Type D escort ship

The Type D escort ships (丁型海防艦, Tei-gata kaibōkan) were a class of escort ships in the service of the Imperial Japanese Navy during World War II. The Japanese called them "Type D" coast defence ships, and they were the sixth class of Kaibōkan (Kai = sea, ocean, Bo = defence, Kan = ship), a name used to denote a multi-purpose vessel. 143 ships were ordered under the 1943–44 Programme, and a further 57 units were planned (but never ordered) under the 1944–45 Programme, for an overall total of 200 ships. However, only 67 were completed, with the remainder being cancelled.

Background

The Type D, like the Ukuru and Mikura classes, were dedicated to the anti-aircraft (AA) and anti-submarine role.

On 22 April 1943, the Navy General Staff decided a mass production of escort ships, because of the urgent need to protect the convoys which were under constant attack. The plan was to build a basic escort ship of around 800 tons, with a simple design for easy construction.

The first designs, for "Type A" Etorofu class and "Type B" Mikura class, still needed too many man-hours for building, so in June 1943, the Navy General Staff planned for a simplified design. The result was the Ukuru class, and a scaled-down model of the Mikura class, which became the "Type C" (with diesel engines driving twin screws) and "Type D" (with turbine engines driving a single screw) escort classes.

Design

Because of Japan's deteriorating war situation, the Type D version was a further simplification of the Ukuru design and were built to the same design as the Type C escort ship. However, due to a shortage of diesel engines to power both groups of vessels, the Type D were powered by a single steam turbine.