Юнкерс J.1 не был первым в мире стальным самолетом, но в нем впервые удалось использовать преимущества нового материала

The sole, all-metal Junkers J-1 was always intended as a pure research aircraft with its second seat specifically set aside for a flight test observer. Thanks to its fully cantilevered wing and tail unit bereft of the need for any form of external strut or wire bracing, the J-1 was an exceptionally clean looking machine. It could be seen as the first major milestone between the wood-and-wire era and that of the modern aircraft, a transition that Junkers contributed to more than any other. This said, it must be noted that the J-1 was anything but a success in itself, as the Junkers team's approach to structural design owed far more to established bridge building, than aeronautical, practices. Built of steel, the machine was almost certainly extremely robust, but it incurred an all-up-weight penalty that almost stopped vital military financial support at the start. First flown on 12 December 1915, the J-1 was soon being evaluated against the Rumpler C I, considered to be the finest of the contemporary military two seaters. While the J-1, at 106mph, was 7mph faster than the Rumpler, it was distinctly poorer in terms of climb and agility - two very important yardsticks in the minds of military aviators then and now. Despite these shortfalls, the military decided to continue development of the Junkers all-metal monoplane series, which staggered on through the J-2 and J-7, perceived as 'disasters', before the successful emergence of the J-8/D I and J-9/CL I machines in 1918.