In my new job of looking ondemand for movies I haven't seen; I found a gem.
"Castles in the Sky", made by the BBC in 2014.
It's the story of Robert Watson Watt and the development of the Chain Home system in Britain. Lots of politics and lots of radio technology.
Fine footage of a DeHavilland Dragon, an Avro Anson in flight. Fly by from a BoB Memorial flight of a Mossie and Spitfires.
BoB movie clips.
Recommended movie.