Concorde – An alternative view.
Pardoned PPRuNer
Joined: Jun 2001
Posts: 388
Likes: 0
From: GlassGumtree
Ahh BigNose....There is absoultely no need for me to bait you blokes in LATCC...you just jump in the boat....
But I feel you miss my point. Have a look at the various threads started by your colleagues and do yo see a trend where everything is a problem, everybody is a problem...then just like this one, someone in the know pipes up and says "no problems, why didnt you just ask" rather than taking a logical progression in problem solving it appears the first step in the LATCC change management book is to post on PPRUNE.
It is great to see our colleagues and friends the tech crews venturing into the ATC forum, esp someone as respected as a Concorde driver.
Never said I was better than anyone, just trying to better myself
But I feel you miss my point. Have a look at the various threads started by your colleagues and do yo see a trend where everything is a problem, everybody is a problem...then just like this one, someone in the know pipes up and says "no problems, why didnt you just ask" rather than taking a logical progression in problem solving it appears the first step in the LATCC change management book is to post on PPRUNE.
It is great to see our colleagues and friends the tech crews venturing into the ATC forum, esp someone as respected as a Concorde driver.
Never said I was better than anyone, just trying to better myself
Joined: Nov 2001
Posts: 171
Likes: 0
From: UK
Thanks for the +ve comments on the feedback - I personally think flight deck crews and atc have nothing like enough 2-way exchanges like this, and when we do get together it is invariably enormously useful for all of us, as this message thread shows.
BigNose - I can imagine the round-the-bay trips being a problem from atc's point of view. I think it will be a little while before these resume - and I think there will probably be a "strategy" heads-up between the fleet and atc beforehand.
O/Load - thanks for the detailed reply. Sorry about the delay in getting back - been out blowing the cobwebs off SM!!
Regarding the accel, it is essentially an all or nothing clearance we do need because we're time-limited on the afterburners, and a level-off would involve maintaining Mach. At transonic speeds (about .99-> 1.7, which is F280->F440ish)the aircraft is in a very high drag regeme (afterburners on), shock waves dancing on the wings, and whilst the aircraft is designed to handle it admirably, we get through it as quickly as possible to non-reheated stable supersonic flight above F440/M1.7 (tech. point worth noting - you can equate Mach No. with FL here - both must go up together).
We have a standard requirement to cross 15W above F430 and 20W above F450 to help with the accel planning.
Transonic vectoring carries a few technical issues making it difficult - but not impossible. It would be better to plan up a heading pre-accel and "point and squirt". We need to be clear of land by 20nm for boom considerations. Off-track traffic avoidance is no more or less inconvenient than conventional traffic, but an accel delay of 20nm+ would really start to have more serious time/fuel penalties. I take your point regarding instantaneous g/s readings, would detailed ETAs help - eg. @ Merly, Banlo, SM15W and maybe even intermediate points?
The descent planning. Well our "ideal" is a subsonic cruise at about F370 M0.95 to a top of descent based on (Ht in 000s*2 plus 12) miles at M0.93/350kts (that changoever is @ about F310). We can change those numbers tactically to suit - the bigger the change the bigger the impact it has on the ideal (obviously). But a temporary restriction of 320kts should be OK with a bit of notice. Or, say, "make your speed 320kts by OCK55d"?
F330 would not be a problem, F290 OK if you needed it (RVSM is, of course, another hair-ball - but should be with us soon: thanks for putting up with us until then!!!). A stepped descent before intercepting our "ideal" profile is available if you need it - again, please don't feel you'll offend by asking - we know your reasons are of mutual benefit
I do worry about the routing problems, though. It sounds as though there is an airspace structure problem here, our flight plan is Barix SL3 Malby G1 -> OCK STAR as you know. If this needs changing (maybe SL3 has been left behind by recent fundamental airspace changes) it possibly needs representation at a higher level. I honestly don't know what the isses here would be.
But with problems on the day, we will happily collude with you to sort it out. Please raise it on the r/t as soon as you see a problem and with notice we should be able to oblige with as little disturbance as possible.
Obviously, we could get bogged down in an infinate list of "what ifs" with all of this, so I think the bottom line has got to be please ask us if you foresee a problem and we should be able to reach a compromise tactically. It personally makes my toes curl to think that there's a perception that we need to have a red carpet treatment - what we need is to work together to everyone's benefit.
