A few weeks ago I mentioned hearing two Chinooks some 12 miles away across SW London, from a local hilltop woodland site with great views to the NW. When high up on the downs around here I have often heard noises that sound like jet aircraft taking off but eventually concluded that it must be Brighton line trains crossing bridges or similar.
Yesterday while walking through those woods, I heard the sound every couple of minutes - looking at ADSBX, each one was coincidental with an aircraft getting airborne from 27R at Heathrow, showing as climbing out a little to the west of the M25. I measured the 27R threshold as about 17 miles away and calculated that the sound would take perhaps a minute and a half to reach me. Now pretty sure it is the aircraft and not trains; if so it does seem remarkable to be able to hear them from so far away across a noisy city. The wind wasn't even WNW, more WSW, which would have assisted with carrying the sound to me.
Last edited by treadigraph; 22nd Mar 2024 at 17:44.