Of course, part of the original plan for the 24-ship loop, was that once established in the loop, all 24 aircraft would simultaneously discharge their 'Flare and Flash' pyrotechnics.
IIRC this part of the display was cancelled as Higher Authority were concerned that such an illumination appearing suddenly over SE England would be reported by the Royal Observer Corp as the flash from a nuclear detonation (this was in the depths of the Cold War) with potentially disastrous consequences.
S206
By the way, when was the 'D' notice on this episode lifted?