Pierce Butler, Culver v. United States — Opinion of the Court
“ It was there stated that he considered that any officer holding a flying rating was on duty which required his participation in regular and frequent flights, no matter what the nature of that duty might be. December 31, 1921, after the controversy culminating in this suit arose, the President issued a regulation (paragraph 1269 1/2, Army Regulations) requiring all officers of the Air Service who are rated as pilots of airplanes or airships and on a duty status to participate regularly in aerial flights as pilots whenever flying facilities are available. ”
