 On 24 October, the 48-ship convoy ran into a patrol line of German U-boats which closed to attack.Starting on the 26th, and continuing over the next two nights, seven U-boats attacked the convoy.Although the convoy escorts — including the Coast Guard cutter "Campbell" and three British Commonwealth corvettes — drove off most of the attackers, three merchant ships were sunk and another two damaged by U-boats that broke through the defensive screen.