# 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. This gave a slight increase in speed, from 16.5 knots (30.6 km/h; 19.0 mph) to 17.5 knots (32.4 km/h; 20.1 mph), but a reduction in range and endurance, 4,500 nautical miles (8,300 km; 5,200 mi) at 16 knots (30 km/h; 18 mph) instead of 6,500 nautical miles (12,000 km; 7,500 mi). The Type D was the only Kaibōkan type to use turbines.
They were smaller by 200 tons than the Ukuru's and engines that propelled them were also smaller, at 2,500 shaft horsepower (1,900 kW) versus 4,200 shp (3,100 kW) for the Ukurus. Because of the decrease in engine power, the speed fell from 19.5 knots (36.1 km/h; 22.4 mph) to 17.5 knots (32.4 km/h; 20.1 mph). The number of 4.7 in (119 mm) guns went from three to two. The number of depth charges aboard was the same, 120, but the number of depth charge throwers was decreased from 18 to 12 and the depth charge chutes were decreased from two to one.
Due to the simplifications of the design, a significant saving was made in construction time. The Type D escorts required approximately 20,000 man-hours each, compared to the 35,000 man-hours of the Ukurus and the 57,000 man-hours of the Mikuras.

## Construction

The design work for the Type D ships started in March 1943, at the same time as for the Ukuru class. They were built concurrently with the Ukuru class and Type C vessels. The Type D were given even number designations while the Type C were given odd numbers. The Type D were constructed using prefabricated sections that enabled them to be built in as little as three to four months. The lead ship, No.2 (CD-2) was constructed at Yokosuka Naval Arsenal, laid down on 5 October 1943, launched on 30 December 1943, and completed on 28 February 1944. CD-198 was the fastest build, being constructed in only 71 days; she was laid down on 31 December 1944, and completed on 11 March 1945. CD-204 was the last of the class being laid down on 27 February 1945 at the Nagasaki shipyard of Mitsubishi Heavy Industries, launched on 14 April 1945, and completed on 11 July 1945.

## Service

Most of the Type D escorts were assigned to the Escort Fleet. However, they were not able to stop the American submarine offensive. One drawback was they did not have an effective fire-control system. They were equipped only with one height rangefinder for the AA guns and were powerless against an air attack. Despite being simple to construct they proved themselves very durable for their size. Of the 22 instances of torpedoes striking them, they survived 9 times, with CD-30 being struck and surviving on two separate occasions. Of the seven occasions when they struck mines, only one sank. During the war 68 ships were finished out of the 200 planned; 25 were sunk during the war.

## Successes

* USS Harder was sunk on 24 August 1944 by CD-22.
* USS Scamp was probably sunk on 11 November 1944 by CD-4.
* USS Swordfish may also have been sunk by CD-4 on 4 January 1945, though evidence is unclear.
* USS Snook was probably sunk by CD-8, CD-32, and CD-52 with Okinawa on 9 April 1945.
* USS Bonefish was sunk on 19 June 1945 by CD-158 with CD-63, CD-75 and CD-207 and Okinawa.
* USS Salmon was rendered unfit for further service by damage from CD-22 with CD-33 and CD-29 on 30 October 1944.
* USS Halibut was rendered unfit for further service by damage from CD-6 on 14 November 1944.
* USS Escolar was probably sunk by CD-38 which reported having contact with and sinking a US Navy submarine on 19 October 1944 near Escolar's expected position. Escolar was never heard from again.

## Ships in class

Under the Wartime Naval Armaments Supplement Programme, it was proposed to build 300 Type C and 200 Type D escorts. These were assigned the Programme numbers #2401-#2700 for the Type C vessels, with #2701-#2900 for the Type D vessels. In view of the vast number intended, no names were allocated, but only numbers; odd numbers from No.1 upwards were assigned to Type C escorts, while even numbers from No.2 upwards were assigned to Type D escorts.
