In spring 1915, a decision was taken by Germany to procure fighter aircraft, because the authorities could see no other way of countering the French Morane-Saulnier armed with machine guns. The Fokker plant subsequently mounted a machine gun on one of its Type M5K monoplane aircraft. The aircraft was fitted with a synchronizer gear that allowed the gun to fire through the arc of the propeller without hitting the blades. The patent had already been granted to an engineer called Franz Schneider in July 1913 but it was apparently completely ignored by the military authorities. Fritz Heber and a colleague called Leimberger were the first to develop this concept into a serviceable system at Fokker in Schwerin – independently of synchronizer gearboxes already developed by Poplavko and Smyslov-Dybovski in Russia. Anthony Fokker personally demonstrated the aircraft which now bore the military designation E.1/15.
A short time later, on 23 May 1915, Fokker took two aircraft, the E.2/15 and the E.3/15 on a demonstration tour to the front. The order for mass production of the aircraft, now designated as the Fokker E I by the armed forces, had just been granted. Fitted with an Oberursel rotary radial engine delivering power of 59 kW, the aircraft only differed in minor details from the M5K. The plane was not ideal as a fighter aircraft, in particular because flying performance proved to be rather modest. However, its innovative weaponry meant that it was highly effective. The aircraft was also beset by a number of serious accidents which resulted in it being grounded with a temporary prohibition on takeoff. However, pilots like Oswald Boelcke and Max Immelmann quickly achieved some spectacular successes with the aircraft and any doubts about the Fokker monoplane were quickly dispelled again. Following these successes, the Austro-Hungarian Air Force also took a number of E I aircraft into service.
By the summer of 1915, Fokker had further developed the aircraft under the internal designation of M.14. This was to be fitted with a 75 kW Oberursel rotary radial engine and had a significantly reduced wing area compared with the E I. It saw action at the front as the Fokker E II from July 1915, although there was no increase in power compared with its predecessor.
Fokker then developed wings with a greater span and created the E III, which became the first German fighter aircraft to be mass-produced in large numbers. It came into service from August 1915 and offered significant advantages over the two other Fokker monoplanes, in particular a significantly improved rate of climb. However, the machine gun had a tendency to freeze up and the synchronizer gear was quick to fail when temperatures came down too low in winter or when flying at high altitudes. Nevertheless, the Fokker E III enabled the German armed forces to more or less retain their air superiority until spring 1916. The availability of suitable engines remained a significant problem because production at the Oberursel Motoren Werken was much slower than the manufacture of fuselages at Fokker. Attempts to use other engines, for example from Siemens & Halske or Goebel, were ultimately unsuccessful. Overall, it’s likely that 79 Fokker EI and E II and 258 Fokker E III aircraft were built.
The successor model to the Fokker E III, the E IV, was already being manufactured in November 1915. Fitted with a 120 kW Oberursel rotary radial engine, the aircraft had an increased span and was additionally fitted with two machine guns. Thanks to the much more powerful engine, the aircraft was significantly faster than its predecessor, although less manoeuvrable. Only a small number of E IV aircraft, in the hands of seasoned pilots, went into service. This was mainly due to the lack of availability of the 120 kW Oberursel engine caused by very slow production.
The primary significance of the Fokker E aircraft lies in their far-reaching influence on the conduct of future aerial combat. Like everywhere else, there were still no independent fighter squadrons on the German side. The newly introduced E aircraft were distributed in pairs or singly to the air squadrons where they were actually intended for fighter escort duties. However, their pilots soon developed specific fighter tactics. Pilots like Max Immelmann and Oswald Boelke developed the first tactics for fighter missions mainly in the Fokker E III and transformed aerial combat. Aerial manoeuvres like the famous “Immelmann Turn” have remained a fixed element of military flying tactics to this day. The Fokker E III enabled the German side to achieve air superiority for the first time. And this advantage was quickly expanded by concentrating these fighter aircraft in their own units in late autumn of 1915, the single-seater fighter units. The first fighter squadrons were subsequently developed from these units. The new organization made deployment of fighters particularly effective. Initially, the Western Allies had no immediate response to the “Fokker plague”, but in spring 1916 they deployed the newly developed fighter biplanes, for example the Nieuport 11 “Bebe”. These planes were more manoeuvrable and often faster than the E.III so that air superiority moved back to the Western Allies. The Fokker monoplane quickly disappeared from the front in summer 1916 to be replaced by the first German fighter biplane.
