01/31/2011. In 1915 the Eidgenössischen Konstruktionswerkstätte (K+W) at Thun, Switzerland, formed an aircraft construction department. As chief constructor was appointed August Häfeli, who before WW I had worked for Farman in France, and Aerowerke Gustav Otto (AGO) in Germany. Influenced by the AGO C.I, he designed the DH-1 reconnaissance aircraft, powered by a 120 hp Argus As II six-cylinder liquid-cooled in-line engine, license-built by the Buhler Brothers Limited of Uzwil, Switzerland.
Six aircraft were produced, c/n H.1 to H.6, and the first two were delivered to the Swiss AAS on April 14, 1916, the remaining four were delivered July 7, 1916. They received the Swiss AAS designation M.I and the serials 241 to 246, of which only the last two digits were painted on the tail. The aircraft performance was unsatisfying, in 1917 three were lost, 242 on April 12, 244 on July 13, and 245 on August 7. The other three were withdrawn from use on December 20, 1919.