The first 143 of the Type D escorts were authorised under the 1943 Fiscal Year, but just 66 were completed and the others cancelled. The remaining 57 Type D vessels were intended to be built under the 1944 Fiscal Year, but no contracts were ever issued.
| Ship # | Ship | Builder | Laid down | Launched | Completed | Fate |
| #2701 | No.2 (第2号海防艦,, Dai 2 Gō Kaibōkan) the same shall apply hereinafter | Yokosuka Naval Arsenal | 5 October 1943 | 30 December 1943 | 28 February 1944 | Decommissioned on 20 September 1945. Scrapped on 20 July 1948. |
| #2702 | No.4 | Yokosuka Naval Arsenal | 5 October 1943 | 30 December 1943 | 7 March 1944 | Sunk by Royal Navy aircraft at Toba, 28 July 1945. Salvaged and scrapped on 30 June 1948. |
| #2703 | No.6 | Yokosuka Naval Arsenal | 5 October 1943 | 15 January 1944 | 15 March 1944 | Sunk by USS Atule at south of Hidaka, 13 August 1945. |
| #2704 | No.8 | Mitsubishi, Nagasaki Shipyard | 20 October 1943 | 11 January 1944 | 29 February 1944 | Decommissioned on 5 October 1945. Surrendered to United Kingdom, 16 July 1947. Later scrapped. |
| #2705 | No.10 | Mitsubishi, Nagasaki Shipyard | 20 October 1943 | 11 January 1944 | 29 February 1944 | Sunk by USS Plaice at west of Tokara Islands, 27 September 1944. |
| #2706 | No.12 | Yokosuka Naval Arsenal | 5 October 1943 | 15 January 1944 | 22 March 1944 | Decommissioned on 30 November 1945. Surrendered to United States, 5 September 1947. Scrapped on 30 November 1947. |
| #2707 | No.14 | Yokosuka Naval Arsenal | 5 October 1943 | 25 January 1944 | 27 March 1944 | Decommissioned on 30 November 1945. Surrendered to Republic of China 6 July 1947, and renamed Tsinan. Captured by People's Liberation Army 1949, and renamed Wuchang (215). Decommissioned in 1982. |
| #2708 | No.16 | Yokosuka Naval Arsenal | 5 October 1943 | 25 January 1944 | 31 March 1944 | Decommissioned on 30 November 1945. Surrendered to United Kingdom, 14 August 1947. Later scrapped. |
| #2709 | No.18 | Mitsubishi, Nagasaki Shipyard | 1 November 1943 | 11 January 1944 | 8 March 1944 | Sunk by USAAF aircraft to east of Quảng Ngãi, 29 March 1945. |
| #2710 | No.20 | Mitsubishi, Nagasaki Shipyard | 1 November 1943 | 11 January 1944 | 11 March 1944 | Heavy damaged by USAAF aircraft to northwest of San Fernando, 29 December 1944. Sunk on 30 December 1944. |
| #2711 | No.22 | Mitsubishi, Nagasaki Shipyard | 1 November 1943 | 27 January 1944 | 24 March 1944 | Decommissioned on 30 November 1945. Surrendered to United States, 5 September 1947. Scrapped on 31 December 1947. |
| #2712 | No.24 | Mitsubishi, Nagasaki Shipyard | 1 November 1943 | 27 January 1944 | 28 March 1944 | Sunk by USS Archerfish at west of Iwo Jima, 28 June 1944. |
| #2713 | No.26 | Mitsubishi, Nagasaki Shipyard | 1 February 1944 | 11 April 1944 | 31 May 1944 | Decommissioned on 30 November 1945. Surrendered to United States, 6 September 1947. Scrapped on 13 October 1947. |
| #2714 | No.28 | Mitsubishi, Nagasaki Shipyard | 1 February 1944 | 11 April 1944 | 31 May 1944 | Sunk by USS Blenny at Dasol Bay, 24 December 1944. |
