In message , Dave Babb
writes

I recently flew from LHR, on the way up the taxi driver mentioned an
11pm curfew for flights.
From the hotel window we could see the operating runway.
It was interesting that after about 22:45 then number of inbound
flights pretty much dried up, supporting a 23:00 shut down, but there
was a queue of flights waiting to take off until pretty much 23:30.
How does this work ? Is there a grace period ? Are there exceptions
etc...

No take-offs are scheduled after 2300, but some delayed flights are
allowed to take off up to 23:30 if they are not the noisiest types of
plane. After 23:30 there are complicated quotas that permit a certain
number of aircraft movements:

http://www.dft.gov.uk/stellent/group...022757-12.hcsp


--
Paul Terry