fit. This was also reflected by the rearranged bridge levels, featuing just a two level deckhouse compared to the thre-level ones of her sisters.The forward searchlight platform was placed lower than that of the other ships in order to give better firing arcs to the 25mm machine guns, which also recieved a new director for them. AA-wise, nintoku sported fifteen triple and twenty-five single 25mm machine gun mounts for a total of 70 barrels. She also carried sixteen depth charges on the faintail. Another difference was in her radar suite, She only retained the Type-22 surface search radars, while the air-search set was a kokoan built-mattress version of the thiarian R7FA obtained in early 1944 by the submarine Ki-38 during the second technology exchange between Koko and Thiaria. Nintoku also fitted the Thiarian R5CD fire-control radar for her main battery and the R12CAD fror the dual-purpose armament. Two aichi E16A replaced the Mitsubishi F1M as the main reconnaissance plane. Finally, the ship was painted in a blue-black camouflage pattern for night operations.
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In further refits all the other ships recieved the Thiarian fire-control radars and variants of the Nintoku camouflage pattern, anti-air guns were further augmented, reaching a maximum of eighy-one barrels on Fujiwara: nine triple, ten twin and thirty-four single mounts. All five surviving Senjos took part in the Battle of the Philippine Sea in June 1945, testing with good results their new anti-aircraft directors. Despite the 25mm machine guns proved to be clearly lacking enough caliber and rate of fire to be satisfactory anti-air weapons, the Senjo class performed well thanks the the Thiarian fire-control, shooting down by themselves, or together with other units as high as 13 of the 49 US planes shoot down by Kokoan units during the battle.
After the Americans started their invasion of the Philippines, all five ships reached Brunei, later joining the enormous center force led by Vice Admiral Takeo Kurita. Escaping undamaged by the attempted submarine ambush made by US submarines in the Palawan passage during the night of 23 october the five Senjo class units provided air cover during the battle of the Sibuyan Sea, ultimately emerging unscathed off Samar on October 25th morning. Waiting for the Kokoan/Japanese fleet were three groups of US escort carriers -Taffy1, 2 and 3- and a squadron of co-belligerant Thiarian ships made up by two battleships, two heavy cruisers, three light cruisers and twelve destroyers. A former ally that now had to be treated like an enemy. The Fleet split and the Japanese engaged Taffy 3, while the Kokoan ones charged Taffy 2. At first the Thiarian squadron engaged the, closer, Japanese fleet, allowing Koko no Kaigun squadron to engage Taffy2 unmolested, battleship gunnery beign accurate enough to damage and further slow down the escort carriers. Kokoan cruisers then closed in and engaged the CVEs escorts. Fujiwara quickly put out of action the USS Haggard, while Hailey and Abercrombie suffered multple hits from Nintoku and Senjo's gunfire before making smoke an retreating. Chichibu opened fire on the carrier Natoma Bay shortly after. Jimmu easily disabled and sank the USS Oberrender, but not before she managed to hit the battleship Owari with one of her torpedoes. Before Taffy 1 aircraft came and started attacking the Kokoan ships, soon followed by Three destroyers and a Battleship from the Thiarian squadron, Manila Bay had been sunk by the battleship Amagi, and Fujiwara had sunk by herself with a combination of gunfire and torpedoes both USS Marcus Island and USS Kadashan bay. Thiarian battleship Athartha opened fire on the battleship Suruga, while the three destroyers charged the closest ship they had: the cruiser Chichibu. The kokan cruiser opened fire, scoring hits that heavily damaged one of the enemies, but the other two ships manged to launch their torpedoes, which were -ironically- reverse-engiinered version of the Japanese long lances, exchanged with Thiaria for the very same radars the Kokoan ships were fitted with. Despite evasive manouvers were promptly executed Chichibu was hit by three torpedoes, one of them penetrating and exploding rigth in the engine room, stopping the cruiser dead in the water. The ship became an easy target and was soon hit by five bombs dropped by Taffy 1 planes. Burning fiercely Chichibu was abandoned, strangely sinking on an even keel and taking with her all but 133 of her crew. Despite the serous losses, all of taffy 2 escort carriers except the Ommaney Bay had been sunk or heavily damaged, as it was for most of the escorts. Athartha, after inflicting serious damage on Suruga, was now beign put on the defensive by concentrating fire