up, and advised them to refrain from talking, singing or smoking in order to preserve precious oxygen. Despite numerous attempts by engineers, divers, and US and Turkish naval vessels, the rescue efforts were unsuccessful due to the severe currents and the depth of the Dumlupınar, and the morale of the trapped crew began to decline. By afternoon, the voices of the 22 sailors were quieting, and were being replaced by prayers. Finally, the rescue workers told the sailors, "Gentlemen, now you can talk, you can sing, you can even smoke". Lt. Özben responded with a final "For our country", and at approximately 15:00 (3pm) on 4 April, the cable that was holding the communications buoy broke, disconnecting the last means of communication between the surface and the doomed submarine. Despite the lack of communication, operations continued in order to rescue the trapped men, attracting widespread attention from the Turkish public. On 7 April 1953, three days after the accident, it was declared that the rising carbon dioxide levels inside the submarine would have killed any surviving crew, and the rescue operation was abandoned. The following day, at 15:00 (3pm), a memorial ceremony was held on the ship Başaran. The incident, has since inspired numerous songs and tributes in honor of the fallen sailors, and is commemorated every year in Turkey on 4 April. References External links History of Turkish Submarines (1948–1972) Balao-class submarines Ships built in Groton, Connecticut 1944 ships World War II submarines of the United States Cold War submarines of the United States Ships transferred from the United States Navy to the Turkish Navy Balao-class submarines of the Turkish Navy Ships sunk in collisions Shipwrecks in the Dardanelles Maritime incidents in 1953