The 1991 Cierva Lecture. Aberdeen and its influence on the evolution of the commercial IFR twin engined helicopter

Extract

Juan de la Cierva was born in Mosei, Spain nearly 100 years ago on 21 September 1895. At the age of 15 he constructed with two friends, a glider of his own design and contined to show great interest in aviation and aircraft design. He gained an engineering degree and in 1918 built his first tri-motor aeroplane in Spain. His concept was to provide a flying machine having a parachute capability for improved safety in the event of an engine failure and he worked in the direction of the helicopter concept, but concluded that true helicopter flight was not technically feasible with the state of the art at that time. He concentrated therefore on short take-off and landing combining both the fixed wing and the helicopters physical characteristics and called his invention the autogyro. The first successful flight with his autogyro was on January 9th 1923 at Getafe Aerodrome, Madrid. By 1925 development aircraft had achieved reliability and he began demonstrations in France, England and the United States before starting to produce the autogyro in quantity in both England and the United States. It was Juan de la Cierva's main rotor blade design and creation of the articulated rotor system that played such an important role in the first successful helicopter which flew in 1936 and in all subsequent helicopters.