coming from the battleships, Amagi, Kii, Omi and Mikawa. As it appeared that Kokoan units would have been able to break the blockade and rejoin the IJN fleet the order to withdraw issued by Admiral Kurita came as a surprise. Without further ado, the Kokoan units regrouped and departed for San Bernardino strait. during the night between 25 an 26 October, the retreating fleet was intercepted by Task force 34 under the command of Admiral Willis A.Lee. Strong of the Battleships Iowa, New Jersey, Washington, Missouri, Wisconsin, Massachussets, Alabama, the Battlecruisers United States and Constitution, the recearchean battleships Resolute and Dauntless, four heavy cruiser, six light cruisers and eleven destroyers Admiral Lee tok his revenge for the defeat he suffered almost three years earlier during the second naval battle of Guadalcanal. Despite losing the Battlecruiser United States to gunfire from the Amagi and Nagato, Lee and his ships sank the Battleships, Musashi, Mutsu and Nagashiro, also heavily damaging Kii and sinking the heavy cruiser Kumano. While trying to screen Nagashiro, Nintoku was hit nine times by 16-inch shells from the USS Missouri. Burining with her rudder jammed, the Kokoan cruiser became a prime target for most of the American fleet, eventually blowing up and sinking with all hands. Fujiwara managed to hit the cruiser New Orleans twice, then torpedoed the Alabama but then she was torpedoed herself by the destroyer Porterfield, disabling her outer starboard propeller. After the disatrous battle, the battered Kokoan fleet eventually took shelter in Manila, then split. Most ships immediately set course or Koko, Senjo departed for Brunei, while Fujiwara, that suffered further hits from plane attacks on October 26, was left in Manila to repair the damage. Still under repairs, on October 29th, she came under attack from Task force 38 planes, suffering slight damage, and further delaying her departure. By November 4th, four of her eight boilers had been brought back online, allowing the ship to leave Manila and make 15knots. Just two days, off her voyage -ironically the same day Koko uprising started- Fujiwara was attacked again, this time by American Submarines. Hit by two torpedoes the Kokoan cruiser suffered all four operable boilers flooded, lost steering and developed an 11° list to starboard. Towed to Santa Cruz, Luzon, the ship now had to face further problems: as the Koko uprisings had just started every seaman had to choose his loyalty, and the Japanese troops stationed on the philippines feared that Fujiwara's crew would have joined the rebels like most of Koko no Kaigun crews had done. The cruiser thus had her entire complement temporarily interned while Japanese repair teams started working on the damaged ship, with the chance of getting her in service for the IJN eventually. Some of her crew were eventually allowed back to the ship to help with the repair works and to man the anti-aircraft guns in case of enemy attack. All this ended on November 25th 1944, when planes from the USS Ticonderoga attacked Fujiwara, hitting her with five torpedoes and four bombs. Despte refusing to die for as long as 30 minutes after suffering hits, Koko no Kaigun most succesful cruiser slowly rolled over and sank. Of her crew of 1.133 officers and men before the Battle of leyte gulf, eventually 693 returned home after the war. Of her, Admiral William "Bull" Halsey reportedly once remarked that "if there was a Japanese or Kokoan ship I could feel sorry for at all, it would be the Fujiwara"
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Senjo, after reaching Brunei on november 5th, became one of the few Koko no Kaigun ships to remain loyal to Morimoto, eventually joining the IJN ranks. She then joined the cruisers Ashigara and Haguro. Here she had her aft fire-control radar removed, and both aft sets of torpedo tubes were removed to increase space for supply and troop transport. She also retained a single Aichi E13A as reconnaissance aircraft. Anti-air suite was made of four triple, eight twin and twenty-six single 25mm machine guns, for a total of 54 barrels. Together with the Haguro and Ashigara, Senjo took part in the Battle of the Andaman Sea on February 3rd 1946, during which the three ships, while facing a siperior British fleet, managed to sink the Battlecruiser Irresistible, the same ship Senjo and her sisters had battled just over four years earlier at Balikpapan. Senjo continued her job as a troop and supply transport until June 8th, while steaming between Batavia and Singapore with Ashigara and Kamikaze Senjo was hit by five torpedoes fired by HMS Trenchant, wich also damaged Ashigara with two more torpedoes. Senjo capsized and sank shortly after, taking with her 685 out of 1.153 crewmembers.
