Walter Rethel
Arado S I
The Arado S I, conceived in 1929 by the German aeronautical engineer Walter Rethel, was an ambitious attempt to provide the fledgling Reichswehr with a modern, low‑wing monoplane fighter‑reconnaissance aircraft. Rethel, already known for his work on the Albatros D.VII, applied his experience to a streamlined wooden airframe with a cantilever wing and a fully enclosed cockpit—a rarity in Germany at the time. Powered by a 260 hp BMW VI inline engine, the S I reached a maximum speed of 260 km/h and a service ceiling of 7 500 m, while its armament comprised two 7.92 mm machine guns mounted in the fuselage. Only two prototypes were completed; flight testing in 1930 revealed excellent handling and good climb performance, but structural weaknesses in the wing spars and the rapid emergence of all‑metal designs made the aircraft obsolete before series production could begin. Although the S I never entered operational service, it demonstrated the potential of low‑drag monoplane configurations and influenced later Arado types such as the Ar 65 and Ar 68. The project also cemented Walter Rethel’s reputation as a forward‑thinking designer during a pivotal era in German aviation history.
