Aircraft Recognition Slides Kahn

Recognition slides were one of the methods used in the 1940s and 1950s to train service personnel in the identification of aircraft types, as well as ship types. This collection consists of 102 glass-mounted black and white 35 mm recognition training slides with related documents issued by the Office of Naval Research Special Devices Center in Port Washington, New York.

In a combat situation, the ability to identify an aircraft quickly and accurately as friend or foe is of paramount importance. In World War I, national insignia were used for the first time to identify military aircraft used by the combatants. These insignia could be hard to spot when an aircraft in flight was seen silhouetted against a bright sky, so visual aircraft recognition training materials began to emphasize the shape of an aircraft as seen from different angles. The WEFT system, based on study of the shapes and locations of an aircraft's Wings, Engines, Fuselage, and Tail, was developed by the British just prior to and during World War II and made extensive use of three-view (bottom, front, side) silhouettes of aircraft. The WEFT system of recognition training was adopted by the US Navy and the US Army Air Corps in 1941. In 1942, a different approach to training was developed by Samuel Renshaw of Ohio State University; Renshaw's concept presented students with a brief "flash" view of an aircraft on a screen, forcing them to concentrate on the overall shape of the aircraft (whole image) rather than studying individual components (image analysis). Still picture film slides could be used both for initial identification training based on the WEFT system as well as for Renshaw-style "flash" viewing to improve recognition speed. Film slides created specifically for recognition training were typically produced with a printed cardboard frame identifying the subject of the slide sandwiched between thin glass sheets designed to both protect the film image from repeated handling and from the intense heat produced by the incandescent light sources used in slide projectors. The Office of Naval Research Special Devices Center in Port Washington, New York, produced several slide-based recognition training devices for the US military during the Cold War period following World War II.