No.1-class landing ship

The No.1 class landing ship (第一号型輸送艦,) was a class of amphibious assault ships of the Imperial Japanese Navy (IJN), serving during and after World War II. The IJN also called them 1st class transporter (一等輸送艦,).

Background

 * The IJN lost too many destroyers while employed as transporters ("Tokyo Express") in the Guadalcanal Campaign.
 * Therefore, the IJN wanted the enforced transporter which could penetrate the front line. It was realized rapidly after Operation Ke.

Design

 * In April 1943, the General Staff requested a high-speed military transporter to the Technical Department. The requirements were as follows:
 * Displacement: 1250 LT standard
 * Propulsion: 1 × geared turbine, 2 × boilers, single shaft
 * Speed: 23 kn
 * Range: 3500 nmi at 18 kn
 * Capacity: 2 × Landing craft (Daihatsu) and 200 tons freight
 * Armament: 2 × 127 mm or 120 mm AA guns, 9 × 25 mm AA guns and 36 × depth charges
 * The General Staff thought it was possible to use a variant of the Matsu class destroyer for this plan, because they aimed to achieve the mass production effects. In this original plan, the equipment of a slope was not considered. They thought about a Japanese version of the High speed transport (APD).
 * The Technical Department, however, did not agree to this plan. They submitted a more aggressive plan to the General Staff. They increased the number of landing craft carried and planned to reduce time for the landing.
 * In addition, about the mass production effect, they intended to deal with this by reducing the shipyards.
 * At that time, the stern slope and operative ability of the amphibious tanks were added.
 * In September 1943, the Kure Naval Arsenal finished the detailed design. Her project number was J37.

Construction

 * The IJN nominated Kure Naval Arsenal as the main builder and Mitsubishi Heavy Industries as support builder.
 * Lead ship (Landing ship No.1) was constructed at Mitsubishi, laid down on 5 November 1943, launched on 8 February 1944, and completed on 10 May 1944.
 * The Kure Naval Arsenal completed 15 vessels, Mitsubishi completed 6 vessels.
 * The Kure Naval Arsenal was earnest. They made the original sized wooden samples, and learned a work procedure. And, they used the Yamato's dock and repeated built 2 vessels at the same time. Therefore most Kure's vessels were completed within 80 days from laid down.
 * The completed vessels were spent one by one to the front.

Service

 * Their primary role was that of a transporter, however since their armaments were strong they were useful as multi-purpose ships at the front, functioning as transporters, as minelayers and as escort ships.
 * Most of these vessels were sent to the Battle of Leyte and transportation duty of the Bonin Islands. By that time, the IJN already lost air superiority and thalassocracy in those areas and these vessels suffered heavy losses.
 * 5 vessels survived war and were surrendered to the Allies.