Langley's aeronautical research: A modern critique and reassessment

Samuel Langley, third Secretary of the Smithsonian, was also the first U.S. government in-house researcher in aerodynamics. By 1890, he had carried put a carefully conceived, accurately engineered series of aerodynamic experiments that provided a database for the design of his steam-powered aerodromes, successfully flown in 1896. Langley's work is examined from a modern perspective. The aerodrome flights of 1896 are discussed. Particular emphasis is placed on a reassessment of Langley's aerodynamic experiments and data. The Langley law for the variation of power required as a function of velocity, which was immediately controversial in his time and remained so until the present, is finally explained for the first time, and the controversy removed. Also, Langley produced the first definitive data showing the aerodynamic superiority of high-aspect-ratio wings. Those data, if they had been properly appreciated by the Wright brothers, might have greatly improved their early glider designs. This presentation also compares and contrasts Langley's aerodynamic data with the contemporary data of Lilienthal. In general, Langley's aerodynamics, vis-a-vis the aerodynamics of Lilienthal and the Wright brothers, is brought into clearer focus.