Letov S-231

The Letov S‑231 was a single‑engine, low‑wing monoplane developed in the late 1930s by the Czechoslovak aircraft builder Letov Kbely. Designed as a versatile trainer and liaison aircraft, the S‑231 evolved from earlier Letov models, incorporating an all‑metal airframe and a more powerful Walter Minor IV radial engine that delivered roughly 105 hp. Its compact 9‑meter wingspan, retractable landing gear, and adjustable cockpit instrumentation made it well suited for both basic pilot instruction and advanced aerobatic work. Production began in 1939, but the outbreak of World War II curtailed large‑scale manufacturing; only a handful of airframes were completed before the German occupation forced Letov’s facilities to shift to repair work. After the war, surviving S‑231s were used by the Czechoslovak Air Force for pilot conversion training and as utility transports, demonstrating the type’s robustness and ease of maintenance. Though never produced in large numbers, the S‑231 holds a notable place in Central European aviation history as a testament to Letov’s engineering skill, bridging the gap between pre‑war biplanes and the modern monoplanes that would dominate the post‑war era.