"There are huge increases in efficiency by delaying the descent".
Just how much of a saving are we talking about here?
It depends on the wind, with a strong northerly and a bad combination of controller and pilot, it could add 200kgs to a planned burn of 2200kg on a medium twin jet. The longer one spends below FL 250 the greater the loss. This repeated by 3 airlines 8 times a day for 365 days, well just do the sums. And then the same going in to Glasgow.... I think it is enough of a saving to make it worth trying to do something to improve the situation. I got the impression from comments earlier in the thread that things were under discussion and some changes would be forth coming.
If there is a sea change and airlines now want maximum efficiency instead, they're going to have to accept a very much reduced capacity and the subsequent effects on their scheduling.
It is not a matter of one or the other, just a little flexibility and awareness that not all crews actually want or need to be as low as they currently are being routed. The 3 "gates" MARGO, TARTN and LANAK are too low and especially so for days with a northerly wind. Most of us know there are reasons for the "gates" but some of the reasons for those levels are not necessisarily relevant to current ATC or aircraft requirements. If they could be tweaked, even at off peak, there could be some worth while savings.
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