LHR ATC and mode S
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LHR ATC and mode S
Two quick questions about LHR ATC
1. I've seen it on this board before but can't find it back. Can LHR atc see the altitude you dial in in the alt preselect? Just the other day I came in LHR and got a decent clearance of I believe 9000'. I dialed the new alt in but accidently dialed something like 8700 I believe. I also got a new freq so I decided to dial the new freq before I would forget and then dial the correct alt ( bad form, I admit) but instantly the controller came back on asking me to verify the new alt. Can LHR atc see what you dial in the alt preselect window via mode S?
2. LHR atc is very good in providing track miles so you can plan a constant decent approach ( as is required) however,coming in from LAM and landing on the 09's that is almost never the case. They give the trackmiles but they ALWAYS end up more. If you don't take that into account you have a level segment. Have other people had the same experience and if so is the cda to the 09's not required?
Thanks
1. I've seen it on this board before but can't find it back. Can LHR atc see the altitude you dial in in the alt preselect? Just the other day I came in LHR and got a decent clearance of I believe 9000'. I dialed the new alt in but accidently dialed something like 8700 I believe. I also got a new freq so I decided to dial the new freq before I would forget and then dial the correct alt ( bad form, I admit) but instantly the controller came back on asking me to verify the new alt. Can LHR atc see what you dial in the alt preselect window via mode S?
2. LHR atc is very good in providing track miles so you can plan a constant decent approach ( as is required) however,coming in from LAM and landing on the 09's that is almost never the case. They give the trackmiles but they ALWAYS end up more. If you don't take that into account you have a level segment. Have other people had the same experience and if so is the cda to the 09's not required?
Thanks
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<<Can LHR atc see what you dial in the alt preselect window via mode S?>>
Yes.
<<you have a level segment>>
...from LAM until due north of LHR because the departures climb to 6000 beneath lowest useable FL. The CDA (3nm/1000 feet) to 09s will commence once clear of the SIDs and will approximate between 25 to 30nm. Unless Number 2 Director is a god there will be a short fly-level before GP intercept. (Unless things have changed since I did it, some time ago now...)
Some of the distances to touchdown used to be 'persuasive' to achieve a desired response, so yes, there was an element of artistic licence. Radar....or RADA? Dramatic Art to achieve a desired effect....
Yes.
<<you have a level segment>>
...from LAM until due north of LHR because the departures climb to 6000 beneath lowest useable FL. The CDA (3nm/1000 feet) to 09s will commence once clear of the SIDs and will approximate between 25 to 30nm. Unless Number 2 Director is a god there will be a short fly-level before GP intercept. (Unless things have changed since I did it, some time ago now...)
Some of the distances to touchdown used to be 'persuasive' to achieve a desired response, so yes, there was an element of artistic licence. Radar....or RADA? Dramatic Art to achieve a desired effect....
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talkdownmen,
Thanks for the quick answers. Your response to my first question, very clear.
My native language is not english, I sense your answer to my second question appears to me ( excuse me if I got that wrong and my second question was not meant to critise) a little sarcastic. I understand that before you start the decent you have to clear the outbound traffic, however once you finally start to decent you get the track miles to go, however, they always end up more than initially given. I'm confused because when landing on the 27's they are always accurate, not so when given the track miles to start the final decent when landing on the 09's.
Again, apologies if I misread your answer. Are you in fact saying that track miles given are not always accurate and that atc realizes that a CDA is not always possible?
Thanks
Thanks for the quick answers. Your response to my first question, very clear.
My native language is not english, I sense your answer to my second question appears to me ( excuse me if I got that wrong and my second question was not meant to critise) a little sarcastic. I understand that before you start the decent you have to clear the outbound traffic, however once you finally start to decent you get the track miles to go, however, they always end up more than initially given. I'm confused because when landing on the 27's they are always accurate, not so when given the track miles to start the final decent when landing on the 09's.
Again, apologies if I misread your answer. Are you in fact saying that track miles given are not always accurate and that atc realizes that a CDA is not always possible?
Thanks
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No sarcasm intended. Maybe English humour. If you perceive it as sarcasm I shall stop here and now.
CDAs are the ideal but not always possible for a number of reasons.
What I am saying is that (from my time doing it) if an operator was known to be 'ponderous' it may be that they be given 'approximately 20 miles' when the range more likely greater eg. maybe 24. The psychological effect usually secured prompt response and useful performance which would avoid wasted final approach spacing rather than a request from the pilot for extra miles.
w.r.t. 27s v 09s the RMA for 09 is less constrained and therefore provides more flexibility for changing the sequence in order to maximise runway capacity. Such order changes will, of course, change distances to touchdown.
As in life, if one 'dilly-dallies' one is likely to be overtaken.... (not sarcasm)
CDAs are the ideal but not always possible for a number of reasons.
What I am saying is that (from my time doing it) if an operator was known to be 'ponderous' it may be that they be given 'approximately 20 miles' when the range more likely greater eg. maybe 24. The psychological effect usually secured prompt response and useful performance which would avoid wasted final approach spacing rather than a request from the pilot for extra miles.
w.r.t. 27s v 09s the RMA for 09 is less constrained and therefore provides more flexibility for changing the sequence in order to maximise runway capacity. Such order changes will, of course, change distances to touchdown.
As in life, if one 'dilly-dallies' one is likely to be overtaken.... (not sarcasm)
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flyburg.. Talkdownman wasn't being nasty; he's a genuinely humourous guy who would not intend to offend you.. also a very good controller and a pilot too!
I too did the Heathrow job (for 31 years) and agree with my ex-colleague. CDAs are sometimes difficult to achieve from the ATC side, especially early in the morning when they use two runways for landing. It is then necessary to provide vertical separation between traffic joining both runways until they are established and one has the other in sight or radar separation exists.
I too did the Heathrow job (for 31 years) and agree with my ex-colleague. CDAs are sometimes difficult to achieve from the ATC side, especially early in the morning when they use two runways for landing. It is then necessary to provide vertical separation between traffic joining both runways until they are established and one has the other in sight or radar separation exists.
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Now you're learning sarcasm 
Seriously though (and I don't think you were?), please don't dial in the wrong altitude - it just adds to the already busy R/T.
More importantly on the Heathrow Final Director frequency (120.4 - and all other sectors in London Terminal Control, and Manchester) we can see your indicated airspeed - now that has been very enlightening many times (and a major safety enhancement!).
SA
Seriously though (and I don't think you were?), please don't dial in the wrong altitude - it just adds to the already busy R/T.
More importantly on the Heathrow Final Director frequency (120.4 - and all other sectors in London Terminal Control, and Manchester) we can see your indicated airspeed - now that has been very enlightening many times (and a major safety enhancement!).
SA
