Austria Hirtenberger Patronen Ziindhutchen und MetallwarenfabrikAG began aircraft manufacture in 1935 after taking over Flugzeugbau Hopfner. Only the Hirtenberger HS-9 parasol-wing training/touring monoplane was produced. An open-cockpit tandem two-seater, it had either a 125 hp Siemens or 120 hp de Havilland Gipsy Major engine, the latter variant being designated HS-9A.