Yes, it is always interesting how far the sound travels from some airports with heavy wide-bodies taking off. I remember back in the 70's BOAC/EAA/Gulf Air VC-10's heading out of LHR heading eastwards routing(Dover?). Now obviously the Vickers aircraft wasn't known for it's stealth qualities, but man alive, the sound just kept on and on and on, reverberating in the nighttime air. At times it came back stronger before ever so slowly fading away again. I thought that I'd imagined it being that the years had passed, but lo and behold some years back I heard it again at night and out of LHR and headed eastwards. It turned out to be the RAF VC-10 'Bob' on one of it's last sorties before retirement and it was exactly as I'd remembered it those decades ago. It's all the more impressive when the aircraft sound penetrates the soundsphere of a big city.