British surface-to-air missile developed during the 1950s as the UK's main air defence weapon, and was in large-scale service with the Royal Air Force.
I entered service in December 1958, the first British guided weapon to enter full operational service. The entire defence was to be handed to a longer-range missile code named Blue Envoy, but when this was ultimately cancelled, parts of its design worked into Bloodhound Mk. II.
It was a relatively large missile, which limited it to stationary defensive roles similar to the Hercules or the Soviets' S-25
The two missiles served in tandem for some time, until the shorter-range role of the Thunderbird was replaced by the much smaller and fast-acting BAC Rapier starting in 1971. Bloodhound's longer range kept it in service until the threat of bomber attack by the Soviet Union..
