One more wing than the German Fokker DR-1, British FK10 quadcopter from World War I
During World War I, the German army was equipped with the Fokker DR-1 triwing fighter, which was very special in the biplane era, but it did achieve certain advantages in performance, and it is also a classic model.But when it comes to multi-wing fighters, the British were very interested in a four-wing design, and today we’re going to introduce one of them, the FK10.Multi-wing fighters were nothing new at the time. Due to the power of engines and the technology of aircraft construction at the time, it was not easy to strike a perfect balance between size and maneuverability. For example, the wings of large bombers at the time were inharmonious compared with the fuselage and gave people a feeling of fragility.The need for agility meant that a large wingspan could not be used, but since a single wing could not provide the required lift, a multiwing aircraft was the natural choice.The FK10 predates the Fokker DR-1 a little bit, Armstrong.Whitworth produced a prototype and flew it in 1916.The first prototype, actually called the FK9, was designed as a two-seat fighter with four pairs of narrow wings spaced equally apart, connected by plate-like struts, and the upper wings placed forward.It is powered by a 110-hp Clerget 9Z rotor engine with twin-bladed propellers, and its rear three-point landing gear is unusual in that the main landing gear is not fully attached to the bottom wing, but to the airframe, probably because the lower wing is too far back.Two crews were mounted in front and rear, the pilot in the front and the observer in the rear. The weapons were a 303 vickers water-cooled machine gun mounted on the fuselage and a 303 Lewis machine gun operated by the observer for self-defence.Tests on the FK9 revealed that the aircraft was structurally weak and pilots needed to correct their attitude in flight, but it received an order for 50, and the production version was named the FK10.The FK10 was suitably modified to have a Clerget 9B 9-cylinder rotor engine with 130 HP output, a maximum flight speed of 135 km/h, and in-flight fuel to support the aircraft for 2.5 hours of flight.The FK10 was found to be inferior to other production models and was discontinued after only eight. Three of the FK10 were given to the Royal Naval Aviation Service for testing. These aircraft did not see the battlefield and may eventually have been scrapped.The FK10 four-wing, two-seat fighter has an air weight of 561kg, is 6.78m long and 3.51m high, with a wingspan of 8.48m and a wing area of about 36m2. It has a maximum flying speed of 135km/h and a maximum ceiling of 3,000m.