This certainly was a giant step in aeronautical engineering with it's all metal full cantilevered wings. SO advanced was it that the workers struggled to produce it in any numbers not having experience working with corigated metal. Estimates put it about 15 years before it's time.

THE FIRST JUNKERS factory design was the J 1 (Army designation El); it was known as The Tin Donkey, and only one was built. The 9th Junkers design, the J 9, appeared in October 1917, and with its 160 hp Mercedes was entered in the fighter competitions of 1918. The Army ordered it built as the Dl. Armament consisted of a pair of fixed, forward-firing Spandau guns ahead of the cockpit.

Junkers D.I
Engine: 1 x BMW IIIa 185 hp.
Wingspan: 9.00 m
Length: 7.30 m
Weight: 654 kg/834 kg
Max. speed: 185 km/h
Ceiling: 6000 m
Crew: 1
Armament: 2 x machineguns