| #2715 | No.30 | Mitsubishi, Nagasaki Shipyard | 15 February 1944 | 10 May 1944 | 26 June 1944 | Sunk by British P-51s from the 15th Fighter Squadron at Yura, 28 July 1945. Salvaged and scrapped 1948. |
| #2716 | No.32 | Mitsubishi, Nagasaki Shipyard | 15 March 1944 | 10 May 1944 | 30 June 1944 | Decommissioned on 5 October 1945. Surrendered to United Kingdom, 16 July 1947. Later scrapped. |
| #2717 | No.34 | Tōkyō Ishikawajima Shipyard | 25 March 1944 | 6 July 1944 | 25 August 1944 | Decommissioned on 5 October 1945. Surrendered to Soviet Union, 5 July 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-32 (1947), target ship TsL-63 (1954), repair ship PM-75 (1957). Decommissioned on 23 July 1958 and scrapped. |
| #2718 | No.36 | Fujinagata Shipyards | 20 March 1944 | 16 September 1944 | 21 October 1944 | Decommissioned on 5 October 1945. Surrendered to United States, 19 July 1947. Scrapped on 3 January 1948. |
| #2719 | No.38 | Kawasaki, Kōbe Shipyard | 2 April 1944 | 15 June 1944 | 10 August 1944 | Sunk by USS Hardhead at west of Corregidor, 25 November 1944. |
| #2720 | No.40 | Fujinagata Shipyards | 20 March 1944 | 15 November 1944 | 22 December 1944 | Decommissioned on 30 November 1945. Surrendered to Republic of China 29 August 1947, and renamed Chenan (PF-72). Decommissioned 1963. |
| #2721 | No.42 | Mitsubishi, Nagasaki Shipyard | 15 April 1944 | 7 July 1944 | 25 August 1944 | Sunk by USS Puffer to northwest of Agunijima Island, 10 January 1945. |
| #2722 | No.44 | Mitsubishi, Nagasaki Shipyard | 15 April 1944 | 7 July 1944 | 31 August 1944 | Decommissioned on 5 October 1945. Surrendered to United States, 5 July 1947. Sunk as target at 34°48′N 139°42′E﻿ / ﻿34.800°N 139.700°E﻿ / 34.800; 139.700, 25 August 1947. |
| #2723 | No.46 | Kawasaki, Kōbe Shipyard | 1 May 1944 | 30 June 1944 | 29 August 1944 | Sunk by naval mine at Mokpo, 17 August 1945. |
| #2724 | No.48 | Fujinagata Shipyards | 15 May 1944 | 18 January 1945 | 13 March 1945 | Decommissioned on 30 November 1945. Surrendered to Soviet Union, 28 August 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-42 (1947), target ship TsL-42 (1948), dispatch ship Abakan (1949). Decommissioned on 2 June 1959 and scrapped. |
| #2725 | No.50 | Tōkyō Ishikawajima Shipyard | 8 July 1944 | 9 September 1944 | 13 October 1944 | Decommissioned on 20 November 1945. Scrapped on 5 May 1948. |
| #2726 | No.52 | Mitsubishi, Nagasaki Shipyard | 15 May 1944 | 7 August 1944 | 25 September 1944 | Decommissioned on 5 October 1945. Surrendered to Soviet Union, 29 July 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-36 (1947), tdispatch ship Naryn (1954). Decommissioned on 11 March 1958 and scrapped. |
| #2727 | No.54 | Mitsubishi, Nagasaki Shipyard | 15 May 1944 | 7 August 1944 | 30 September 1944 | Heavy damaged by USN aircraft at Calayan, 15 December 1944. Later scuttled. |
| #2728 | No.56 | Kawasaki, Kōbe Shipyard | 1 June 1944 | 30 July 1944 | 27 September 1944 | Sunk by USS Bowfin to south of Tateyama, 17 February 1945. |
| #2729 | No.58 | Fujinagata Shipyards | 15 April 1945 | 1945 | 8 April 1946 | Surrendered incomplete, completed post-war for repatriation duties; handed over to United States 31 July 1947. Scrapped at Sasebo on 30 November 1947. |
