The Fokker V.7 was a prototype German fighter triplane of World War I, an attempt to improve upon the Dr.I by using the experimental Siemens-Halske Sh.III, double acting rotary engine. (A double acting rotary involved the crankshaft rotating one way, with the crankcase turning the other). To make use of the higher power and rpm, the aircraft had a four-bladed propeller of larger diameter than the Dr.I. This required longer landing gear. The rear fuselage had to be extended to compensate for the heavier engine. Four V.7 aircraft were built. V.7/I was in the fighter flyoff competition in January 1918. The performance of the V.7 was outstanding, but the engine was not ready for service. The Fokker V.7/I was converted to a Dr.I.