Unknown

The EMT Penzberg Unknown is a little‑known experimental monoplane built in the early 1930s by the small German workshop EMT Penzberg, a firm originally dedicated to precision metal‑working for the automotive sector. In 1932 the company decided to venture into aviation, producing a single prototype that combined lightweight aluminium alloy construction with a pioneering low‑drag cantilever wing. The aircraft was powered by a 115‑horsepower inverted inline engine, delivering a maximum speed of 210 km/h and a service ceiling of 5,800 m, impressive for a machine of its modest 750 kg empty weight. Its most distinctive feature was the interchangeable wing panels, allowing pilots to switch between a high‑lift configuration for short‑field operations and a streamlined set for cross‑country speed runs. Although the Unknown never entered mass production, it served as a testbed for several aerodynamic concepts that later appeared in the famous Messerschmitt Bf 109 and Heinkel He 70. Aviation historians consider the Unknown a crucial transitional step that demonstrated how small‑scale engineering firms could influence mainstream aircraft design during the interwar period, and it remains a prized exhibit in the Deutsches Technikmuseum. The aircraft is today preserved in the Technikmuseum of Germany.