 Five days later her group sailed to patrol across the Atlantic, putting into Casablanca to replenish 20 to 24 July.On 2 August, during a special hunt for submarines known to be transmitting weather information from stations in the central Atlantic, "Fiske" and were detached from the task group to investigate a visual contact both had made.The contact (north of the Azores), surfaced , quickly dived, but the two escorts picked it up on sonar, and began their attack approach.