LHR Glideslope 3.5degrees?
Theoretically speaking if the LHR Glideslope ever goes to 3.5 degrees (I believe that is a "working principle" of decision to allow 3rd runway??) would it be possible when LHR is on westerlies & LCY on easterlies that LCY inbounds could be at 2,400ft rather than 2,000ft?
(It doesn't "sound" like much difference but could make 1-2 decibels difference to people on the ground - but, given decibels are on a logarithmic scale the combination of higher LHR & LCY inbounds could well be appreciable).
Also, if both airports were on easterlies is the climb gradient/profile for LHR departures OK to allow LCY inbounds to be at 2,400ft rather than 2,000ft?