| #2730 | No.60 | Kawasaki, Kōbe Shipyard | 16 June 1944 | 15 September 1944 | 9 November 1944 | Decommissioned on 5 October 1945. Surrendered to United Kingdom, 14 August 1947. Later scrapped. |
| #2731 | No.62 | Hitachi Zōsen, Mukōjima Shipyard | | | | Construction stopped on 22 May 1945. Sunk at Kure, 14 January 1946. Salvaged and scrapped, May 1948. |
| #2732 | No.64 | Mitsubishi, Nagasaki Shipyard | 8 July 1944 | 5 September 1944 | 15 October 1944 | Sunk by USS Pipefish at east of Hainan Island, 3 December 1944. |
| #2733 | No.66 | Mitsubishi, Nagasaki Shipyard | 8 July 1944 | 5 September 1944 | 21 October 1944 | Sunk by USN aircraft off Shantou, 13 March 1945. |
| #2734 | No.68 | Kawasaki, Kōbe Shipyard | 3 July 1944 | 30 September 1944 | 20 November 1944 | Sunk by USN aircraft to west of Amami Ōshima, 24 March 1945. |
| #2735 | No.70 | Hitachi Zōsen, Mukōjima Shipyard | 1945 | | | Construction stopped on 1 April 1945. Later scrapped. |
| #2736 | No.72 | Tōkyō Ishikawajima Shipyard | 18 August 1944 | 23 October 1944 | 25 November 1944 | Sunk by USS Haddo at west of Taedong River, 1 July 1945. |
| #2737 | No.74 | Mitsubishi, Nagasaki Shipyard | 1 August 1944 | 2 November 1944 | 10 December 1944 | Sunk by USN aircraft at Muroran, 14 July 1945. |
| #2738 | No.76 | Mitsubishi, Nagasaki Shipyard | 1 August 1944 | 18 November 1944 | 23 December 1944 | Decommissioned on 30 November 1945. Surrendered to Soviet Union, 28 August 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-44 (1947), target ship TsL-44 (1948), patrol ship SKR-49 (1954). Refitted, rearmed and ceded to Chinese People's Liberation Army on 25 June 1955. |
| #2739 | No.78 | Kawasaki, Senshū Shipyard | | 1945 | 4 April 1946 | Surrendered to Soviet Union, 29 July 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-37 (1947), dispatch ship Murgab (1954). Decommissioned on 11 March 1958 and scrapped. |
| #2740 | No.80 | Hitachi Zōsen, Mukōjima Shipyard | 1945 | | | Construction stopped on 1 April 1945. Later scrapped. |
| #2741 | No.82 | Mitsubishi, Nagasaki Shipyard | 6 September 1944 | 18 November 1944 | 31 December 1944 | Sunk by Russian aircraft to ENE of Kimchaek, 10 August 1945. |
| #2742 | No.84 | Mitsubishi, Nagasaki Shipyard | 6 September 1944 | 18 November 1944 | 31 December 1944 | Sunk by USS Hammerhead at ENE of French Indochina, 29 March 1945. |
| #2743 to #2750 | Even numbers from No.86 to No.100 | | | | | Cancelled in August 1944. |
| #2751 | No.102 | Mitsubishi, Nagasaki Shipyard | 1 September 1944 | 4 December 1944 | 20 January 1945 | Decommissioned on 30 November 1945. Surrendered to Soviet Union, 28 August 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-46 (1947), target ship TsL-46 (1948). Decommissioned on 21 January 1960 and scrapped. |
| #2752 | No.104 | Mitsubishi, Nagasaki Shipyard | 1 September 1944 | 16 December 1944 | 31 January 1945 | Decommissioned on 30 November 1945. Surrendered to Republic of China 29 August 1947, and renamed Taian (PF-71). Decommissioned 1963. |
