Junkers T 29 29 pioneered the patented Junkers "Doppelflügel" "double wing" control system - whose concept was used through to the Third Reich's Junkers Ju 87 "Stuka" dive bomber - using full span ailerons, later used for both ailerons and flaps, hinged just below the wing trailing edge and fully exposing the entire control surface cross-section to the slipstream, forming a slot between the two surfaces. In normal flight these were used as standard ailerons, but they could be lowered like flaps for landing whilst retaining the differential movement needed for lateral control. The fuselage was flat sided with rounded decking, the Junkers
Junkers J 1 end of January 1916, Junkers had been given a contract to further develop his all-metal concept, and the later Junkers J 2 single-seat fighter, which would never see frontline service, was the follow-on to the J 1. The J 2 would only bear a superficial similarity to the J 1, being more aerodynamically refined and slightly smaller in scale, yet nonetheless the two aircraft shared an essentially similar structure. It is believed that the Junkers J 1 was not flown again after January 1916. However, it survived the First World War, and was placed on static display in 1926 at