Oberursel U.I

U.I
A Gnome 9 Delta, from which the U.I was copied, on display at the Musée des Arts et Métiers, Paris
Type	9-cyl Rotary piston engine
National origin	Germany
Manufacturer	Motorenfabrik Oberursel
Developed from	Gnome Delta

The Oberursel U.I was an early German aircraft engine that powered many German fighter aircraft in the first part of World War I. It was a 9-cylinder air-cooled rotary engine, a licence-built copy of the Gnome Delta that Oberursel was producing under licence before the war. It developed 75 kW (100 hp).

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