The Eindecker's only edge in combat was the interruptor-gear that allowed its weapon to fire through the prop. Aerodynamically, it was a basket-case, the vices of which extended beyond the lack of ailerons that Al accurately cites.
Well before its time, the aircraft had a one piece "stabilator" like that employed on the F-86 decades later. Needless to say, the "feature" wasn't properly researched or engineered in 1915. This design imparted an all but uncontrollable tendency to oscillate or roller-coaster through the air as pitch control was far too sensitive, leaving pilots struggling to simply maintain a constant attitude. This is NOT a healthy characteristic in a gun platform. The Eindecker's primary successor, the Albatros, combined conventional control surfaces with the interruptor-gear and twin forward firing machine-guns, establishing a design pattern that was exhibited in just about every successful design that subsequently emerged in WW1 and for years afterward.
Great pic, Duke!{sm3}
-Moe