The AGO S.I was a German prototype ground-attack aircraft built in October 1918 but possibly never flown before the end of World War I. It was a single-seat biplane armed with a downwards-firing 20 mm cannon.

General characteristics

• Crew: one, pilot
• Powerplant: 1 × Basse und Selve BuS.III , 113 kW (150 hp)

Performance Armament

• 2 × machine guns
• 1 × 20 mm Becker cannon

• Herris, Jack (2012). German Armored Warplanes of WWI: A Centennial Perspective of Great War Airplanes. Great War Aviation Centennial Series. Vol. 4. Charleston, South Carolina: Aeronaut Books. ISBN 978-1-935881-11-7.
• Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p. 40.