Helicopter pilots in Vietnam kidded one another about being nothing but glorified bus drivers. But these "rotor heads" saved thousands of American lives while performing what the Army classified as the most dangerous job it had to offer. One in eighteen did not return home. Tom A. Johnson flew the UH-1 "Iroquois" -- better known as the "Huey" -- in the 229th Assault Helicopter Battalion of the First Air Cavalry Division. From June 1967 through...