Nieuport XI’s were first used in 1915. Their biplane design allowed them to easily outmaneuver their German Fokker Eindecker (“monoplane”) counter parts. Armed with a single 7.7 Lewis machine gun on the top wing element, the system was primed to make aces of her pilots – at least until German aircraft design caught up with this XI series. If the Nieuport XI had any drawback, it was the limited armament and the propensity of the wing assembly to buckle violently in flight, sometimes breaking apart.