Rotary wing flight was made a reality in 1923 when Spaniard aeronautical engineer Juan de la Cierva (1895-1936) flew his 'C4'. By the 1930s the auto giro became practical, with a freely turning rotor for lift and a normal propeller for thrust. In Britain, the most widely used autogiro was the C30, first flown in 1933. The C30A was a later version.
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