Yesterday evening I heard the now familiar noise of a Hercules (Canadian) some distance away (Tunbridge Wells) at 20,000 ft, Confirmed by ADS B
I have just heard the noise of a Hercules (Polish) some even further away (Tonbridge) at 20,000 ft, Confirmed by ADS B, it wasn't exactly quiet either!
It seems that you don't realy need radar for locating the Herc, just the Mk 1 EarHole. If you placed three people say a mile apart, you could triangulate the sound and that should be good enough to launch a SAM
I though the Canadian one yesterday might have been going to St Athan for maintenance, but has it got close to Brize it did one of those Khe Sanh Approaches and landed at Brize. I suspect the Poles are about to do the same thing
Edited to add - The Poles are doing a Khe Sanh into Brize. Practice for supplying forward air strips in Eastern Europe???