was the third and final of the Imperial Japanese Navy built during World War II. Named after Mount Katsuragi, in Nara Prefecture, and completed late in the war; she never embarked her complement of aircraft and spent the war in Japanese waters. The ship was badly damaged in a July 1945 airstrike by American carrier aircraft on Kure Naval Base. Repaired after the end of the war, Katsuragi was then used as a repatriation transport for a number of months, bringing Japanese soldiers and civilians back to Japan from overseas locations. She was scrapped in Japan beginning in late 1946.
Design and description
The last purpose-built Japanese carrier construction during World War II was a group of vessels based on an improved design, but with individual units differing in detail reflecting the changing circumstances as the conflict in the Pacific approached its conclusion. Katsuragi was ordered 25 June 1942, under the provisional name of #5003, as part of the Kai-Maru 5 Program of 1942. This was a massive naval construction program intended to replace losses suffered at the Battle of Midway and focused on aircraft and aircraft carriers. The ship was one of 16 s planned, although only three were completed before the end of the war.
Katsuragi had the same hull design as . She had a length of overall. She had a beam of and, at deep load, a draft of . She displaced at deep load. Her crew consisted of 1,576 officers and men. When acting as a flagship she had a total of 1,600 crewmembers.
A shortage of turbines and boilers led to machinery of the same type as that used in the being used in Katsuragi. These consisted of four geared steam turbine sets with a total of driving four shafts, each fitted with a propeller. Steam was provided by eight Kampon Type B water-tube boilers with a working pressure of at . The ship had a designed speed of , but during sea trials on 12 October 1944, she reached at the light displacement of . Katsuragi carried of fuel oil although no data on her range is known. She had two funnels on the starboard side, each angled below horizontal. They were fitted with a water-cooling system to reduce the turbulence caused by hot exhaust gases.
Flight deck arrangements
Katsuragis flight deck was long and had a maximum width of . A small island was mounted well forward on the starboard side and contained the ship's bridge and air operations control center. It was fitted with a small tripod mast that mounted one of the ship's radar antennas. The ship was designed with two superimposed hangars that were served by two aircraft elevators, each ; the center elevator as used in Hiryū was deleted to simplify construction and reduce stress in the hull. The elevators had a maximum capacity of and took 19 seconds to go from the lower hangar to the flight deck. Katsuragi was fitted with hydraulically operated Type 3 arresting gear with nine cables. She also mounted three Type 3 crash barricades. No aircraft catapult was fitted. The ship mounted a retractable crane on the starboard side of the flight deck, just aft of the rear elevator.
The ship's air group was originally intended to consist of 12 Mitsubishi A6M Zero fighters, plus three in storage, 27 Aichi D3A Val dive bombers, plus three in reserve, and 18 Nakajima B5N "Kate" torpedo bombers (plus two in crates). Katsuragis hangars could not accommodate so many aircraft so eleven planes were planned to be permanently carried on the flight deck. In 1943 the air group was revised to consist of 18 Mitsubishi A7M "Sam" fighters (+2 in storage), 27 Yokosuka D4Y "Judy" dive bombers and six Nakajima C6N "Myrt" reconnaissance aircraft. Of these, the C6Ns were intended to be carried on the flight deck. When the ship commissioned in 1944, neither the A7M nor the C6Ns were yet in service, so the air group was reconfigured to consist of 27 Zeros, 12 D4Ys, three of which were to be the reconnaissance version, and nine Nakajima B6N "Jill" torpedo bombers. By this time, however, the shortage of carrier-qualified aircrew was such that they were ordered to operate from shore bases and Katsuragi never embarked her air group. Katsuragi carried of aviation gasoline for her aircraft.