Heavy bomber replacement training The
331st Bombardment Group was first activated in July 1942 at
Salt Lake City Army Air Base, Utah with the
461st,
462d,
463d and
464th Bombardment Squadrons assigned. In September it moved to
Casper Army Air Field, where it conducted
Boeing B-17 Flying Fortress replacement training until 1943, when it converted to the
Consolidated B-24 Liberator. Replacement training units were oversized units which trained
aircrews prior to their deployment to combat theaters. However, the
Army Air Forces found that standard military units, based on relatively inflexible tables of organization, were not proving to be well adapted to the training mission. Accordingly, it adopted a more functional system in which each base was organized into a separate numbered unit, while the groups and squadrons acting as replacement training units were disbanded or inactivated. This resulted in the 331st, along with other units at Casper, being inactivated in the spring of 1944 and being replaced by the 211th AAF Base Unit (Combat Crew Training Station, Heavy), which assumed the 331st Group's mission, personnel, and equipment.
Very heavy bomber operations It was redesignated the
331st Bombardment Group, Very Heavy and activated on 12 July 1944 at
Dalhart Army Air Field, Texas and assigned to Second Air Force. It trained for combat with B-29B's initially at Dalhart, then at
McCook Army Air Field, Nebraska. The 331st was assigned the B-29B model. This model was built by
Bell Aircraft's Atlanta plant. The B-29B was a limited production aircraft, built solely by Bell-Atlanta. It had all but the tail defensive armament removed, since experience had shown that by 1944 the only significant Japanese fighter attacks were coming from the rear. The tail gun was aimed and fired automatically by the new AN/APG-15B radar fire control system that detected the approaching enemy plane and made all the necessary calculations. The elimination of the turrets and the associated General Electric computerized gun system increased the top speed of the Superfortress to 364 mph at 25,000 feet and made the B-29B suitable for fast, unescorted hit-and-run bombing raids and photographic missions. It moved to Northwest Field, Guam, April–June 1945, and was assigned to the
315th Bombardment Wing of
Twentieth Air Force. It bombed Japanese-held
Truk late in June 1945. It flew its first mission against the Japanese home islands on 9 July 1945 and afterward operated principally against the enemy's petroleum industry on Honshū. Despite the hazards of bad weather, fighter attacks, and heavy flak, the 331st bombed the coal liquefaction plant at
Ube, the Mitsubishi-Hayama petroleum complex at
Kawasaki, and the oil refinery and storage facilities at
Shimotsu, in July and August 1945, and received a
Distinguished Unit Citation for the missions. After the war the group dropped food and supplies to Allied prisoners of war in Japan. It was inactivated on Guam on 15 April 1946.
Hurricane Ike (2008) The unit was reactivated at
Randolph Air Force Base, Texas, in 2008 as the
331st Air Expeditionary Group, a special unit formed to support
Hurricane Ike relief efforts. Units and personnel assigned to the 331st came from both the active and reserve components of the Air Force and Navy. ==Lineage==