411a
I am not known for rising to the bait on these forums but, by golly, you are driving me close. You are absolutely right... That is the whole point of the thread: I cannot do my job properly (which is to safely squeeze every ounce out of Heathrow's miserley two runway infrastructure) when air-crew do not fly the instructed speeds or advise me if they are not able to.
Please note: I am not critizising aircrew for not being able to fly the speeds but rather for telling that they will and then not doing it. That action puts me outside the law and is in danger of getting me suspended when I am already operating at minimum spacing. If the SOPs are no longer up to air-crew requirements then we must change the SOPs and accept the loss in capacity.
We operate ATC at Heathrow with a pen and the Mark 1 eyeball. We have no tools to help us. Could YOU judge when to slow down to give exactly a 2.5nm gap, when the lead aircraft in any pair crosses 4DME, with a 30kt crosswind so that one is seeing a tailwind and the other a headwind at the point they turn in, when one aircraft is a slow B757 and the other a fast A319 ... WHEN THE AIR CREW WON'T FLY THE SPEED YOU GIVE THEM ANYWAY??? AND KNOWING THAT IF YOU GET IT 0.1NM TIGHT YOU ARE ANSWEREING TO SRG?
There, I 've don it, I have finally lost my rag over this.
By the way, the UK AIP is clear, there is NO tolerance on final approach speeds - they must be flown as accurately as possible.
Sorry
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