This series of lectures recalls the achievements of that outstanding pioneer of rotary wing flight Juan de la Cierva. At around the age of 23, he began to develop the concept of improved safety in flying machines, and included in his studies the concept of the helicopter. Having carried out many tests of various possible configurations, he discarded the concept of true helicopter flight as not being achievable with the then current state-of-the-art.

However, he became convinced that his basic objectives of short takeoff and landing, and safe low speed flight could be achieved by replacing the wing of a conventional aircraft with an autorotating rotor.