>The early right off 09R is incredibly impressive when it's a heavy departure but by God they're noisy (!)
Indeed. Try being in a timber-framed Travelodge-type building. Some resonance! It was always interesting to note the later generation being precisely on the same track, whilst "steam and clockwork" types showed some slight variation, but enough to give variation to the noise level.
It always seemed a bit unfair to the residents below this climb-out track, that the heaviest and noisiest traffic was also some of the latest to depart.
Occasionally, someone comes on the BBC to rant about Heathrow being noisier than ever. I recall staying at "The Heston Hilton" BA training centre circa 1982, and being woken by Tridents, 1-11s, and other noisy types from early morning. I stayed in the area recently, and heard very little.