Fog shrouded her area during the last days of the month. On 2 April, visibility was still poor, less than . At 07:10, she made radar contact with an enemy convoy-four merchantmen and three escorts. At 09:15, she commenced firing at the lead merchant ship. Forty seconds later, she fired at the next ship. She then swung around to bring her stern tubes to bear on a third merchant ship; found herself well inside the escort on the convoy's starboard quarter; continued swinging and fired three stern shots at the escort. Between 08:19 and 08:22, seven hits were heard and felt.