Name Sakawa Laid down 21 November 1942 Struck 5 October 1945 Launched 9 April 1944 Builder Sasebo Naval Arsenal | Ordered 1939 Fiscal Year Commissioned 30 November 1944 Construction started 21 November 1942 Length 162 m | |
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Fate Sunk 2 July 1946 by atomic bomb test at Bikini Atoll | ||
Sakawa (酒匂) was an Agano-class cruiser which served with the Imperial Japanese Navy (IJN) during World War II. She was named after a river in Kanagawa prefecture, Japan. She may be best known for her use as an atomic bomb target at Bikini Atoll.
Contents
Background
Sakawa was the last of four vessels completed in the Agano class of light cruisers, which were intended to replace increasingly obsolete light cruisers in the Imperial Japanese Navy. Funding was authorized in the 4th Naval Armaments Supplement Programme of 1939, although construction was delayed due to lack of capacity in Japanese shipyards. Like other vessels of her class, Sakawa was intended for use as the flagship of a destroyer flotilla.
Design
The design for the Agano class was based on technologies developed by the experimental cruiser Yūbari, resulting in a graceful and uncluttered deck line and single smokestack.
Sakawa was armed with six 152 mm Type 41 guns in three gun turrets. Secondary armament included four 8cm/60 Type 98 naval guns designed specifically for the class, in two twin turrets amidships. Anti-aircraft weapons included two triple 25 mm AA guns in front of the bridge, and two twin 13 mm mounts near the mast. Sakawa also had two quadruple torpedo launchers for Type 93 torpedoes located below the flight deck, with eight reserve torpedoes. The torpedo tubes were mounted on the centerline, as was more common with destroyers, and had a rapid reload system with eight spare torpedoes. Being mounted on the centerline allowed the twin launchers to fire to either port or starboard, meaning that a full eight-torpedo broadside could be fired, whereas a ship with separate port and starboard launchers can only fire half of its torpedoes at a time. Two depth charge rails and 18 depth charges were also installed aft. Sakawa was also equipped with two Aichi E13A aircraft and had a flight deck with a 26-foot catapult.
The engines were a quadruple-shaft geared turbine arrangement with six boilers in five boiler rooms, developing 100,000 shp (75,000 kW) for a maximum speed of 35 knots (65 km/h).
Imperial Japanese Navy
Built at Sasebo Naval Arsenal, Sakawa was laid down on 21 November 1942, launched on 9 April 1944 and completed on 30 November 1944. On commissioning, she was assigned directly to the Combined Fleet at Yokosuka Naval District. On 15 January 1945 Sakawa became flagship of DesRon 11, training with new destroyers in the Inland Sea and participating in a series of tests of a new anti-radar submarine coating.
On 1 April 1945, Sakawa was assigned to "Operation Ten-Go", the suicide mission against the American invasion forces at Okinawa. Sakawa and her squadron of destroyers were originally scheduled to accompany the battleship Yamato with her sister ship Yahagi, but there was no fuel available for Sakawa to participate in the mission. After the loss of Yamato, Sakawa was ordered to relocate to the Maizuru Naval District, arriving on 19 July. At Maizuru, she was attacked by aircraft from the aircraft carrier USS Yorktown on 25 July, but was not damaged.
At the time of the surrender of Japan on 2 September 1945, Sakawa was docked at Maizuru, having never once been in combat. She was demilitarized, with her guns disabled, and her torpedoes, ammunition and other armaments removed. On 5 October 1945, Sakawa was officially removed from the navy list.
Post-war operations
After the conclusion of World War II, Sakawa was used to evacuate 1,339 Imperial Japanese Army troops stranded on four small islands (Sonsorol, Fanna, Merir and Hatohobei) in the southern Palau group in October 1945. She continued to work for the Repatriation Service as a transport until the end of February 1946, returning Japanese troops from New Guinea, Korea and from other locations.
On 25 February 1946, Sakawa was sent to Yokosuka, where she was formally turned over to the United States Navy as a prize of war, for use (along with other surviving ships of the former Imperial Japanese Navy) in the upcoming Bikini atomic experiments. The salvage crew found the leaky hull infested with rats, and that most of the ship's systems were not functional. Sakawa departed Yokosuka for Eniwetok with an American crew of 165 men and officers on 18 March 1946, accompanied by the battleship Nagato, also under an American crew. The ship also had eleven of her former Japanese officers aboard to assist the American crew. Ten days later, 300 nautical miles (560 km) from Eniwetok, Nagato broke down with a boiler failure, and started to take on water, listing heavily to starboard. Sakawa attempted to tow, but then ran out of fuel. An oil tanker, Nickajack Trail was diverted to refuel the ships, but ran aground on a reef in bad weather and was lost. Sakawa and Nagato, were both taken under tow, with Sakawa finally reaching Eniwetok on 1 April 1946.
While at Eniwetok, five of the ship's American sailors were angry over the dismal working conditions aboard Sakawa. In a ship normally staffed by over 730 men, the U.S. Navy used a crew of 165 doing the work of 325. The five sailors sabotaged the ship by removing the pressure line to the over-speed trip valves in the fuel system and pouring sand into the oil and water pumps. They smashed gauges, tachometers, and cut high pressure steam lines in an attempt to get relieved of duty aboard the filthy warship. Rather than being relieved of duty, the five sailors were brought up on charges. In May, after emergency repairs, Sakawa reached Bikini Atoll.
During Operation Crossroads on 1 July 1946, Sakawa and Nagato were the primary target ships in the atomic bomb air burst detonation test "Able", together with American battleships Arkansas, New York, Nevada, and Pennsylvania. Sakawa was moored off the port side of Nevada, where the bomb was to be dropped and the ship was filled with cages containing various animals to be tested for radiation effects. The detonation of the Able bomb occurred 490 yards (450 m) above and slightly to starboard of Sakawa's stern. The blast caused Sakawa to burn fiercely for twenty-four hours; the force crushed her superstructure, damaged her hull and breached her stern. After the test, a tug boat, USS Achomawi, tried to tow Sakawa toward a beach to prevent the latter ship from sinking, but failed. Sakawa started sinking almost as soon as towing began, and, with a tow cable connecting the two ships, Achomawi started to be dragged down, too. After a number of attempts, sailors cut the tow cable with an acetylene torch. Sakawa sank on 2 July 1946 in about 200 feet (60 m) of water, with a portion of the tow cable still attached.
The second weapons test, Baker, was an underwater shot about 500 feet (150 m) away from the sunken Sakawa.