interrupter gear was never carried out. Instead, Dybovsky was posted to England to inspect aircraft being constructed by the Royal Flying Corps. While in Britain he worked on a true synchronization gear with the British inventor Scarff; this became the "Scarff-Dibovski" system used by the British. Thus it was that by April 1917, Russian had only a couple of dozen fighter aircraft with synchronized guns. In the interim, praporshchik Victor Kulebakin was installing cam deflectors on another Morane-Saulnier's crankshaft. Testing in July 1917 showed that the deflectors did indeed pop out from under the aircraft's cowling to deflect any bullets that threatened the propeller. Although the modification was simple enough it could be fabricated in a unit's workshops, it was not widely used. Aircraft Fighters Morane-Saulnier H Morane-Saulnier L Morane-Saulnier N Morane-Saulnier I Morane-Saulnier V Sikorsky S-16 Sikorsky S-20 Nieuport 10 Nieuport 11 Nieuport 12 Nieuport 16 Nieuport 17 Nieuport 21 Nieuport 23 Nieuport 24 Nieuport 24bis Nieuport 27 SPAD S.A-2 & -4 SPAD S.VII Sopwith Triplane Vickers FB.19 Reconnaissance Anatra D Anatra DS Curtiss F Deperdussin TT FBA Type C Grigorovich M-5 Grigorovich M-9 Grigorovich M-11 Grigorovich M-15 Farman HF.20 Morane-Saulnier G Maurice Farman MF.11 Lebed VII Lebed XI Lebed XII Morane-Saulnier P Nieuport IV Nieuport VI Sikorsky S-10 Sikorsky S-12 Sopwith 1½ Strutter Bombers Sikorsky Ilya Muromets Voisin III Caudron G.4 Trainers Bleriot XI Morane-Saulnier L Morane-Saulnier G Nieuport IV Nieuport 10 Voisin III See also List of World War I flying aces from the Russian Empire List of Russian aviators List of Russian aerospace engineers References Sources Blume, August. The Russian Military Air Fleet in World War I, Volume One. (Schiffer Publishing, 2010). . — The Russian Military Air Fleet in World War I, Volume Two. (Schiffer Publishing, 2010) . Chant, Christopher, Austro-Hungarian Aces of World War I, Osprey Aircraft of the Aces, #46 (London: Osprey Publishing, 2002) . Durkota, Alan; Darcey, Thomas; Kulikov, Victor, The Imperial Russian Air Service: Famous Pilots & Aircraft of World War One (Mountain View, CA: Flying Machines Press, 1995) . Franks, Norman; Guest, Russell; Alegi, Gregory. Above the War Fronts: The British Two-seater Bomber Pilot and Observer Aces, the British Two-seater Fighter Observer Aces, and the Belgian, Italian, Austro-Hungarian and Russian Fighter Aces, 1914–1918: Volume 4 of Fighting Airmen of WWI Series: Volume 4 of Air Aces of WWI. Grub Street, 1997. . Palmer, Scott W. Dictatorship of the Air: Aviation