The swept-wing F-111 is flown by the U.S. Air Force's 474th Tactical Fighter Wing. The 474th was the first operation unit in the Air Force to be equipped with the F-111. This photograph was probably taken over Nellis Air Force Base (Nevada).
Black and white image showing the beginning of a 5000-hole dynamite blast in Black Canyon at the site of Hoover Dam construction. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image showing a river-level view of canyon blasting in Black Canyon at the site of Hoover Dam construction. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image of two men standing in front of penstock tunnel piping at the site of Hoover Dam construction. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image of Hoover Dam construction, including work on the dam forms and intake towers. Note: Boulder Dam was officially renamed Hoover Dam in 1947.