In message , at 06:57:18 on Sat,
17 Apr 2010, Paul Terry remarked:
It was not until the late 70s that cheap flights (often using larger,
noisier aircraft) began to have an impact, and passenger numbers
started to increase rapidly.

The only problem with that argument is that very few charter/low-cost
flights use Heathrow - it's almost entirely full service airlines.
--
Roland Perry