Taiyo Class aircraft carriers

The three ships in the Taiyo class of aircraft carriers were part of the Imperial Japanese Navy’s shadow carrier programme, and had originally been laid down as passenger liners. The three ships of the Nitta Maru class of liners were funded in 1937, and were designed to allow them to be easily converted into carriers.

Taiyo from above
Taiyo from above

The Nitta Maru and Yawata Maru were actually completed as liners and were then requisitioned. They were then converted into the carriers Chuyo (completed November 1942) and Unyo (completed May 1942). These two carriers could carry 30 aircraft. They were armed with Type 89 mountings for 25mm guns, originally carrying eight guns. By the time they were sunk the Chuyo was carrying fourteen guns and the Unyo a massive 64.

The final liner, the Kasuga Maru was requisitioned while still under construction, and was completed as the carrier Taiyo in September 1941. Despite having been taken over at an earlier stage in construction, she could only operate 23 aircraft with four in reserve. When completed the Taiyo was armed with six 4.7in and four twin 25mm antiaircraft guns. In 1943 she was given more 25mm guns and in 1944 the 4.7in guns were removed and she too ended up with 64 25mm guns.

All three ships were flush-deck carriers, with one hanger and two elevators. Their civilian diesel engines were replaced by turbines, but without the hoped for increase in speed.

Plan of Taiyo class carrier
Plan of Taiyo class carrier

It had been hoped that these carriers would be able to work with the Combined Fleet, but they proved to be too slow for front line service. The Taiyo was the only one to see front line service, working alongside the battleship Yamato off Guadalcanal in August 1942. Instead they were used to ferry aircraft, supplies and passengers around the greatly expanded Japanese Empire.

The Chuyo was lost while performing this duty. Between December 1942 and December 1942 she carried out thirteen supply runs, and was torpedoed three times by US submarines. On 4 December 1943 she was hit for the third time, by USS Sailfish, and sank quickly with the loss of 1,250 lives.

The surviving ships were transferred to the newly formed Grand Escort Command in December 1943, a belated reaction to the devastating US campaign against Japanese shipping. They were sunk within a month of each other in the second half of 1944. The Taiyo was torpedoed by USS Rasher on 18 August, her aviation fuel tanks exploded, and less than 100 of her crew survived. The Unyo was hit and sunk by two torpedoes from USS Barb on 18 August 1944.

Displacement (standard)


Displacement (loaded)


Top Speed







591ft 4in max


8 5in/40 dual purpose guns  (6 4.7/44 AA on Taiyo)
8 25mm antiaircraft guns

Crew complement

850 (747 Taiyo)

Ships in class

Taiyo (Great Hawk)
Unyo (A Hawk in the Clouds)
Chuyo (Heaven-bound Hawk)

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How to cite this article: Rickard, J (27 November 2008), Taiyo Class aircraft carriers, http://www.historyofwar.org/articles/weapons_taiyo_class.html

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