Junkers J 7

The Junkers J 7 was a pioneering German all‑metal monoplane built by Junkers Motorenbau und Junkers Flugzeugwerk in the early 1920s. Developed as a continuation of the pioneering J 1, it represented Hugo Junker’s vision of lightweight, cantilever‑wing aircraft with a fully stressed‑skin fuselage, a radical departure from the fabric‑covered biplanes that dominated World War I. First flown in 1921, the J 7 incorporated a high‑aspect‑ratio wing of thick, corrugated duralumin, a single Mercedes D.II inline engine mounted in the nose, and a fixed tailskid undercarriage. Its relatively low weight and clean aerodynamic form gave it a maximum speed of about 160 km/h and a service ceiling near 4 500 m, performance figures that impressed contemporary pilots and engineers. Though only a handful were produced, the J 7 served as a testbed for structural techniques that would later appear in the celebrated Junkers F 13, the world’s first all‑metal transport aircraft. By proving that metal construction could be both robust and economical, the J 7 helped usher in a new era of aircraft design, influencing not only German aviation but also the broader evolution of modern airliners.