On 25 February 1946, "Sakawa" was sent to Yokosuka, where she was formally handed 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 her leaky hull infested with rats, and that most of the ship's systems were not functional. Together with the battleship , the ship departed Yokosuka for Eniwetok with a 165-man American crew on 18 March, with eleven of her former Japanese officers aboard to assist them. Ten days later, from Eniwetok, "Sakawa" broke down and "Nagato" attempted to tow the cruiser, but had a boiler failure and then ran out of fuel. An oil tanker, , was diverted to refuel the ships, but ran aground on a reef in bad weather and was lost. The two ex-Japanese ships were finally taken in tow on 30 March, with "Sakawa" reaching Eniwetok two days later.