B-18 Bolos; B-17B Flying Fortresses; A-20 Havocs, and A-17A Nomads were assigned to various groups under its control. It was replaced by the 13th Bombardment Wing in an administrative reorganization of the Panama Canal Air Force on 25 October 1941. World War II Reactivated as IX Bomber Command, the unit was assigned to Ninth Air Force in Egypt on 17 November 1942. Its component groups were: 12th Bombardment Group: c. 17 November 1942 – c. 1 November 1943, B-25 Mitchell 98th Bombardment Group: c. 17 November 1942 – c. 13 September 1943, Consolidated B-24 Liberator 321st Bombardment Group: 22 July – c. 28 September 1943, B-25 Mitchell 376th Bombardment Group: 17 November 1942 – 13 September 1943, B-17D Flying Fortress; B-24 Liberator. Formed from HALPRO components along with personnel and equipment sent from Tenth Air Force. The B-17s which were assigned were determined to be non-operational and never used in combat. IX Bomber Command was quickly put together in late 1942 to aid the British Eighth Army's drive west from Egypt into Libya against General Rommel's Afrika Corps during the Western Desert Campaign. It consisted of units and aircraft put together for an attack on Japan which was canceled after the Burma Road was captured by Japanese forces, making its planned base in China unable to support the attack (HALPRO Mission); by Pearl Harbor Attack and Philippines survivor early model B-17 Flying Fortresses that had been sent from Australia, and by some early B-24 Liberator and B-25 Mitchells which were sent across the South Atlantic Transport route from Morrison Field, Florida, via Brazil and across Central Africa via Sudan. The United States Army Air Forces (USAAF) began planning for a buildup of American air power in the Middle East in January 1942 in response to a request from the British Chief of the Air Staff. The initial unit to arrive was given the codename "Halverson Project" (HALPRO). It was under the command of Colonel Harry A. Halverson (formerly Brig Gen Billy Mitchell's Executive Officer) and consisted of twenty-three B-24D Liberator heavy bombers with hand-picked crews. It had initially been assigned to the China Burma India Theatre to attack Japan from airfields in China, but after the fall of Rangoon, the Burma Road was cut, so the detachment could not be logistically supported in China. HALPRO's first mission was flown on 12 June 1942 against the Romanian oil facilities at Ploieşti.