the Adlershof trials. Three were built. Operators Belgian Air Force - operated 1 ex-Luftstreitkräfte D.IV from 1919 to 1921 Luftstreitkräfte Kaiserliche Marine Lithuanian Air Force - received 1 D.IV (No. 6177); however, it never flew in Lithuanian service. Swiss Air Force - operated 1 ex-Luftstreitkräfte D.III from 1918 to 1922. Specifications (D.IV) References Notes Bibliography Gray, Peter, and Thetford, Owen. German Aircraft of the First World War. London:Putnam, 1962. Munson, Kenneth. Aircraft of World War I. London: Ian Allan, 1967. . External links Contemporary technical description with photographs and drawings, translated from the German aviation journal Flugsport. 1910s German fighter aircraft D.IV Single-engined tractor aircraft Biplanes Aircraft first flown in 1918 Rotary-engined aircraft ja:ジーメンス・シュッケルト D.III