From our conversations here, I will talk to our fleet management and see if we can produce a detailed document for atcos who work with Concorde and give you a better in-depth understanding of the performance and other considerations of the aircraft which would help us work better together. Would this be useful for you?
It there's anything else I could help you with - please ask. Send me an email and I'll email you my phone number, if we need to cover more than we have already here it may be more efficient to do it 2-way - these messages could get too big to read...!
BigNose - I can imagine the round-the-bay trips being a problem from atc's point of view. I think it will be a little while before these resume - and I think there will probably be a "strategy" heads-up between the fleet and atc beforehand.
O/Load - thanks for the detailed reply. Sorry about the delay in getting back - been out blowing the cobwebs off SM!!
Regarding the accel, it is essentially an all or nothing clearance we do need because we're time-limited on the afterburners, and a level-off would involve maintaining Mach. At transonic speeds (about .99-> 1.7, which is F280->F440ish)the aircraft is in a very high drag regeme (afterburners on), shock waves dancing on the wings, and whilst the aircraft is designed to handle it admirably, we get through it as quickly as possible to non-reheated stable supersonic flight above F440/M1.7 (tech. point worth noting - you can equate Mach No. with FL here - both must go up together).
We have a standard requirement to cross 15W above F430 and 20W above F450 to help with the accel planning.
Transonic vectoring carries a few technical issues making it difficult - but not impossible. It would be better to plan up a heading pre-accel and "point and squirt". We need to be clear of land by 20nm for boom considerations. Off-track traffic avoidance is no more or less inconvenient than conventional traffic, but an accel delay of 20nm+ would really start to have more serious time/fuel penalties. I take your point regarding instantaneous g/s readings, would detailed ETAs help - eg. @ Merly, Banlo, SM15W and maybe even intermediate points?
The descent planning. Well our "ideal" is a subsonic cruise at about F370 M0.95 to a top of descent based on (Ht in 000s*2 plus 12) miles at M0.93/350kts (that changoever is @ about F310). We can change those numbers tactically to suit - the bigger the change the bigger the impact it has on the ideal (obviously). But a temporary restriction of 320kts should be OK with a bit of notice. Or, say, "make your speed 320kts by OCK55d"?
F330 would not be a problem, F290 OK if you needed it (RVSM is, of course, another hair-ball - but should be with us soon: thanks for putting up with us until then!!!). A stepped descent before intercepting our "ideal" profile is available if you need it - again, please don't feel you'll offend by asking - we know your reasons are of mutual benefit
I do worry about the routing problems, though. It sounds as though there is an airspace structure problem here, our flight plan is Barix SL3 Malby G1 -> OCK STAR as you know. If this needs changing (maybe SL3 has been left behind by recent fundamental airspace changes) it possibly needs representation at a higher level. I honestly don't know what the isses here would be.
But with problems on the day, we will happily collude with you to sort it out. Please raise it on the r/t as soon as you see a problem and with notice we should be able to oblige with as little disturbance as possible.
Obviously, we could get bogged down in an infinate list of "what ifs" with all of this, so I think the bottom line has got to be please ask us if you foresee a problem and we should be able to reach a compromise tactically. It personally makes my toes curl to think that there's a perception that we need to have a red carpet treatment - what we need is to work together to everyone's benefit.
From our conversations here, I will talk to our fleet management and see if we can produce a detailed document for atcos who work with Concorde and give you a better in-depth understanding of the performance and other considerations of the aircraft which would help us work better together. Would this be useful for you?
It there's anything else I could help you with - please ask. Send me an email and I'll email you my phone number, if we need to cover more than we have already here it may be more efficient to do it 2-way - these messages could get too big to read...!
Joined: Nov 2000
Posts: 62
Likes: 0
From: Hayling Riviera
Conc - no problem to handle in the Approach phase - however I take issue with the comment about being able to hold as long as others, but as the 1261 has been filed will say no more as the matter is subjudice!
Joined: Feb 2001
Posts: 1,064
Likes: 0
From: Hants, UK
I too remember many occasions when Conc was on the way back from Barbados on a Sunday night and was told of a 10-15 minute delay as is usual at that time.
"Er.. we can only accept one hold" came the reply.
"Roger, what is your diversion airfield or do you wish to declare an emerency?"
"Negative, we can only accept one hold. Standby."
After a pause, it transpires that the company frequency has been busy and we are informed that a 767 in the hold at BNN or somewhere has agreed to swap approach times with the Conc to save embarrassment. Not really in the spirit of things, I suppose, but if you are paying £X,000 for a seat you have the right to queue jump, don't you?
