Breadrollaviation
You are of course quite correct here, at the NOW part of the countdown, you started the noise abatement timer. Apologies for me missing the obvious
(As a matter of interest, the 'classic' noise abatement manoevr was not so much out of LHR, but out of JFK, RWY 31L. This was really an awsome piece of flying; if you have the chance to see this one on TV, you'll see what I mean
).
Capn Bloggs
So glad you enjoyed the show. I personally think that all aircraft are amazing in their own individual way, but Concorde really WAS something else.
Dude