On her second patrol from Beirut, "Sickle"s electric motors were damaged during an attack by two destroyers, so she sailed to Gibraltar for repairs. Several months later, the boat returned to service and conducted two patrols in the Aegean, sinking another three caïques, a sailing vessel, and a merchant ship. On 31 May 1944, "Sickle" departed Malta for a patrol in the Aegean and did not return. It is considered probable that she hit mines on her way back to Malta around 16–18 June 1944.