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Jimmu, the only ship that managed to return to Kokoan water after the Leyte disaster, joined the rebels and surrendered to the US forces in March 1946 after Koko uprisings ended. Joining the co-beligerent fleet, Jimmu started her repairs in a devastated Toumachi Naval Arsenal. kokoan-built R12CAD and R7FA radars were fitted, and all 25mm machine guns were removed, replaced by twin 40mm/Type5 mounts, more portholes were sealed over. Works proceeded slow, so that the ship was not completed until the war was over. In 1947, Jimmu joined the newly reformed Koko Kaijou. she was repainted in standard grey, had the catapults and the torpedo mounts removed, with their hatched closed over, the aft set of searchlights was also landed. Retaining all her original electronics, with the exception of an USN machine gun director, all but six 40mm machine gun mounts were removed.
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Jimmu remained in service until 1950, when the newly built cruiser Daikakuji was commissioned. She was then decommissioned and scrapped, although one of her turrets was preserved and is now on display at the Yamasaki Naval Museum, outside Koko Kaijou Naval academy, Yamasaki, Koko Island.

Ships in class: (laid down-launched-commissioned - fate)

Senjo 1934-1938-1938 - Joined the IJN 1945, Sunk 1946
Tenji 1935-1938-1939 - Sunk 1944
Fujiwara 1936-1937-1941 - Sunk 1945
Chichibu 1938-1940-1941 - Sunk 1945
Jimmu 1940-1942-1943 - Decommissioned 1950
Nintoku 1941-1943-1945 - Sunk 1945

Hi all, this thread is not dead!

Kazami Class Light cruiser:

The genesis of the first Light Cruiser class built for Koko no Kaigun in more than ten years started with the Second Rearmament Bill passed by Morimoto's government in 1936. The Bill dictated the conversion of the then under construction Senjo class from CL to CA, and a new class of six units to fill the gap now open.
With no restrictions on displacement the ships were designed around the 140mm guns, the conversion of two Hayabusa seaplane Tenders into Light carriers and the cancellation of the last unit immediately made available nine triple turrets, enough to arm half of the planned Cruisers. This way by late 1936 board works had been done. The ships would have measured 176,1m overall, had a beam of 15,6 and a draft of 5,7. Displacing 7.149T standard and 8.935 at full load. Armament was composed of nine 140mm/50 guns in three triple turrets, two forward and one aft, two single 120mm guns augmented them as dual-purpose armament. Light anti-aircraft suite was made of two triple 25mm machine guns, one placed in front of the bridge and one on the aft superstructure. The ships also carried two quadruple 610mm torpedo tubes with a total of 16 warheads, half of them housed in armoured reload boxes. The torpedo launchers were fitted on centerline, with the aircraft-handling deck built above the aft set, the reload boxes were placed in a diagonal arrangement between the rotating tubes. The aircraft catapult was also placed between the reloads, squeezed between them were also the ventilation ducts for the aft boilers and the engine room. Armor wise, the belt was 65mm thick, decks 20mm, turrets 50mm on face and 30mm on sides and barbettes 50mm thick, there was no anti-torpedo protection given the ships tight beam.
The ships were fitted with six oil-firing boilers generating 100.472shp, powering four sets of turbines and driving four screws for an overall top speed of 35 knots. Endurance was 6.000 nautical miles at 18 knots. Aircraft complement was to be made up by two Nakajima E8N reconnaissance seaplanes. Complement was 458 officers and men. The cruisers were also the first units for Koko no Kaigun to be designed with a straight bulbous bow, as the Senjo Class ships, which were the first to be commissioned sporting that features, had been retrofitted with it during their construction.
