World War II
The unit was established in late 1943 at El Paso Municipal Airport, Texas, being formed as a B-29 Superfortress Very Heavy bombardment Group. The unit was formed with four bomb squadrons (869th, 870th, 871st and 872d), all being newly constituted.
It moved to Pratt Army Air Field, Kansas in December 1943 to begin training. Due to a shortage of B-29s, the group was equipped with former II Bomber Command B-17 Flying Fortresses already at Pratt which were previously used for training heavy bomber replacement personnel. In the spring of 1944, it finally received newly manufactured B-29 Superfortresses. In May shortages in aircraft and equipment led to the 872d Bomb Squadron being inactivated, with its personnel being consolidated into other group squadrons.
As a three squadron group, the 497th was deployed to Pacific Theater of Operations (PTO) in September 1944, being assigned to the XXI Bomber Command 73d Bombardment Wing in the Northern Mariana Islands; being stationed at Isely Field, Saipan. Upon arrival the group's personnel were engaged in Quonset hut construction. By mid-October most personnel were able to move into the huts from the initial tents which they were assigned on arrival. The group began operations in October 1944 with attacks against Iwo Jima and the Truk Islands. Took part in the first attack (24 November 1944) on Japan by AAF planes based in the Marianas. Flew many missions against strategic objectives in Japan; on numerous raids, made its attacks in daylight and from high altitude.
Received a Distinguished Unit Citation for a mission on 27 January 1945. Although weather conditions prevented the group from bombing its primary objective, the unescorted B-29’s withstood severe enemy attacks to strike an alternate target, the industrial area of Hamamatsu. Awarded a second DUC for attacking strategic centers in Japan during Jul and August 1945. Assisted the assault on Okinawa in April 1945 by bombing enemy airfields to cut down air attacks against the invasion force. Beginning on 19 March and continuing until the end of the war the group made incendiary raids against Japan, flying at night and at low altitude to bomb area targets. The group released propaganda leaflets over the Japanese home islands, July–August, continuing strategic bombing raids and incendiary attacks until the Japanese Capitulation in August 1945.
After V-J Day, the 497th dropped supplies to Allied prisoners, participated in show-of-force missions, and flew over Japan to evaluate bombardment damage. In November 1945 the unit returned to the United States; initially being assigned to Continental Air Forces's (CAF) Fourth Air Force at March Field, California. At March Field, the 513th Bombardment Squadron joined the group; it previously being a Fifteenth Air Force B-24 Liberator squadron based in Italy, having been returned to the United States in May and was undergoing B-29 Very Heavy Bomber upgrade training in Nebraska when its former assigned group, the 376th Bombardment Group, was inactivated.
In January 1945, the 497th was reassigned to the CAF Third Air Force at MacDill Field, Florida. It later was transferred to the new Strategic Air Command on 21 March 1946, being one of SAC's initial bombardment groups. Demobilization, however, was in full swing and the group turned in its aircraft and was inactivated on 31 March.
United States 
United States Air Force 