"Er.. we can only accept one hold" came the reply.
"Roger, what is your diversion airfield or do you wish to declare an emerency?"
"Negative, we can only accept one hold. Standby."
After a pause, it transpires that the company frequency has been busy and we are informed that a 767 in the hold at BNN or somewhere has agreed to swap approach times with the Conc to save embarrassment. Not really in the spirit of things, I suppose, but if you are paying £X,000 for a seat you have the right to queue jump, don't you?
Thread Starter
Joined: Dec 2000
Posts: 15
Likes: 0
From: UK
NW1
Many thanks for the info, very informative.
Just a couple more general interest questions:
How does the fuel flow compare at un-reheated supersonic cruise with subsonic cruise flows?
What sort of level (or longitude) are you back subsonic when descending inbound. On the radar it looks fairly soon after passing our boundary at 8 degrees west.
I think the best chance of helping ATC without penalising Concorde, would be
a small adjustment to the inbound route to take Concorde Barix – Numpo or once subsonic direct Numpo, (then Nigit – Ock, which is the standard routing on the Ock star from UP4), enabling it to be vectored away from the west bounds and integrated more quickly into the east bound flow.
This would help Brecon and Bristol sectors, add very little track mileage, whilst giving Concorde a higher chance of remaining at FL370 until the optimum descent point.
I’ll trawl the idea at Latcc, and if there is a consensus of opinion (between ATCO’s!) in favour , will ask the powers that be to make a formal approach to BA.
Any Bristol/Brecon/Strumble bods care to comment, I think it’s safe to remove tin hat. Doh!
A Concorde document for ATCO’s would be an excellent idea, our information on Concorde hasn’t been updated much since the aircraft was first introduced. Most of the information new trainees get is word of mouth, there is little printed material, apart from the actual train of events that have to be action once Concorde is on its way in or out.
I agree I think we’ve probably got as far as we can for now in this type of forum,
I’ve got a much clearer idea of how it behaves operationally,
Many, many thanks for your help,
overload
Many thanks for the info, very informative.
Just a couple more general interest questions:
How does the fuel flow compare at un-reheated supersonic cruise with subsonic cruise flows?
What sort of level (or longitude) are you back subsonic when descending inbound. On the radar it looks fairly soon after passing our boundary at 8 degrees west.
I think the best chance of helping ATC without penalising Concorde, would be
a small adjustment to the inbound route to take Concorde Barix – Numpo or once subsonic direct Numpo, (then Nigit – Ock, which is the standard routing on the Ock star from UP4), enabling it to be vectored away from the west bounds and integrated more quickly into the east bound flow.
This would help Brecon and Bristol sectors, add very little track mileage, whilst giving Concorde a higher chance of remaining at FL370 until the optimum descent point.
I’ll trawl the idea at Latcc, and if there is a consensus of opinion (between ATCO’s!) in favour , will ask the powers that be to make a formal approach to BA.
Any Bristol/Brecon/Strumble bods care to comment, I think it’s safe to remove tin hat. Doh!
A Concorde document for ATCO’s would be an excellent idea, our information on Concorde hasn’t been updated much since the aircraft was first introduced. Most of the information new trainees get is word of mouth, there is little printed material, apart from the actual train of events that have to be action once Concorde is on its way in or out.
I agree I think we’ve probably got as far as we can for now in this type of forum,
I’ve got a much clearer idea of how it behaves operationally,
Many, many thanks for your help,
overload
Pardoned PPRuNer
Joined: Jun 2001
Posts: 388
Likes: 0
From: GlassGumtree
767 in the hold at BNN or somewhere has agreed to swap approach times with the Conc to save embarrassment. Not really in the spirit of things, I suppose, but if you are paying £X,000 for a seat you have the right to queue jump, don't you?
Aviation is all about innovation (look it up) compromise (how do think the things actually bloody fly!) and coordination...looks like BA and the crews did all 3 three to me in this case...you blokes might try it one day.
Joined: Nov 2001
Posts: 171
Likes: 0
From: UK
surfing: Well, arrivals from JFK can load up (BGI is different, very little opportunity to carry extra). Whether you do or not is down to the same judgment (luck) as any other type - s'easy to be caught out, but just like any other type, you can burn your extra in the hold then its cards on the table time - no difference there.
