Landing craft carriers orlanding craft depot ships were an innovative type ofamphibious warfare ship developed by theImperial Japanese Army duringWorld War II. The prototype was developed in secrecy under thepseudonymsRyujo Maru andFuso Maru[1] using features later adopted by other navies fordock landing ships andamphibious transport docks. Additional ships were built after combat experience validated the concept, but most were completed after theJapanese invasions of the early war, and used primarily astroopships during later operations. Today'samphibious assault ships bear a strong similarity to this concept.
Shinshū Maru was completed in 1935 and modified in 1936 to include a floodablewell dock. She was the world's first ship specifically designed to carry and launchlanding craft.[1] She introducedstern and side gates to launch landing craft for the 2,200 soldiers she carried. She demonstrated the advantages of the concept at the invasions ofShanghai,Malaya andJava.[2]
Hei-type landing craft carriers included aflight deck with a capacity for 28 aircraft, but nohangar deck, since the deck beneath the flight deck was used to carry 25 landing craft launched through stern doors.[3]Akisu Maru was completed in time to participate in the invasion of Java; but she and the other Hei-types were thereafter used primarily as ferries to transport short-range aircraft to distant bases. The first two were completed from 11,800-ton, 20knots (37 km/h; 23 mph) Nippon Kaiun, K. K.passenger ships under construction by Harima Shipbuilding. They operated twoKayaba Ka-1autogyros.[2] Both were sunk by submarines in 1944.[1]
The others were based onHitachi Shipbuilding Corporation's standard 8,000-ton, 19 knots (35 km/h; 22 mph) Type-M cargo steam ship modified (Type-MC)[1] to carry twelveToku Daihatsu-class landing craft launched through stern doors[2] with funnels installed horizontally on the starboard side to accommodate a flight deck.[1]
The larger type were 11,910-ton, 20.8 knots (38.5 km/h; 23.9 mph) diesel-engined ships fitted with stern ramp gates for launching twentyDaihatsu-class landing craft stored in floodableholds. At the time, this launching method was unprecedented. Both were sunk by submarines with very heavy loss of life.[2]
Later production was Hitachi's standard Type-M steam ship modified (Type-MA) to carry twelve Toku-Daihatsu-class landing craft.[2] The landing craft were launched from rails which ran along the main deck (between port and starboardfunnels for those carried forward of thesuperstructure) down to thewaterline through large hinged doors at the stern.Settsu Maru survived for use as a repatriation ship, but her sister ships were sunk in air raids on Japanese ports.[1]
Takatsu Maru was a 5,656-ton, 19-knot steam ship[2] completed in January 1944 withicebreaker capability,[3] and used conventional cranes rather than gates for handling nine Toku-Daihatsu-class landing craft.[2] She was sunk by United States aircraft inOrmoc Bay during theinvasion of the Philippines.[1]