 Wainwright reported her first scrape with a German submarine on 11 May. She sighted an abandoned lifeboat at about 08: 00. After investigating the drifting boat for occupants and finding none, she sank the boat with gunfire. At about 08: 15, a lookout reported that a torpedo had missed the destroyer some 150 yards (140 m) astern. Wainwright then fired several rounds from her 4-inch (102 mm) guns at what was thought to be a periscope. The supposed submarine disappeared soon thereafter; and, despite a thorough investigation of the area, the destroyer could turn up no more evidence of the presence of a U-boat.
