XR220 would have been the second airframe to fly had it not been damaged in transit to Boscombe Down, repairs delaying its maiden flight. XR220 was fully completed and successfully performed ground engine running trials. The date of its first flight was set to be 6th April 1965, however a fault with a pump prevented a morning take-off. However, that day the TSR2 project cancellation was announced to the public by the Labour government and the aircraft was impounded before an afternoon test flight could commence.
Due to spiralling costs and the potential of ordering cheaper aircraft from America, notably the F111K, the government of the time took the decision to cancel the programme hoping to save millions of pounds in the process. Luckily for the UK the F111 order for the RAF was also cancelled, as the cost of the US-built bomber also spiralled.. The tactical strike role was left to the F4 Phantom and Buccaneer, two aircraft that had been rejected in favour of the TSR-2, and the active life of the sturdy Vulcan bomber was extended until the introduction of the Jaguar and the Tornado in the 1980's.