Acquired by the U.S. Navy on 2 April 1953, she was designated YAG-39 the following month. She was then fitted out with numerous scientific instruments, including nuclear detection and measurement devices, which enabled her to conduct contamination and fallout measurement tests after nuclear explosions. Manned by an experimental crew in a specially protected control cubicle, she also was fitted with electronic remote control gear that enabled her to serve as a robot ship.