It might be something new for the most of us but does anyone know that a little over 90 years ago, a Spanish aeronautical engineer invented a very unique flying machine unseen since the start of World War II?
By: Ringo Bones
A little over 90 years ago, a Spanish aeronautical engineer invented a novel flying machine now largely confined to some dusty esoteric corner of some air and space museum. It was called an Autogiro or gyroplane and in honor of the 90th Anniversary of Juan de la Cierva’s successful first flight, I could give a little information about it here.
Juan de la Cierva, inventor of the Autogiro was born at Murcia, Spain back in September 21, 1895. His father was a noted lawyer and statesman. Juan de la Cierva though elected a member of the Spanish Parliament in 1919 and again in 1922, devoted his energies almost entirely to the invention and development of the Autogiro.
He was educated at Escuela Especial de Ingenieros de Caminos, Canales y Puertos at Madrid, where he spent six years and studied the on his own the works of F.W. Lancaster and N, Joukowski on theoretical aerodynamics. He entered a competition for military airplane designs for the government and built a biplane bomber with three engines, using an airfoil section of his own design, developed mathematically. Tested in May 1919, the plane crashed when the test pilot stalled it.
Cierva turned to rotary wing design after this experience, as a solution to the problem of safety. His first three machines were failures, but with the change made in the fourth machine, from rotor blades rigidly fixed to the hub to blades freely hinged, the first successful Autogiro became a working reality. It was flown for 200 yards on January 19, 1923, and three public flights were made on January 21, 1923 – the longest being a complete circuit of two and one-half miles in about three and one-half minutes.
Also known as “gyroplanes” and with the exception of von Baumhauer’s experimental model, from 1923 to 1939 the only single-rotor machines that flew were Juan de la Cierva’s Autogiro or gyroplanes. These were not helicopters because they couldn’t take-off vertically, or could they sustain flight without forward or descending airspeed. The rotor was tilted backward and was turned by the airstream passing through it. In the gyroplane there is no torque to be counteracted in flight, except for the slight friction in the bearings between the rotor hub and the mast. Therefore, there is no need for counteracting means or counter-rotating rotors. However, one of the first of de la Cierva’s concepts of the gyroplane from 1920 included the use of counter-rotating rotors, principally to overcome the lateral overturning forces on a rigid rotor on forward flight and to cancel gyroscopic effects that may hinder the proper operation.
By 1925, he had solved most of the problems of the Autogiro and in that year the Cierva Autogiro Company, Ltd., was formed in England, with Cierva acting as its technical director; Cierva also collaborated closely with the Autogiro Company of America after its foundation in 1929. On September 18, 1928, he flew one of his machines across the English Channel. And in 1930 he flew an Autogiro from England to Spain, giving a number of flying demonstrations in his native country. He demonstrated the Autogiro at the National Air Races in Cleveland, Ohio in 1929 and also visited the United States in 1932 and 1933.
Cierva received numerous honors for his aeronautical work, including the Daniel Guggenheim Gold Medal for 1932, the Elliot Cresson Medal of the Franklin Institute and, posthumously, the Gold Medal of the Royal Aeronautical Society of Great Britain. During the last year and a half of his life, he supported General Franco in the Spanish Civil War. Cierva was killed in a crash of an air liner at Croyden, England, on December 9, 1936. Sadly, virtually all Autogiro and gyroplane production and experimentation had all but ceased by the start of World War II.