The Oberursel Ur.II was a 9-cylinder rotary engine producing about 110 hp (82 kW). It was a German-built copy of the French Gnome Lambda, widely used on early World War I German fighters. Its light weight, reliability, and compact size made it ideal for single-seat scouting and fighter aircraft.

Aircraft powered by the Oberursel Ur.II

• Fokker E.III – the most numerous of the German Eindecker fighters.
• Fokker D.I – early biplane fighter derived from Eindecker experience.
• Fokker D.II – biplane fighter, powered by the Ur.II in early production.
• Fokker Dr.I – iconic triplane fighter; the Ur.II provided the climb rate and maneuverability that made this aircraft legendary.
• Various experimental and training aircraft – Ur.II often used in prototypes or small-scale aircraft.

Historical significance

The Oberursel Ur.II gave early German fighters the power needed to achieve temporary air superiority during the “Fokker Scourge” (late 1915 – early 1916). Its reliability, light weight, and availability made it the backbone of early German rotary-powered aircraft and a key contributor to the success of the Fokker Dr.I, one of the most agile fighters of World War I.{{freeshipping_code_1}}{{payment}}