After arriving in Boston, the ship was extensively examined by the US Navy. Her very large GHG passive sonar array was removed and installed on the submarine for testing. American interest in magnetic amplifier technology increased again after findings in investigations of the fire control system of "Prinz Eugen". The guns from turret Anton were removed while in Philadelphia in February. On 1 May the German crewmen left the ship and returned to Germany. Thereafter, the American crew had significant difficulties in keeping the ship's propulsion system operational—eleven of her twelve boilers failed after the Germans departed. The ship was then allocated to the fleet of target ships for Operation Crossroads in Bikini Atoll. Operation Crossroads was a major test of the effects of nuclear weapons on warships of various types. The trouble with "Prinz Eugen"s propulsion system may have influenced the decision to dispose of her in the nuclear tests.