As the first functioning radar defence system in the world, Chain Home was developed in the late 1930s by a team led by Robert Watson-Watt, a Scottish atmospheric physicist who had previous used radio systems to study the weather.
The new OU/BBC co-production Castles in the Sky links three dramas: the scientific drama of developing a fully-functioning system in impossibly tight time scales and with a tiny budget, the political drama of appeasement versus re-armament and Watson-Watt's personal drama. Five years later it was common for men to leave home for months or years to do work about which they could not speak, even to their families, but it was not common while Chain Home was being developed and, as the film shows, the personal costs to Watson-Watt were enormous.
Castles in the Sky ends with the start of the Battle of Britain, when a working radar system was essential if Britain's small and hard-pressed fighter pilots were to stand a chance of keeping the Luftwaffe at bay. But of course, that's not anywhere near the end of the radar story, with developments continuing throughout the war and to the present day.
In these four pieces I look at different aspects of radar technology since the introduction of Chain Home.