During 1932, work had commenced on the development of a new single-engined biplane fighter aircraft, the Avia B-34, which had been designed by aeronautical engineer František Novotný. During its development, various alternative engines were considered and trialled before eventually settling upon the license-built Hispano-Suiza 12Y engine. Other improvements during the prototype stage included the adoption of an enclosed cockpit along with a revised tail and undercarriage arrangement. On 14 April 1934, the second prototype, while flown by test pilot Václav Kočí, successfully attained a Czechoslovak national speed record of . Deliveries of production aircraft to the Czechoslovak Air Force commenced in October 1935.