| #2753 | No.106 | Tōkyō Ishikawajima Shipyard | 18 September 1944 | 7 December 1944 | 14 January 1945 | Decommissioned on 5 October 1945. Surrendered to United States, 5 July 1947. Sunk as target at 34°45′N 139°44′E﻿ / ﻿34.750°N 139.733°E﻿ / 34.750; 139.733, 21 July 1947. |
| #2754 #2755 | No.108 No.110 | | - | - | - | Cancelled in Spring 1944. |
| #2756 | No.112 | Kawasaki, Senshū Shipyard | 10 May 1944 | 5 September 1944 | 24 October 1944 | Sunk by USS Barb at northeast of Cape Crillon, 18 July 1945. |
| #2757 | No.114 | | | | | Cancelled in Spring 1944. |
| #2758 | No.116 | Ishikawajima Heavy Industries | | 1945 | 28 November 1945 | Decommissioned 25 March 1946. Later scrapped. |
| #2759 | No.118 | Kawasaki, Kōbe Shipyard | 8 June 1944 | 20 November 1944 | 27 December 1945 | Decommissioned on 5 October 1945. Surrendered to Republic of China 31 July 1947. Captured by People's Liberation Army, May 1949, and renamed Changsha (216). Decommissioned in 1982. |
| #2760 | No.120 | | | | | Cancelled in Spring 1944. |
| #2761 | No.122 | Tōkyō Ishikawajima Shipyard | | | | Construction stopped in March 1945. Later scrapped. |
| #2762 | No.124 | Kawasaki, Senshū Shipyard | 29 June 1944 | 12 January 1945 | 9 February 1945 | Decommissioned on 30 November 1945. Scrapped on 1 February 1948. |
| #2763 | No.126 | Kawasaki, Senshū Shipyard | 7 November 1944 | 25 February 1945 | 26 March 1945 | Decommissioned on 5 November 1945. Surrendered to United Kingdom, 14 August 1947. Later scrapped. |
| #2764 | No.128 | | | | | Cancelled in Spring 1944. |
| #2765 | No.130 | Harima Zōsen | 22 February 1944 | 24 May 1944 | 12 August 1944 | Sunk by USAAF aircraft at east of Quảng Ngãi, 29 March 1945. |
| #2766 | No.132 | Harima Zōsen | 10 April 1944 | 25 June 1944 | 7 September 1944 | Decommissioned on 5 October 1945. Scrapped on 2 July 1948. |
| #2767 | No.134 | Harima Zōsen | 26 May 1944 | 29 July 1944 | 30 September 1944 | Sunk by USAAF aircraft to south of Xiamen, 6 April 1945. |
| #2768 | No.136 | | | | | Cancelled in Autumn 1944. |
| #2769 | No.138 | Harima Zōsen | 27 June 1944 | 1 September 1944 | 23 October 1944 | Sunk by aircraft at San Fernando, 2 January 1945. |
| #2770 | No.140 | | | | | Cancelled in Autumn 1944. |
| #2771 | No.142 | Kawasaki, Senshū Shipyard | | 1945 | 7 April 1946 | Surrendered to Soviet Union, 29 July 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-38 (1947), target ship TsL-38 (1948), dispatch ship Arkhara (1949), patrol ship SKR-48 (1954). Refitted, rearmed and ceded to Chinese People's Liberation Army on 11 February 1955. Under the name Chih-17 served until 1987. |
| #2772 | No.144 | Harima Zōsen | 1 August 1944 | 10 October 1944 | 23 November 1944 | Sunk by USS Besugo at east of Malay Peninsula, 2 February 1945. |
| #2773 #2774 | No.146 No.148 | | | | | Cancelled in Autumn 1944. |
| #2775 | No.150 | Harima Zōsen | 4 September 1944 | 15 November 1944 | 24 December 1944 | Decommissioned on 5 October 1945. Surrendered to United States, 4 July 1947. Sunk as target at 35°28′N 123°25′E﻿ / ﻿35.467°N 123.417°E﻿ / 35.467; 123.417, 18 August 1947. |
| #2776 | No.152 | | | | | Cancelled in Autumn 1944. |
