At 20.59 hours on 15 May, the now zig-zagging Kupa was torpedoed by the same U-boat, which had observed how the vessel stopped and assumed correctly that they picked up the survivors from Siljestad. All Norwegian survivors abandoned ship in their lifeboats and the boat of the master lost contact with the others that night, but spotted the illuminated Italian motor tanker Alcoa, which was en route with a British control crew to Las Palmas. Three young British sailors were transferred to the tanker, while the remaining men continued in the lifeboat to Barbados, after having been given plenty of food and water. They reached Bridgeport on May 20. The other Norwegian lifeboat and those from the Yugoslavian ship made landfall after ten days in Venezuela and Barbados.