 Trapp was transferred to , formerly the French submarine "Curie", which had been sunk and salvaged by the Austrian Navy.Trapp conducted ten more war patrols, until, in May 1918, he was promoted to "Korvettenkapitän" (equal to Lieutenant commander) and given command of the submarine base at Cattaro in the Gulf of Kotor.At the end of the fighting in 1918, Trapp's wartime record stood at nineteen war patrols; eleven cargo vessels totalling sunk, plus "Léon Gambetta" and "Nereide" sunk, and one cargo vessel captured.