Japanese aircraft carrier Ryūhō

	Ryūhō in 1942
History
Empire of Japan
Name	Taigei
Operator	Imperial Japanese Navy
Builder	Yokosuka Naval Arsenal
Laid down	12 April 1933
Launched	16 November 1933
Completed	31 March 1934
Out of service	12 December 1941
Renamed	30 November 1942
Fate	Converted into a light aircraft carrier
Name	Ryūhō
Namesake	Japanese for Dragon Phoenix
Recommissioned	30 November 1942
Stricken	30 November 1945
Fate	Scrapped, 1946
General characteristics
Type	Light aircraft carrier
Displacement	16,700 standard displacement)
Length	215.65 m (707 ft 6 in) (o/a)
Beam	19.58 m (64 ft 3 in)
Draft	6.67 m (21 ft 11 in)
Installed power	4 Kampon water-tube boilers; 52,000 kW);
Propulsion	2 shafts; 2 geared steam turbine sets
Speed	26.5 knots (49.1 km/h; 30.5 mph) (design)
Range	8,000 nmi (15,000 km; 9,200 mi) at 18 knots (33 km/h; 21 mph)
Complement	989
Sensors and ; processing systems	1 × Type 2, Mark 2, Model 1 air search radar
Armament	(in 1942) 4 × twin 12.7 cm DP guns; 10 × triple 25 mm AA guns; 6 depth charges; (in 1945); 4 × twin 12.7 cm DP guns; 10 × triple, 4 × twin, 23 × single 25 mm AA guns; 6 × single 13 mm AA guns; 6 depth charges; 6 × 12 cm rocket launchers;
Aircraft carried	31–36

Ryūhō (龍鳳, "Dragon phoenix") was a light aircraft carrier of the Imperial Japanese Navy. She was converted from the submarine tender Taigei (大鯨, "Big Whale"), which had been used in the Second Sino-Japanese War. One of the least successful of the light aircraft carrier conversions due to her small size, slow speed and weak construction, during World War II, Ryūhō was used primarily as an aircraft transport and for training purposes, although she was also involved in a number of combat missions, including the Battle of the Philippine Sea.

Background

The

fleet oilers and submarine tenders, designed so that they could be converted quickly into aircraft carriers in time of conflict. Taigei was ordered as part of the 1st Naval Armaments Supplement Programme

of 1932.

Design

Although Taigei was designed from the onset for possible later conversion to an aircraft carrier, the design proved to have many shortcomings. The basic design of the hull suffered from a high freeboard with a shallow draught, which resulted in poor stability. Although extensive use of electric arc welding on the hull speeded construction time and was considered highly innovative for the time, lack of experience with this technique led to many weak welds, and the ship suffered from frequent cracks. Inadequate sectioning into waterproof compartments below her waterline, combined with the weak construction of her hull, also made the ship vulnerable in combat situations.^[1] The new vessel was also plagued by the poor performance of its diesel engines, which gave only half the output expected.

Conversion of Taigei into an aircraft carrier entailed adding a 185-by-23-metre (607 by 75 ft) flight deck. Two 13.6-by-12.0-metre (44.6 by 39.4 ft) elevators connected the flight deck to the hangar deck below. During the conversion, the problematic diesel engines were replaced by

Mitsubishi A6M "Zero" fighters, Aichi D3A "Val" and Yokosuka D4Y "Judy" dive bombers, and Nakajima B5N "Kate" torpedo bombers

, but her small size limited her usefulness in combat operations. In August 1944, her flight deck was lengthened to 198.1 meters, but the number of aircraft embarked could only be increased to 36.

Operational history

As the submarine tender Taigei

Taigei was

Emperor Hirohito attend the launching ceremony and due to inexperience with the electric arc welding method, portions of the hull warped during construction. Immediately after the launching ceremony, Taigei was returned to the dry dock

for repairs and modifications, which involved replacement of damaged sections by the traditional rivet construction method.

Formally commissioned on 31 March 1934, Taigei was soon damaged by a

February 26 Incident. It was not until September 1938 that Taigei was deemed fully operational, and assigned to its design role as flagship

of a submarine squadron.

From 1938 to 1940, Taigei performed normal operations in both northern and southern waters off Japan, with her primary mission being to support submarine operations off the coast of China from her home port of Kure in the Second Sino-Japanese War. She was reassigned from the 1st Fleet to the 6th Fleet on 15 November 1940 and was based at Kwajalein Atoll from 10 April 1941. Shortly before the start of hostilities in the Pacific War, Taigei was ordered back to Japan for conversion into a light aircraft carrier, arriving at Kure on 4 December.

The conversion work began on 20 December at Yokosuka Naval Arsenal, and was originally scheduled to be completed within three months; however, numerous problems and issues arose, and the conversion work was not completed until 30 November 1942. She gained the distinction of being the only major warship damaged in the

incendiary bomb hits, with seven casualties among her crew.^[2]

As an aircraft carrier, the vessel was renamed Ryūhō.

As the aircraft carrier Ryūhō

On 30 November 1942, with conversion and repairs complete, Ryūhō was officially assigned to the

Hachijojima, and was immediately forced to return to Yokosuka for emergency repairs, and remained out of operation until early 1943.^[2]

On 19 March Ryūhō began a series of uneventful aircraft ferry missions to occupied islands in the South Pacific. On 11 June, Ryūhō embarked the marooned survivors of the air group of

3rd Fleet, accompanying the escort carriers Unyō and Chūyō to Truk and back, and remaining based in the Seto Inland Sea for training missions.^[2]

In October, Ryūhō was sent on another aircraft ferry mission to

Tarakan, then Palau, then Truk, then Saipan, and finally returning to Kure on 2 January 1944.^[2]

After two more uneventful patrol and training missions between Japan and the

F6F Hellcat fighters and the anti-aircraft guns of the American fleet. On 20 June, Ryūhō was attacked by four Grumman TBF Avenger torpedo bombers from the aircraft carrier USS Enterprise. She suffered only slight damage from near misses.^[2]

Ryūhō engaged in several more patrol and training missions near Japan. On 25 October, with the escort carrier Kaiyō, Ryūhō set sail from Sasebo Naval District on another aircraft ferry mission to Keelung, Taiwan. They were escorted by the destroyers Momi, Ume and Momo. They returned to Kure on 2 November. From 7 to 15 November, Ryūhō briefly flew the flag of the Commander of the Mobile Fleet, Admiral Jisaburō Ozawa.^[2]

Final mission

On 31 December 1944, Ryūhō sailed for Taiwan with a load of 58

Ohka kamikaze planes. Accompanying her were nine empty oil tankers bound for Singapore, and the destroyers Hamakaze, Isokaze, Yukikaze, Shigure and Hatakaze.^[2]

Upon reaching Taiwan and unloading her cargo, Ryūhō was among the targets of a major series of American carrier-based air raids all over the island. Twelve TBF Avengers attacked her, but none scored a hit, and Ryūhō's gunners shot down one of them. Ryūhō departed for Japan on 2 January 1945 escorted by Isokaze; when she arrived at Kure on 18 January, Ryūhō also gained the distinction of being the last Japanese aircraft carrier to venture outside the home waters of Japan.[2]

Ryūhō was attacked by

navy list on 30 November 1945^[2]

and scrapped in 1946.