As if this site isn't littered with enough useless information already, here's a load more. Having travelled to and from the various London airports on a number of occasions, I thought it would be nice to have an up-to-date list of the various air traffic control frequencies used at them (so that whilst en-route to the airport or waiting in the lounge I could tune-in to see exactly how delayed my flight is). Using the all-knowing Google proved rather confusing as lots and lots of differing lists appeared, so I decided to compile the lists together and then take a listen to see which channels were clearly active and which were now obsolete.

The results are posted below and only those frequencies heard to be active during random monitoring sessions in October 2006 are listed. The frequencies shown in italics were listed on a number of sites (sufficient to believe that they are for real) but monitoring showed that there was no activity, so they're listed just in case! All frequencies are in MHz.

London Heathrow Airport
Approach 119.725 134.975
Radar 120.400
Tower 118.500 (Departures) 118.700 (Arrivals)
Ground 121.900 121.700
Clearance 121.975
ATIS 121.850 (Departures) 128.075 (Arrivals)

London Gatwick Airport
Approach 126.825
Director 118.950
Tower 124.225
Ground 121.800
Clearance 121.950
ATIS 136.525

London City Airport
Tower 118.075
ATIS 136.350

London Volmet
Main 135.375
North 126.600
South 128.600

Other London Airports/Frequencies
Battersea Heliport 122.900
Thames Radar 132.700 (also used as Approach for London City Airport)
London VFR 125.625 (Visual Flight Rules)
London FIS 124.600 124.750 (Flight Information Service)

So there you have it. Together with a cheap airband scanner, you now have the knowledge required to depress yourself by listening in to flight controllers and discovering exactly how late your flight really is!