Nigel
You may be right! I must be getting old and crinkly,... and cranky too: It appears that in my frustration I irritated the lady in the tower last night when I asked her to send around the aircraft which was 140kts at 6nm. I was most embarrassed at her complaint and gladly ate much humble pie.
I don't have so much of a problem with aircraft
starting to slow from 160kts at 5nm, in fact I have taken to giving B75s and A319s 16kts to 5 so that the air crew feel comfortable. No, my issue is with the guy who is at 145kts at 6nm having accepted 160kts to 4nm. It caused another 'dirty dive' for the other side last night in less than good conditions. Paper work is done.
GL
Thanks for the very useful insight into Airbii "tools". If I understand correctly this means that where the wind gradient is steep there is a greater chance that the A/C will slow earlier as it drops out of the wind? Have I got that right? Last night there was about a 40+kt wind at 3000' but only about 20kts at 2000'. Would that degree of gradient encourage an Airbus to slow to 140kts at 6nm? The airline' Ops guy seemed to be suggesting it would.
If this is necessary then the difficulty for us is going to be how to know when to slow you down to take account of the different requirements. How do you judge 5nm gap efficiently when traffic is going to fly different speeds? I agree with DP, we would have to allow extra space for what we cannot control and that will reduce capacity.
.4