A virtual engineering approach to the ship-helicopter dynamic interface – a decade of modelling and simulation research at the University of Liverpool

The operation of maritime helicopters to naval vessels at sea is often a difficult and dangerous task. Along with the restricted landing area and the rolling, pitching and heaving of the ship's deck, the pilot also needs to contend with the turbulent, and ‘invisible’, wake produced by the air flow over the ship's superstructure. There has been significant international research in the past decade or more to understand better the environment around the ship and how it impacts the helicopter’s handling qualities and pilot workload. Central to this research, and the consequent growth in understanding, has been the use of modelling and simulation. This paper reviews some of the research that has been carried out at the University of Liverpool where the Flight Science and Technology Research Group has developed its Heliflight-R full-motion research simulator to create a simulation environment for the launch & recovery of maritime helicopters to ships. HELIFLIGHT-R has been used to conduct flight trials to produce simulated Ship-Helicopter Operating Limits (SHOLs). This virtual engineering approach has led to a much greater understanding of how the dynamic interface between the ship and the helicopter contributes to the pilot’s workload and the aircraft’s handling qualities and will inform the conduct of future real-world SHOL trials. The paper also describes how modelling and simulation has been applied to the design of a ship’s superstructure to improve the aerodynamic flow field in which the helicopter has to operate. The superstructure aerodynamics also affects the placement of the ship’s anemometers and the dispersion of the ship’s hot exhaust gases, both of which affect the operational envelope of the helicopter, and both of which can be investigated through simulation.