Klemm Kl 25

The Klemm Kl 25, produced by the German light‑aircraft firm Klemm (sometimes referred to as Klemming), was a pivotal two‑seat sport and trainer biplane of the late 1920s and early 1930s. Designed by Hanns Klemm and first flown in 1928, the aircraft embodied the philosophy of low‑power, low‑cost aviation that the company championed after World I. Its wooden fuselage and fabric‑covered wings were built around a lightweight, high‑aspect‑ratio wing planform that gave exceptional glide‑ratio and gentle stall characteristics, making it popular with flying clubs and aero‑sport enthusiasts. Power was supplied by a variety of small inline engines, most commonly the 32‑hp Haenel HFM‑2 or the 45‑hp Salmson 9Ad, allowing a cruise speed of around 130 km/h and a range of 600 km. Over 500 examples were built, with licensed production in countries such as Switzerland, the United Kingdom, and the United States, where it appeared as the Fairchild PT‑22. The Kl 25’s economical construction, reliable handling and adaptability for aerobatics helped disseminate civilian flying across Europe, and it served as a training platform for many pilots who later flew in the Luftwaffe during World II. Its legacy endures as an archetype of interwar light aircraft design.