During Operation Crossroads, the 1946 atomic bomb tests at Bikini Atoll, Power was assigned as assistant deputy task force commander for air on Admiral William H. P. Blandy's staff. Then came assignments as deputy assistant chief of air staff for operations in Washington and a period of air attaché duty in London, prior to his transfer to the Strategic Air Command as vice commander in 1948. During the next six years, Power assisted General Curtis E. LeMay, then commander in chief of the Strategic Air Command, in building up SAC. He was then appointed commander of the Air Research and Development Command in 1954, a position he held for three years.