The safety of shipborne helicopter operation

The helicopter has been in existence, in its present form for over 50 years and it possesses a wide variety of operational use. This paper focuses on the development of the shipborne helicopter which requires controlled flight in a very complex and potentially dangerous atmospheric environment surrounding a ship's flight deck. This type of helicopter requires dedicated design features to enable appropriate missions to be successfully achieved. It is an interesting feature of the shipborne helicopter that operational problems are as important with the aircraft in contact with the deck as to flight above it. Also there are problems, which begin with extracting the aircraft to the hangar to its eventual reinsertion. The avoidance of unfavourable characteristics has, over the years, resulted in an air vehicle where the aeroelastic properties of the rotor blades govern the operation. The magnitude of the wind speeds over a ship's deck, coupled with the varying rotor speed during the engage and disengage parts of a sortie, expose the rotors to dangerous blade deflections which have, in the past, resulted in damage to the aircraft and, in severe cases, fatalities.