The Oberursel U.III engine is a powerful and rare twin-row rotary engine that represents a pinnacle of early aviation engineering, particularly during World War I. Developed by Oberursel, this 14-cylinder, air-cooled engine was designed to deliver approximately 160 horsepower, a significant increase over its predecessors. With a displacement of around 24.6 liters, the U.III was used to power high-performance aircraft, providing them with the power and speed needed for advanced maneuvers in aerial combat. The U.III’s innovative twin-row configuration distinguishes it from other engines of its time. By stacking two rows of seven cylinders, Oberursel effectively doubled the engine's output without a proportional increase in size, maintaining the compact design advantages of rotary engines. This made the U.III ideal for fighter planes like the Fokker D.VI and the Pfalz D.VIII, known for their agility and performance.
