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In the early years of powered aviation both tractor and pusher designs were common. However, by the mid-point of the First World War, interests in pushers declined and the tractor configuration dominated such that today all propeller-driven aircraft are assumed to be tractors.

From a military perspective, the problem with single-engine tractor aircraft was that it was not originally possible to fire a gun through the propeller arc without striking the propeller blades with bullets. Early solutions included mounting guns ( rifles or machine guns) to fire around the propeller arc, either at an angle to the side — which made aiming difficult — or on the top wing of a biplane so that the bullets passed over the top of the propeller.

The first system to fire through the propeller was developed by French engineer Eugene Gilbert for Morane-Saulnier and involved fitting metal "deflector wedges" to the propeller blades of a Morane-Saulnier L monoplane. It was employed with immediate success by French aviator Roland Garros and was also used on at least one Sopwith Tabloid of the Royal Naval Air Service.

The final solution was the interrupter gear, also known as "synchronization gear", developed by Fokker and fitted to the Fokker E.I monoplane in 1915This is a list of aviation-related events from 1915: Events January January 19 First Zeppelin raid on the UK by the German Navy. February February 15 Russian Sikorsky Ilya Muromets bombers attack the Vistula-Dobrzhani area of Poland March March 7 the firs. The first British "tractor" to be fitted with synchronization gear was the Sopwith 1½ StrutterThe Sopwith 1½ Strutter was a British one or two-seat biplane multi-role aircraft of the First World War. It is significant as the first British aircraft to be designed with a synchronised machine gun and, along with the DH. 2, contributed to the ending o which did not enter service until early 1916This is a list of aviation-related events from 1916: Events January January 12 German aces Max Immelmann and Oswald Boelcke, with 8 kills, are the first pilots awarded with Pour le Merite ("the Blue Max") January 29 the second and last Zeppelin raid on Pa.

Other solutions to avoiding the propeller arc include passing the gun's barrel through the propeller's spinner (the nose of the aircraft) or mounting guns in the wings.