Alexander P. de Seversky and the Quest for Air Power

5. The Russian Inventor

64 5 The Russian Inventor On March 22, 1921, Alexander P. de Seversky arrived at McCook Field, Dayton, Ohio, home to the U.S. Army Air Service Engineering Division, carrying with him letters of introduction. They revealed to Maj. Thurman H. Bane, division chief, a strong desire on the part of General Mitchell to have de Seversky fashion for the air service, first, an effective bombsight, but also the technology for transferring fuel from one airplane to another during flight. The Russian joined a group of civilians employed by the division that conducted research and development for all aspects of military aircraft, including design, construction materials, airframes, engines, propellers, parachutes, cameras, radio navigation, fuel systems, superchargers, and instruments of all types. After the U.S. Congress passed legislation reorganizing the air service as the U.S. Army Air Corps in 1926, the unit became the Materiel Division and moved to nearby Wright Field, later renamed the Wright-Patterson Air Force Base (AFB).1 The Engineering Division Meanwhile, Maj. L. W. McIntosh, assistant chief of the Engineering Division , took de Seversky on a tour of McCook Field. Besides aircraft sheds, the field sported laboratories to test propellers, airspeed devices, and wings or airframes; it also possessed a dynamometer laboratory plus several workshops, including one for designing and developing mechanisms such as bombsights. As part of the tour, the Russian met and conversed with three figures with whom he would collaborate occasionally over the next eighteen months: Maj. Eddie L. Hoffman, in charge of the Equipment Branch; Capt. Harold Harris, who headed the Flight Test Branch; 65 The Russian Inventor and Henry B. Inglis, former captain turned civilian who now focused his mechanical engineering skills on assisting the Russian with the bombsight. And de Seversky needed the help of an engineer as well as an instrument manufacturer because his bombsight was far more complex than those employed during the Great War.2 Once pilots or bombardiers in World War I discovered guesswork or intuition failed to let them know when to release a bomb, they turned to physics. The prime ingredients requiring analysis centered on the altitude and speed of the bomber, the wind direction, and the measure of both inertia and gravity on a free-falling bomb dropped from a moving airplane. A device that attempted to account for most of these factors was adopted by the U.S.A.A.S. from the work of Lt. Cdr. Harry E. Wimperis of Great Britain’s Royal Naval Air Service. The early Wimperis employed two rifletype sights adjusted for speed, altitude, and the ballistics of the bomb. To avoid the impact of wind drift on falling ordnance, pilots flew directly into or away from the wind and released bombs when the front and rear sights lined up on the target. The Wimperis had a chance to work but only at a low altitude and in a perfect scenario in which the plane’s heading remained absolutely straight and level.3 Unfortunately, reality intruded on this scenario. At 10,000 feet, the Wimperis had “circular error probable” over a target of more than 600 feet. But why? The answer resides in part in the fact that an airplane in flight is a floating object in a gaseous fluid; it simply oscillates as a matter of course. A virtually unnoticeable change in pitch up or down of only one degree would cause a bomb to miss its target completely. De Seversky had a solution to this problem. As an officer trained in the Imperial Russian Navy, he was familiar with another vehicle that oscillated in a different kind of fluid: the warship in water. Similar to a serious bombardier in an airplane, a battleship’s gunner had to consider the pitch of his craft. Major war vessels constructed or reequipped shortly before or after 1914 often contained gyroscopes to provide the stability necessary so gunners could accurately fire a salvo against enemy ships.4 During the recent global conflict, de Seversky began experimenting with the notion of merging a ship’s gyroscope with an airplane’s bombsight. He also started to develop a calculator, a primitive computer that would quickly synchronize the numbers of an airplane’s altitude and speed with the vector of a falling bomb to know the precise moment when to release 66 The Russian Inventor ordnance that actually had a chance to hit the target. De Seversky, good...