In the Years immediately following the Second World War, it became apparent that there was a lack of suitable wind tunnels in Great Britain to provide aerodynamic data at high speeds to meet all the needs of aircraft designers. The main firms had always had their own tunnels, but these were restricted in number and size because of the expense involved. Long-term research was carried out at the Royal Aircraft Establishment at Farnborough, but there was a need for a large-scale wind tunnel for more immediate development tests and especially for testing at transonic speeds.