This subseries consists of materials of a scientific or technical nature relating to aviation. These include a 1904 article by Albert Francis Zahm on atmospheric friction on even surfaces; two published papers, 1925 and 1934, by Alfred Hubert Roy Fedden on aero-cooled engines; and a 1934 U.S. Army Air Corps handbook on aerodynamic formulae. Materials that appear to have been prepared for use in an educational setting include a typescript course on stability and control of flight, circa 1940, by H. G. Mazurkiewicz; Weems System of Navigation course on celestial navigation, 1941; and a binder marked "Haskins", containing printed, typed, and handwritten documents and reports on supercharging engines, and other engineering subjects, dated 1930-1945, and originating at Purdue University. The subseries also includes Air Service Tactical School, Langley, VA, combat orders for 1925-1926, and a 1943 report to the Civil Aeronautics Board on air pick-up service.