Ordered in late 1936, all six cruisers were built at Toumachi Naval Arsenal. The lead ship, officially named Kazami, was started in late 1936, launched in 1937 and commissioned during the second half of 1938. A second ship, Onozuka, was commissioned by the end of the year, a Third one, Kagiyama, followed in 1939. Both looked identical to their sister.
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During the ships trials and initial months of operations smoke interference issues emerged when operating the shipboard seaplanes. This flaw was resolved by raising the funnel by 1,2m (4 feet). The third unit, Kawashiro, was completed and commissioned during the second half of 1940, and was the first unit of the class to be completed with the already heightened funnel. She had her two Nakajima E8N repainted from standard white to a brown-green camouflage and her anti-aircraft suite was augmented with the addition of two quadruple 13mm machine guns on each side of the aircraft-handling deck. Inubashiri, the fifth unit, was commissioned by mid 1941 and recieved the same improvements.
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Onozuka became the flagship of Suirai Sentai 1, the other four sisters were assigned to Sentai 7. All five sailed with Koko no Kaigun Carrier fleet in their attack against Midway Island on December 7th. In early January 1942, they recieved artic camouflage and sailed to the Aleutians, replacing the Senjo class cruisers, which were to join the Japanese operations in Borneo. Before their departure, Aichi E13A floatplanes replaced the older Nakajima E8N.
The sixth and last unit, Kochiya, was commissioned in early 1942. Compared to her sisters, she recieved two extra triple 25mm machine gun mounts, fitted on each side of the bridge, and an anti-aircraft command post ahead of the main gun director. Her mainmast was also slightly different from that of her sisters, with a simplified rigging layout, and she was fitted with an hydrophone. She too was painted in arctic camouflage and sailed to the Aleutians.
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All six Kazamis saw little to no action for most of 1942, then in early November, they were recalled home and quickly repainted in standard grey before departing once again, this time bound for Solomon waters. The third Naval Battle of Guadalcanal was their only true shining moment, their torpedo attacks beign credited of delivering the final blow to the US Battleship New Mexico. The next three battles in which the Kazamis took part were all Carrier duels, so none of them could do more than providing anti-aircraft support to the fleet without engaging enemy ships with their guns.
In October 1943, Kazami, Kagiyama, Kawashiro and Inubashiri left the Solomons and returned to Koko. All were refitted and recieved extra machine-guns for a total of eighteen 25mm and eight 13mm machine guns, a Type21 air-search radar was added to the man-gun director and an anti-aircraft command post added. At the end of the refit, the four units were deployed once again to the Aleutians. Inubashiri was Sunk on December 19th 1943 during the Naval Battle of Unalaska.
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Onozuka and Kochiya kept operating around the Solomon Islands for the rest of 1943, taking part in every major operation against the advancing US forces. Onozuka was heavily damaged on February 9th during the battle of Manning strait, returning to Koko for repairs. Kochiya finally headed home for a much-needed refit in late June of the same year. Both ships recieved the Type13 and Type21 air-search and the Type22 surface-search radars, augmented by HA-fire control of Thiarian derivation for the 120mm guns. Light anti-aircraft armament was increased to 9 triple and 18 single 25mm machine-guns for a total of 45 barrels. The quadruple 13mm mounts were replaced, and the air intake of the boilers around the funnel were modificed in order to make space for anti-aircraft platforms, anti-aircraft command post was added above the bridge. Two depth-charge rack were added at the stern and most of the portholes were sealed over to increase waterthight integrity. Strangely and hydrophone was planned to be added but ultimately not fitted because of the need to send the ships to the Solomons as soon as possible.
Onozuka and Kochiya were back in southern waters by late July 1944, they did their part in escort and supply runs, but their partecipaton was ultimately futile in reversing the outcome of the Solomons and Bouganville campaign. Both damaged during the Raid on Rabaul they returned to Koko once again. Onozuka had suffered only slight damage so she was repaired quickly and sent to the south once again to help the evacuation of Japanese and Kokoan troops. On December 11th 1944 Onozuka was torpedoed and sunk by an American submarine. She had yet to recieve her hydropohone.
