Post Office Department
President Harry S. Truman (seated, center) signs the 5-cent Air Mail Bill in the Oval Office. Postmaster General Robert E. Hannegan is seated at right. Also pictured (l-r): Congressman George D. O'Brien; John Hart of United Airlines; Senator Dennis Chavez; Senator Carl Hayden; Congressman Charles E. McKenzie; Congressman John C. Butler; Frank J. Delaney of the Post Office Department; C.E. Fleming of Transcontinental and Western Air; Emery F. Johnson of the Air Transport Association; and Charles M. Knoble of Pennsylvania-Central Airlines.