was an aircraft carrier of the Imperial Japanese Navy during World War II. Possessing heavy belt armor and featuring an armored flight deck (a first for any Japanese aircraft carrier), she represented a major departure from prior Japanese aircraft carrier design and was expected to not only survive multiple bomb, torpedo, or shell hits, but also continue fighting effectively afterwards.
Built by Kawasaki at Kobe, she was laid down on 10 July 1941, launched almost two years later on 7 April 1943 and finally commissioned on 7 March 1944. She sank on 19 June 1944 during the Battle of the Philippine Sea due to explosions resulting from design flaws and poor damage control after suffering a single torpedo hit from the American submarine USS Albacore.
Design
Taihō was approved for construction in the 1939 4th Supplementary Programme. Her design was that of a modified . Under the Modified Fleet Replenishment Program of 1942, Taihō was to be the first of a new generation of Japanese aircraft carriers, which would include Taihō, 15 of a modified design (which turned into the ) and five of an improved Taihō design (G-15 Project).
Hull
Taihōs waterline belt armor varied between abreast the machinery to around the magazines. The armor below the waterline was designed to withstand a charge.
The weight of Taihōs armor immersed her hull so deeply that her lower hangar deck was barely above the load waterline and the bottoms of her two elevator wells (which formed the roofs of her fore and aft aviation fuel tanks) were actually below the waterline. This latter fact played an important role in her subsequent destruction during the Battle of the Philippine Sea.
Taihōs aviation fuel tanks were only partially protected with armor, as naval designers opted earlier to devote greater protection to their carriers' bomb and torpedo magazines. The empty air spaces around the aviation fuel tanks turned out to be the ship's downfall; all subsequent Japanese carriers had theirs filled with concrete to protect against splinters and shock damage, although it was poor damage control that ultimately sank Taihō.
To improve seakeeping and airflow over the forward end of the deck, Taihōs bow was plated up to flight deck level, giving her a similar appearance to British s.
Machinery
Taihōs eight oil-fired Kampon RO-GO boilers were capable of generating . Her four Kampon steam turbines were each geared to separate propeller shafts. She had a top speed of . Taihōs maximum fuel oil storage of gave her a radius of at .
Taihō had two rudders positioned along the longitudinal center-line of the ship: a semi-balanced main rudder (so-called because a portion of the rudder comes before the hinged axis and therefore requires less force to turn) located astern and an unbalanced auxiliary rudder forward of the main rudder. Both were turned via electro-hydraulically powered steering gears, but the auxiliary rudder could also be turned via a diesel engine in the event the primary steering gear was damaged.
Flight deck
Taihō was the first Japanese aircraft carrier to feature an armored flight deck, designed to withstand multiple bomb hits with minimal damage. The armor varied slightly in thickness between and formed a protective lid over an enclosed upper hangar whose sides and ends were unarmored. The floor of the upper hangar was also unarmored but the lower hangar deck had plating. Taihōs flight deck, measuring long and wide, had the largest total area of any Japanese carrier until the completion of and was offset to port to compensate for the weight of her island structure. Unlike all pre-war Japanese carriers, Taihōs flight deck was not wooden-planked. Rather, the steel deck was covered with a newly developed latex coating approximately thick. This offered several advantages over wood: it was cheaper, it saved weight, it required fewer man-hours to apply and it was less likely to interfere with air operations in the event of minor damage. On the negative side, the material had only mediocre anti-skid qualities and tended to become brittle and crack over time.