What *is* different is the post-hold bit. 320kts is min-drag at landing weight, and any less piles up the drag (hence fuel flow). By 210kts the wing is really biting the breeze, and below 190kts the fuel flow is almost what it is at 1150kts. Speed can be more important than track miles for that reason.
Eye: Slot swaps (as I know you know!!) go on all the time. As long as they remain within the same company, its all fair - a flexible way of managing resources as long as it doesn't inconvenience anyone else. All the hardware and fuel is owned by the same company - it makes sense for the company to optimise the way they are used.
O/Load: A rule of thumb is that about 25% of range is lost by decelerating from M" to subsonic cruise - 33% if you do it on 3 engines.
Inbound for a subsonic cruise segment, we reduce the rate of descent at about F410, go subsonic, and descend to F370 at M0.95 to maintain. You'll see the ROD drop off around F410 - that's about the M1 point.
If you see a good solution to the routing issue - have a go at suggesting it; I'm sure it would be in all our interests to sort that one out. Let me know how you get on.
You're more than welcome - its been very interesting talking to you guys - I'd like to think we could get more face 2 face meetings organised, like latcc visits and fam. rides etc. - we work too closely to let misunderstanings develop, eh?
Thanks for the atc input - it is much appreciated (and your very professional handling of our aircraft, too - I know the fleet appreciates it both here and equally in the US).
What *is* different is the post-hold bit. 320kts is min-drag at landing weight, and any less piles up the drag (hence fuel flow). By 210kts the wing is really biting the breeze, and below 190kts the fuel flow is almost what it is at 1150kts. Speed can be more important than track miles for that reason.
Eye: Slot swaps (as I know you know!!) go on all the time. As long as they remain within the same company, its all fair - a flexible way of managing resources as long as it doesn't inconvenience anyone else. All the hardware and fuel is owned by the same company - it makes sense for the company to optimise the way they are used.
O/Load: A rule of thumb is that about 25% of range is lost by decelerating from M" to subsonic cruise - 33% if you do it on 3 engines.
Inbound for a subsonic cruise segment, we reduce the rate of descent at about F410, go subsonic, and descend to F370 at M0.95 to maintain. You'll see the ROD drop off around F410 - that's about the M1 point.
If you see a good solution to the routing issue - have a go at suggesting it; I'm sure it would be in all our interests to sort that one out. Let me know how you get on.
You're more than welcome - its been very interesting talking to you guys - I'd like to think we could get more face 2 face meetings organised, like latcc visits and fam. rides etc. - we work too closely to let misunderstanings develop, eh?
Thanks for the atc input - it is much appreciated (and your very professional handling of our aircraft, too - I know the fleet appreciates it both here and equally in the US).
Joined: Apr 2000
Posts: 210
Likes: 0
From: escaped from NERC
I suspect that Overload's suggested inbound route BARIX-NUMPO would be likely to aim the "boom" towards the South Wales coast. Whilst I don't have a problem with that, I don't think it would find "a welcome in the hillside". Of course, the option of slowing to subsonic speeds a bit earlier to mitigate the perceived problem might be acceptable if it meant that Concorde was able to maintain its optimum subsonic level/speed until closer in.
Guest
Posts: n/a
NW1,
You can probably appreciate why we have to stick to the 250/210/190 speed regime off the stack under most circumstances.
If you went much quicker you'd need more space in front which would effectively mean further lost arrival slots. One Conc arrival at standard speeds takes up about an 11 mile chunk of the final approach, a significantly faster approach would probably require much more.
I understood that EAT swopping had been stopped in the TMA by edict from above.
Feel free to get in touch anytime you want to come in for a visit, you're always welcome. Maybe you could come on the same day I show TrafficTraffic around 
Many years ago, when approach was still over at the airport, and on a lovely clear night BAW4 came back from NYC and reported visual south abeam the airfield at FL70.
"Cleared visual approach 27L" said I.
Amazing......dropped like a brick, turned final inside 4 miles and landed, all over in about 30 secs
Then the phones started ringing
WF.
What *is* different is the post-hold bit. 320kts is min-drag at landing weight, and any less piles up the drag (hence fuel flow). By 210kts the wing is really biting the breeze, and below 190kts the fuel flow is almost what it is at 1150kts. Speed can be more important than track miles for that reason.
If you went much quicker you'd need more space in front which would effectively mean further lost arrival slots. One Conc arrival at standard speeds takes up about an 11 mile chunk of the final approach, a significantly faster approach would probably require much more.
