Since icebergs travel fairly slowly, over-the-horizon radar can spot them 100 miles off, and ocean tugs try to push or tow them out of the way.

The ocean going tug remained under the operational control of the commanding officer, U.S. Naval Station.

She was reclassified an old ocean tug and was redesignated ATO-21 on 15 May 1944.

On his third patrol, in December 1942, Brandi sank the ocean tug St Issey, and two more merchant ships.

On 4 June, the ocean tug got underway for Midway Island.

The ocean tug returned Pearl Harbor 7 September 1945 and from there set course for San Francisco.

During the fall of 1945, the ocean tug saw service with the occupation forces in the Far East.

On 19 May, the auxiliary ocean tug departed New Orleans towing YF-756.

With the end of hostilities, the ocean tug operated for a short time out of Chinese ports.

Meanwhile, on 15 May 1944, she had been reclassified as an old ocean tug and redesignated ATO-143.