These models are part of a large series built for wind tunnel tests to establish the best wing and body shape for the supersonic airliner project which ultimately became Concorde. The development work was carried out at the Royal Aircraft Establishment in Farnborough, Hampshire, in the 1950s. Numerous shapes were tried in exhaustive tests and it became clear that a narrow delta wing would have sufficiently low drag for high-speed cruising and still have good handling characteristics at low speed and landing. In 1962 the British and French Governments signed an agreement to develop Concorde together.