| #2777 | No.154 | Harima Zōsen | 12 October 1944 | 26 December 1944 | 7 February 1945 | Decommissioned on 30 November 1945. Surrendered to United Kingdom, 4 September 1947. Scrapped on 1 March 1948. |
| #2778 | No.156 | Harima Zōsen | 17 November 1944 | 25 January 1945 | 8 March 1945 | Decommissioned on 30 November 1945. Surrendered to United Kingdom, 4 September 1947. Scrapped on 11 December 1947. |
| #2779 | No.158 | Harima Zōsen | 28 December 1944 | 25 February 1945 | 13 April 1945 | Decommissioned on 5 October 1945. Surrendered to United States, 25 July 1947. Scrapped on 31 December 1947. |
| #2780 | No.160 | Harima Zōsen | 27 January 1945 | 10 April 1945 | 16 August 1945 | Decommissioned on 5 October 1945. Surrendered to United Kingdom, 8 September 1947. Scrapped on 21 February 1948. |
| #2781 to #2792 | Even numbers from No.162 to No.184 | | | | | Cancelled in Autumn 1944. |
| #2793 | No.186 | Mitsubishi, Nagasaki Shipyard | 4 November 1944 | 30 December 1944 | 15 February 1945 | Sunk by USN aircraft at Amami Ōshima, 2 April 1945. |
| #2794 | No.188 | | | | | Cancelled in Autumn 1944. |
| #2795 | No.190 | Mitsubishi, Nagasaki Shipyard | 20 November 1944 | 16 January 1945 | 21 February 1945 | Decommissioned on 30 November 1945. Scrapped on 31 March 1948. |
| #2796 | No.192 | Mitsubishi, Nagasaki Shipyard | 5 December 1944 | 30 January 1945 | 28 February 1945 | Decommissioned on 25 October 1945. Surrendered to Republic of China 31 July 1947, and renamed Tsuan. Decommissioned 1952. |
| #2797 | No.194 | Mitsubishi, Nagasaki Shipyard | 18 December 1944 | 15 February 1945 | 15 March 1945 | Decommissioned on 5 October 1945. Surrendered to Republic of China 6 July 1947, and renamed Weihai. Captured by People's Liberation Army, 23 April 1949, and renamed Tsinan (219). Decommissioned 1982. |
| #2798 | No.196 | Mitsubishi, Nagasaki Shipyard | 31 December 1944 | 26 February 1945 | 31 March 1945 | Decommissioned on 30 November 1945. Surrendered to Soviet Union, 5 July 1947. Served in Soviet Pacific Ocean Fleet as patrol ship EK-33 (1947), dispatch ship Turgai (1954). Decommissioned on 11 March 1958 and scrapped. |
| #2799 | No.198 | Mitsubishi, Nagasaki Shipyard | 17 January 1945 | 26 February 1945 | 31 March 1945 | Decommissioned on 5 October 1945. Surrendered to Republic of China 31 July 1947. Captured by People's Liberation Army, May 1949, and renamed Sian (220). Decommissioned 1982. |
| #2800 | No.200 | Mitsubishi, Nagasaki Shipyard | 31 January 1945 | 19 March 1945 | 20 April 1945 | Decommissioned on 30 November 1945. Scrapped on 1 July 1948. |
| #2801 | No.202 | Mitsubishi, Nagasaki Shipyard | 16 February 1945 | 2 April 1945 | 7 July 1945 | Decommissioned on 30 November 1945. Scrapped on 1 January 1948. |
| #2802 | No.204 | Mitsubishi, Nagasaki Shipyard | 27 February 1945 | 14 April 1945 | 11 July 1945 | Decommissioned on 20 November 1945. Scrapped on 31 January 1948. |
| #2803 to #2843 | Even numbers from No.206 to No.286 | | | | | Cancelled in Autumn 1944. |
| 57 ships | Even numbers from No.288 onwards | - | - | - | - | Projected only, never ordered |