Japanese cruiser Sakawa

The Sakawa (酒匂 軽巡洋艦) was an Agano class light cruiser which served with the Imperial Japanese Navy during World War II. It 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.

Background
Sakawa was the fourth and final of the four vessels completed in the Agano-class of light cruisers, and like other vessels of her class, she was intended for use as the flagship of a destroyer flotilla.

Imperial Japanese Navy
Sakawa was completed on 30 November 1944 at Sasebo Navy Yard and was assigned to the Combined Fleet at Yokosuka. 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 the Second Fleet for "Operation Ten-Go", the suicide mission against the American invasion forces at Okinawa. Sakawa was originally scheduled to accompany Yamato with her sister ship Yahagi, but there was no fuel available for Sakawa and her destroyer squadron. After the loss of Yamato, Sakawa was reassigned back to the Combined Fleet.

At the time of the surrender of Japan on 2 September 1945, Sakawa was at Maizuru, having never once been in combat.

On 5 October 1945, well after the war ended, Sakawa was officially removed from the Navy List.

United States Navy
Sakawa was taken as a prize of war by the United States after the conclusion of World War II, and was used to evacuate 1,339 Imperial Japanese Army troops stranded on four small islands in the southern Palau group in October 1945. It continued to work for the Repatriation Service as a transport until the end of February 1946.

On 25 February 1946, Sakawa was turned over to the US Navy, which wanted to use it (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 Nagato, also under an American crew. Ten days later, 300 nmi from Eniwetok, Nagato broke down. It blew a boiler and started to take on water, listing heavily to the 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, under tow, finally reached Eniwetok on 1 April 1946.

While at Eniwetok, five of its American sailors were angry over the dismal working conditions aboard Sakawa. In a ship normally staffed by 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 USS Arkansas, USS New York, USS Nevada, and USS Pennsylvania. Sakawa was moored off the port side of Nevada, where the bomb was to be dropped. The detonation of the Able bomb occurred 490 yd 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, the 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, the Achomawi started to be dragged down, too. After a number of attempts, sailors cut the tow cable with an acetylene torch. Sakawa sank 2 July 1946, with a portion of the tow cable still attached.

The second weapons test, Baker, was an underwater shot about 500 ft away from the sunken Sakawa.