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The four surviving sisters kept operating around the Aleutians, largely achieving nothing in front of a increasingly superior US Navy other then getting repeatedly damaged. In September 1945 they recieved another major refit: the radar suite was further augmented with a mix of indigenous and Thiarian-designed radars and fire-control systems. The AA director, the forward searchlight platform and the midship machine gun directors were all raised to improve their field of operation. A third machine gun director was added on the aft superstructure. The anti-aircraft armament was augmented to a maximum of eighteen triple and 41 single 25mm machine-guns on Kazami herself, a whopping 95 barrels. All ships recieved hydrophones, depth charges, newer Aichi E16A seaplanes and a bule/black camouflage for night operations.
During the Philippine campagin the four were split. Kazami and Kagiyama Joined Kurita Center Force, while Kawashiro and Kochiya escorted Jisaburo Ozawa Carrier force. During the subsequent operations, Kazami and Kagiyama played a pivotal role when they detected a group of American Submarines during the night of october 22/23rd, spoiling a possible ambush. Under the guidance of Kagiyama Commander a group of destroyers gave chase, sinking the USS Darter and forcing the other Submarine to flee. The two cruisers survived with various extent of damage the Battle of the Sibuyan Sea, The battle off Samar and the Battle of the San Bernardino Strait. Both Kawashiro and Kochiya were isntead sunk in the late actions of the battle of cape Engano, when they deliberately charged the US surface units in order to left the rest of the fleet escape.
After the Leyte debachle, Kazami and Kagiyama suffered further damage on October 29th during an American air raid, but managed to depart Manila heading for Koko. After a brief stop in Yokosuka, on November 3rd, the two ships took the sea again. Later on, the night of november 5th 1945, Kagiyama lost contact with Kazami. Five minutes later a large explosion was sighted to starboard. Kazami had been torpedoed by the USS Tiburon (SS-529). According tot he US captain report, the Cruiser was hit by four torpedoes out of a spread of six, two put out of action the aft boiler rooms and the engines, causing a general loss of power, the other two hit forward, eventually causing the main gun magazines to explode as the ship capsized. Nor Tiburon or Kagiyama sighted or retrived any survivor of her crew of 557.
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Kagiyama, now the only ship left of her class, reached Hoshiguma harbor, Koko, the morning of November 7th. Widespread uprisings had started less than 24 hours before. Like most of Koko no Kaigun units and crews, Kagiyama joined the rebels, ultimately surrendering the the US forces when the armistice was signed in March 1946. The ship was painted in the standard US Navy Measure 22 camouflage, with her name and Kokoan flag also added on her side, and interned at Midway Atoll.
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The ship was recalled to action less than a month later for the Okinawa campaign. Her anti-aircraft suite was modified by fitting newer twin 40mm machine guns: seventeen mounts, or 34 barrels, augmented by 26 single 25mm machine guns which were left in place. Those mounts were a reverse-engineering of British Bofor mounts captured by the IJA at Singapore in early 1942, and had been under developement by Japan and koko since then. It was planned to refit Kagiyama as such since her return to koko in november 1945 with a full suite, but the uprisings and subsequent surrender halted this plan. The Kokoan flag on her side was painted over and Kagiyama joined the co-belligerent fleet. On May 25th 1946, Kagiyama was attacked and heavily damaged by Japanese Kamikazes. Two planes slammed on her starboard side, one near the bridge and the other at midship, a third Kamikaze dived vertically hitting between the bridge and the funnel. The three hits killed most of the bridge crew and knocked all boilers and one turbine out of action, starting fires and almost sinking the ship. After recieving temporary repairs, Kagiyama sailed back to Koko to start major, more comprehensive, repairs, but the damage accumulated at Okinawa led the ship to be declared a constructive total loss.
Kagiyama was definitely decommissioned on September 21st 1946, her scrappping beginning almost immediately.

Ships in class: (laid down-launched-commissioned - fate)

Kazami 1936-1937-1938 - Sunk 1945
Onozuka 1937-1938-1938 - Sunk 1944
Kagiyama 1937-1938-1939 - Decommissioned 1946
Kawashiro 1938-1940-1940 - Sunk 1945
Inubashiri 1939-1940-1941 - Sunk 1943
Kochiya 1940-1941-1942 - Sunk 1945

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