sentences:  After returning to the United States at the end of May 1945, the unit was assigned to Second Air Force, transitioned to B-29 Superfortresses, and was redesignated a Very Heavy bomb group.In the postwar era, the 449th Bombardment Group was one of the original ten bombardment groups assigned to Strategic Air Command (SAC).The unit was inactivated on 4 August 1946 at Grand Island Army Air Field, Nebraska and its mission, aircraft, and personnel were transferred to the 28th Bombardment Group which was simultaneously activated.