Japanese Cruiser Chōkai

was a heavy cruiser, armed with ten guns, four guns, eight tubes for the Type 93 torpedo, and assorted anti-aircraft guns. Named for Mount Chōkai, ''Chōkai'' was designed with the Imperial Japanese Navy strategy of the great "Decisive Battle" in mind, and built in 1932 by Mitsubishi's shipyard in Nagasaki.

''Chōkai'' participated in numerous actions during the Pacific War including the Battle of Savo Island off Guadalcanal, in which she, along with other Japanese cruisers, sank the heavy cruisers , and . She was sunk in the Battle off Samar in October 1944.

Design

The ''Takao''-class cruisers were an improved version of the previous design, incorporating technical elements learned with the development of the experimental light cruiser . They had a distinctive profile with a large, raked main smokestack, and a smaller, straight, second smokestack. Intended to address issues with the ''Myōkō '' class, the ''Takao'' class had thicker armor, dual-purpose main guns which could be used against aircraft, and torpedo launchers moved to the upper deck for greater safety. However, as with its predecessors, the ''Takao'' class was also top-heavy.Patton, ''Japanese Heavy Cruisers of World War Two'', pp. 36–48

The ''Takao'' class displaced . ''Chōkai'' was long, with a beam of , draft of and was capable of 35.25 knots.

Propulsion was by 12 Kampon boilers driving four sets of single-impulse geared turbine engines, with four shafts turning three-bladed propellers. The ship was armored with a side belt, and armored deck;, the bridge was armored with armored plates.

''Chōkais main battery was ten 20 cm/50 3rd Year Type naval guns, the heaviest armament of any heavy cruiser in the world at the time, mounted in five twin turrets. Her secondary armament included four Type 10 12 cm dual purpose guns with four single mounts, two on each side, and 8 Type 90 torpedoes in four twin launchers, with 16 as reloads. She was very deficient in anti-aircraft capability, with only two anti-aircraft guns and two 7.7 mm machine guns. Her last refit removed the two 40 mm and 7.7 mm anti-aircraft guns in exchange for a total of 38 Type 96 in four twin and 22 single mounts. Her torpedoes were upgraded to the more powerful Type 93 torpedoes. Uniquely to ''Chōkai'', she did not receive the extensive refit her sisters did, keeping the 12 cm guns and four twin torpedo tubes, whereas her sisters received the Type 89 and four quad torpedo tubes.

Operational history

At the start of the Pacific War, ''Chōkai'' supported the invasion of Malaya and participated in the pursuit of the Royal Navy's battleship Force Z. During January and February 1942, ''Chōkai'' was involved in operations to seize the oil-rich Dutch East Indies and the island of Borneo. Steaming near Cape St. Jacques, ''Chōkai'' struck a reef, sustaining hull damage on 22 February 1942. On 27 February, she reached Singapore for repairs.

After repairs, ''Chōkai'' was once again assigned to a support role in an invasion, this time the landings at Iri, Sumatra, and the invasion of the Andaman Islands and the seizure of Port Blair a few days later. Afterwards, ''Chōkai'' sailed to Mergui, Burma.

On 1 April 1942, ''Chōkai'' left Mergui to participate a raid on merchant shipping in the Bay of Bengal. First, ''Chōkai'' torpedoed and sank the U.S. freighter ''Bienville'', and later on, the British steamship ''Ganges'' on 6 April. With her role in the operation successfully concluded, ''Chōkai'' returned to Yokosuka on 22 April 1942.

