The Akitsushima-class seaplane tender was a class of two 4,700 ton seaplane tenders that entered service in 1942 and 1943 respectively.
In 1938, the IJN wanted to use their large-sized flying boats more effectively, because the Kawanishi H6K was the only aircraft able to hit Pearl Harbor directly from the Marshall Islands. However, the Marshall Islands did not have flying boat facilities at that time. Early in 1939, the IJN converted the oiler Kamoi to a seaplane tender. However, she was not able to repair seaplanes.
The IJN therefore planned two kinds of seaplane tenders which were included in the Maru 4 Programme. One was a 10,000 tons class flying boat carrier, the other a 2,400 tons class flying boat tender. These plans were not able to pass the assessment by the Ministry of Finance. These two basic plans were revived by the Maru 5 Programme in 1941. However, their construction did not begin. Therefore the IJN planned a 3,500 tons class tender, which was a scaled-up model of the 2,400 tons class. The ships should be able to maintain, repair and supply seaplanes. The IJN intended to accommodate the flying boat by bow-up trim and slope at first, however this plan was cancelled and the Akitsushima-class was equipped with a 35-ton crane. The IJN changed the design frequently, ending up with a displacement increased by 1000 tons.
- IJN Akitsushima
- IJN Chihaya