De Havilland DH.27 Derby

The De Havilland DH.27 Derby was a British single‑engine, two‑seat biplane developed by the de Havilland Aircraft Company in the early 1920s. Conceived in 1922 as a lightweight trainer and reconnaissance aircraft for the Royal Air Force, the Derby first flew at Stag Lane on 10 March 1923. Its wooden frame was covered with fabric, and it was powered by a 260 hp Rolls‑Royce Falcon III V‑12 engine driving a two‑blade wooden propeller. The high‑mounted, staggered wings provided good stability, while the split‑axle undercarriage allowed operation from rough field strips. Although only three prototypes were built, the Derby introduced several design elements that influenced later de Havilland types, notably the use of the Falcon powerplant and the modular fuselage layout that facilitated rapid conversion between training and observation roles. The aircraft’s modest performance—maximum speed of 120 mph, service ceiling of 15 000 ft, and a 3‑hour endurance—demonstrated the feasibility of lightweight, versatile military aircraft in the post‑World‑War I era. While it never entered mass production, the DH.27 Derby remains a key step in de Havilland’s evolution toward more successful models such as the DH.60 Moth and the later DH.89 Dragon Rapide.

de Havilland Aircraft Company

De Havilland DH.27 Derby

Classification

Production & History

Design & Classification