Battle of Savo Island

By mid-July 1942, ''Chōkai'' was made the new flagship of Vice Admiral Mikawa Gunichi and his 8th Fleet. She proceeded towards Rabaul. On 7 August 1942, with Guadalcanal having been invaded by the Americans, ''Chōkai'' headed for the Guadalcanal waters, with Vice Admiral Mikawa aboard. In the battle of Savo Island, Mikawa's squadron of heavy cruisers, consisting of ''Chokai'' herself, and the heavy cruisers ''Furutaka,'' ''Kako'', ''Aoba'', and ''Kinugasa'' inflicted a devastating defeat on an Allied cruiser squadron. First, ''Chōkai'' and ''Aoba'' targeted the Australian heavy cruiser ''Canberra'', followed by ''Furutaka'' and ''Kako'' joining in, and all four ships sank ''Canberra'' with gunfire. Following that, ''Chōkai'' pounded the heavy cruiser , and as ''Aoba'', ''Kako'', and ''Kinugasa j''oined in, ''Astoria'' sank. Finally, while other cruisers lit the cruiser aflame and sank her, ''Chōkai'' sank the heavy cruiser with two hits from her long lance torpedoes. The battle of Savo Island was one of the most devastating Japanese naval victories of the war, the four allied heavy cruisers sunk and several more ships damaged or crippled. However, ''Chōkai'' sustained several hits from ''Quincy'' and ''Astoria'', disabling her "A" turret and killing 34 men. ''Chōkai'' returned to Rabaul for temporary repairs. For the rest of the Solomon Islands campaign, ''Chōkai'' would fight in an assortment of night battles with the U.S. Navy, sustaining varied, but mostly minor, damage.

Subsequent action

Relieved as the Eighth Fleet flagship shortly after the final evacuation of Guadalcanal, ''Chōkai'' headed back to Yokosuka on 20 February 1943. Tasked with various minor duties for the remainder of 1943 and first half of 1944, ''Chōkai'' was made the flagship of the Cruiser Division Four ("CruDiv 4") comprising , , , and ''Chōkai'' on 3 August 1944. All four ships took part in the Battle of the Philippine Sea.

Battle of Leyte Gulf

CruDiv 4 was part of Admiral Takeo Kurita's large fleet of IJN battleships, cruisers, and destroyers that took part in the various engagements of the Battle of Leyte Gulf at the Philippines.

CruDiv 4 suffered a harrowing submarine attack on 23 October 1944, with the sinking of and (which was Kurita's flagship, though he survived), while was left permanently crippled, leaving ''Chōkai'' as the only undamaged ship of CruDiv 4.

''Chōkai'' was then transferred to Cruiser Division Five, where she survived an air attack on 24 October 1944, while the battleship '' Musashi'' was sunk.

Sunk in the battle off Samar

On the morning of 25 October, ''Chōkai'' engaged an American force of escort carriers, destroyers, and destroyer escorts in the Battle off Samar. During her approach to the US escort carriers, ''Chōkai'' was hit several times on the port side amidships by 5"/38 caliber guns of this force's escort carriers and destroyers. It was believed at the time that one of these hits may have set off the eight deck-mounted Japanese Type 93 "Long Lance" torpedoes; however, 's expedition in 2019 found ''Chōkai''s torpedoes still intact. An explosion was observed aboard ''Chōkai'' before a TBM Avenger from the '' USS Kitkun Bay'' dropped a 500 lb (230 kg) bomb on her forward machinery room. Fires began to rage and she went dead in the water. She was scuttled later that day by torpedoes from the destroyer (), which also rescued some of her crew. Two days later ''Fujinami'' was sunk with the loss of all hands, including the ''Chōkai'' survivors.

Wreck

''Chōkai'' sits upright in of water on the edge of the Philippine Deep. RV ''Petrel'' discovered the wreck of ''Chōkai'' on 5 May 2019 and dived it via ROV on 30 May 2019.

References

Bibliography

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{{DEFAULTSORT:Chokai
Takao-class cruisers
Ships built by Mitsubishi Heavy Industries
1932 ships
World War II cruisers of Japan
Scuttled vessels
Warships lost in combat with all hands
World War II shipwrecks in the Philippine Sea
Maritime incidents in October 1944
2019 archaeological discoveries
Shipwreck discoveries by Paul Allen