Eye: Slot swaps (as I know you know!!) go on all the time. As long as they remain within the same company, its all fair - a flexible way of managing resources as long as it doesn't inconvenience anyone else. All the hardware and fuel is owned by the same company - it makes sense for the company to optimise the way they are used.
You're more than welcome - its been very interesting talking to you guys - I'd like to think we could get more face 2 face meetings organised, like latcc visits and fam. rides etc. - we work too closely to let misunderstanings develop, eh?
Many years ago, when approach was still over at the airport, and on a lovely clear night BAW4 came back from NYC and reported visual south abeam the airfield at FL70.
"Cleared visual approach 27L" said I.
Amazing......dropped like a brick, turned final inside 4 miles and landed, all over in about 30 secs
Then the phones started ringing
WF.
Joined: Nov 2001
Posts: 171
Likes: 0
From: UK
Hi Warped
Yes - the standard speeds off the hold work fine (my feeling is that we fit fairly well into the LHR pattern - we certainly have a more flexible decelleration / energy managemnt issue than conventional types as your visual approach experience shows!!!) - the only point I was trying to make was that speeds significantly lower than standard have an out of proportion penalty - "leave OCK heading 090 speed 170kts" would be a problem on minimum flt. plan fuel. Big problem - more track miles at 210 would be better.
No, slot swaps are still used. Thing is, if you own a 737 which burns (say) and extra 30kgs of sector fuel to carry a tonne for holding at LHR and a 747 which needs an extra 500kgs to carry a tonne for holding (and gets less holding out of it) then dynamic management of EATs makes a lot of sense. Keep it within each company, and it disadvantages nobody else - just amounts to efficient use of airtime. It can be even more practical than just cash - you may have an inbound which cannot carry extra for many technical reasons, and a 757 from CDG which can carry oodles - why unecessarily (sp?) drop your NRT 747-400 into LGW at vast expense?
Yes - the standard speeds off the hold work fine (my feeling is that we fit fairly well into the LHR pattern - we certainly have a more flexible decelleration / energy managemnt issue than conventional types as your visual approach experience shows!!!) - the only point I was trying to make was that speeds significantly lower than standard have an out of proportion penalty - "leave OCK heading 090 speed 170kts" would be a problem on minimum flt. plan fuel. Big problem - more track miles at 210 would be better.
No, slot swaps are still used. Thing is, if you own a 737 which burns (say) and extra 30kgs of sector fuel to carry a tonne for holding at LHR and a 747 which needs an extra 500kgs to carry a tonne for holding (and gets less holding out of it) then dynamic management of EATs makes a lot of sense. Keep it within each company, and it disadvantages nobody else - just amounts to efficient use of airtime. It can be even more practical than just cash - you may have an inbound which cannot carry extra for many technical reasons, and a 757 from CDG which can carry oodles - why unecessarily (sp?) drop your NRT 747-400 into LGW at vast expense?
Joined: Nov 2001
Posts: 2
Likes: 0
From: UK
Numpo i cant believe its taken you so long to post, after all Concorde is one of your favourite pet hates!!
You seem to miss Overloads point, slowing to subsonic speed earlier would achieve nothing, it is the integration into the eastbound flow which is important. A routeing to Numpo once subsonic would solve many of the Radar controllers problems.
Hope the OCT is going well!!!
You seem to miss Overloads point, slowing to subsonic speed earlier would achieve nothing, it is the integration into the eastbound flow which is important. A routeing to Numpo once subsonic would solve many of the Radar controllers problems.
Hope the OCT is going well!!!
Joined: Feb 2001
Posts: 1,064
Likes: 0
From: Hants, UK
Slot-swaps: OK, yes it is OK for companies to sort out their own aircraft if they wish, but have you considered the impact upon ATC and other companies if the BA767 at FL90 at BNN suddenly is No10 in the sequence instead of No3, so all the other companies' aircraft above him have to be vectored away from the hold and descended to keep their rightful places. Late descents ensue, can cause separation difficulties and generally get in the way. My point in raising it was only to note that, contrary to some points raised hitherto in this thread, the Conc does get preferential treatment, however subtle, more often than other more 'normal' types.
Having said that, it has been interesting to see the detailed explanation of operating it from the inside. I suppose that the fam flight scheme has gone by the board??
Having said that, it has been interesting to see the detailed explanation of operating it from the inside. I suppose that the fam flight scheme has gone by the board??
