The Flitzer Z-21 or Staaken Flitzer is a British amateur-built aircraft, designed by Lynn Williams and produced by Flitzer Sportplanes of Aberdare, Wales. The aircraft is supplied as plans for amateur construction. In the late 1990s it was also marketed as plans and in kit form by Bell Aeromarine of Leicester, UK. The Z-21 is a single-seat, open cockpit 1920s-style biplane with fixed conventional landing gear with spoked wheels and a single engine in tractor configuration. The aircraft is made from wood, with its flying surfaces covered in doped aircraft fabric. Its 5.5 m (18.0 ft) span wing has a combined area of 9 m2 (97 sq ft) and ailerons on the bottom wing only. The aircraft was designed for the 65 hp (48 kW) Volkswagen air-cooled engine, but other variants have been developed that use a variety of engines, including the 110 hp (82 kW) Rotec R2800 radial engine. Further planned developments include a tandem two seater, a four aileron version and a lighter weight version. In August 2014 there were eleven Flitzers registered in the United Kingdom.
