Alert Condition One was signalled with the codeword
Prometheus.
Now I had read the book
The Penetrators
Set in the corridors of power of the USAF's Strategic Air Command, the 1965 novel The Penetrators is the story of a maverick Royal Air Force exchange officer who leads a mock Avro Vulcan bomber attack on the USA. Replete with quotes from Curtis LeMay, Robert S McNamara and other key figures of the Cold War era, The Penetrators foreshadowed the kind of richly detailed, political-military thriller . . . The book also strongly argued the case for the US's manned long-range bomber force, which was then in danger of being phased out in favour of ICBMs.
And Gray used the same codeword. Later in the book he used
Apocalypse.
Now although
Prometheus as the Alert Condition 1 codeword was an open Secret the codewords for Scramble and Positive Release were not. Was
Apocalypse one of these codewords?
I reported this 'breach' and it was investigated. It turns out that Bomber Command had only picked
Prometheus after Gray had written his book. It was a complete coincidence.