FLIGHT simulators have been in use for many years as training aids and research facilities for fixed wing aircraft. Some helicopter simulators have been built for both training and research purposes but, in the main, these devices have treated the Helicopter problem by considering the aircraft as having similar characteristics, once air‐borne, to the fixed wing aircraft. Such simulators have not, therefore, been capable of simulating hover and vertical movement particularly from the visual point of view. Some helicopter research simulators have, however, been used in the United States but the limitations of these machines were such that they were never developed as training aids.