Operation Transom was a major bombing raid on Japanese targets at Surabaya, Java by American and British planes on 17 May 1944 during World War II. Transom was the second of two raids—Operation Cockpit (against Sumatra) being the first—that marked the first major offensive raids by the British Fleet Air Arm in the Far East. The Royal Navy was building its naval strength in the Indian Ocean, in preparation for joining the war in the Pacific (see British Pacific Fleet). Transom therefore also served to provide experience in naval air raids and replenishment at sea. Planes from the aircraft carrier USS Saratoga also took part in the raids on Sumatra and Java, after a joint training exercise with the British ships.