May, E18 sailed on her final patrol; E1, E8, and two Russian submarines left the same day. Records differ on her exact fate, but it is certain neither she nor any of her crew survived. The diary of Francis Goodhart, commander of E8, states that E1 and the Russian Bars departed at 1400 hrs, E8, E18 and the Russian Gerpard left port together at 1800 hrs on 25 May; E8s patrol was uneventful, and she returned to Reval on the 31st. However, E18 failed to return; by 5 June Goodhart noted that the crews were "very worried". On the 6th, he noted that he had "Heard from Essen that their W.T. had vaguely indicated presence of a submarine off Redshoff" on Tuesday. Very slender hope..." By the next day, 8 June, he recorded that a meeting had noted she had sailed with only 15 days food; the situation was "very hopeless now, I fear. No news whatsoever" By the 9 June E8's officers began collecting the belongings of E18's Halahan, Landale and Colson from their cabins. Michael Wilson, a historian, records that E8 and E18 sailed on the 25th and parted the next day. On the 26th, at 4:42 PM, E18 torpedoed the German destroyer V100, blowing off her bow. Had it not been for the calm seas, it is likely she would have sunk from the damage; as it was, she was towed back to port with several of her crew killed, requiring major repairs. Two days later, on the 28th, E18 was sighted by a German aircraft off Memel (now Klaipėda, Lithuania), E18 was last sighted on the 1 June 1916 at 1500 hrs sailing north by the German U-boat UB-30 northwest of Steinort. Wilson further states that it is believed she was lost "most likely by striking a mine" on her return to Reval west of Osel. The logs of the German destroyers with V100 also support the same dates as Goodhart's diary and Wilson's observations. Various sources record her simply as having been sunk on 24 May by a German decoy ship, though this clashes with the known attack on V100 on the 26th and the observations reported by Wilson and Goodhart in subsequent days. It is quite possible that this is a garbling of an encounter between one of the Russian submarines and a decoy vessel around the same time. The German decoy ship Kronprinz