The BAC TSR-2 was an ambitious Cold War British strike and reconnaissance aircraft developed in the late 1950s and early 1960s. It was designed to fly at high supersonic speeds at both low and high altitude while delivering nuclear or conventional weapons deep into enemy territory. Although flight testing beginning in 1964 demonstrated impressive performance and great potential, the program became increasingly controversial due to escalating costs, political pressure, and changing defense priorities. In 1965 the British government cancelled the project despite its technical success. The TSR-2 has since become one of the most famous “what-might-have-been” aircraft in aviation history, symbolizing both the peak and the abrupt end of Britain’s independent post-war military aircraft ambitions.