Siebel Si 201

The Siebel Si 201, developed in the late 1930s under the direction of Friedrich Fecher, was a pioneering German light aircraft that embodied the transition from traditional wood‑and‑fabric construction to more modern, all‑metal designs. First flown in 1939, the Si 201 originated as a testbed for aerodynamic research and as a low‑cost trainer for the Luftwaffe, reflecting Fecher’s ambition to create a versatile platform that could be produced quickly in limited factories. The aircraft featured a cantilever low‑wing monoplane layout, a retractable under‑carriage, and a compact 105‑hp Hirth HM 504 engine that delivered respectable performance – a top speed of roughly 210 km/h and a service ceiling of 5,000 m. Its mixed construction used a steel tube fuselage covered with fabric, while the wings employed aluminum ribs and stressed‑skin covering, an innovative combination for its era. Although only a handful were built before the outbreak of World II halted further development, the Si 201’s experimental data contributed to later German trainers such as the Bücker Bü 131. Today the aircraft is remembered for illustrating Friedrich Fecher’s forward‑thinking approach and for its role in advancing lightweight, efficient aeronautical engineering in pre‑war Europe.