I can remember watching the 'live' program on the BBC.
Skip forward a few years, and the BBC were due to show a program about the air-show at Biggin Hill. At the time, it was possible to listen to the BBC TV signal on a VHF radio. We were away from home that day, but had the radio to listen to, so we found the audio from the TV signal.
We were somewhat surprised to hear about low-level flypasts and strafing runs by Jaguars and Phantoms (poss), and even live bomb-drops from a Vulcan - which we assumed was actually happening at Biggin Hill!
We later discovered that the air-show had been badly disrupted by poor weather (most of the flying was cancelled), and the Beeb had decided to re-run the 'Skywatch' program.