With the prospect of a future World War 3 involving nuclear weapons, jet aircraft were purchased: 75 De Havilland Vampires in 1950, followed by over 100 De Havilland Venoms and the same number of Hawker Hunters. The Venoms served until 1983; Vampires until 1990 and Hunters even until 1994. In the late 1940s Switzerland purchased the North American P-51 Mustang from US surplus WW2 stock. The aircraft initially was intended as a stop-gap solution for the Swiss army in order to maintain a defence force during a time when the outdated Bf 109E's and Swiss built D-3801 Moranes were being phased out but the licensed production of the British designed Dh-100 Vampires and Dh-112 Venoms was not in full swing.