The Avro Blue Steel was a British air-launched, rocket-propelled nuclear armed stand-off missile, built to arm the V bomber force. It allowed the bomber to launch the missile against its target while still outside the range of surface-to-air missiles (SAMs). The missile proceeded to the target at high speeds up to Mach 3, and would trigger within 100 m of the pre-defined target point. Blue Steel entered service in 1963, by which point improved SAMs with longer range had greatly eroded the advantages of the design. A longer-range version, Blue Steel II, was considered, but canceled in favour of the much longer-range GAM-87 Skybolt system from the US. When that system was cancelled in 1962 the V-bomber fleet was considered highly vulnerable. Blue Steel remained the primary British nuclear deterrent weapon until the Royal Navy started operating Polaris missile armed nuclear submarines. Blue Steel was the result of a Ministry of Supply memorandum from 5 November 1954 that predicted that b. …