Slowing down on final approach.....
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Have to agree whole heartedly with Airbus Unplugged on this on!
The company SOP for the £8 of fuel saving is flap 3 on a 321, I had to ammend that to flap full in a very heavy 321 the other day as we were following a very light 319 at 2.5 miles and our Vapp was 149 with a 15Kt head which was going to screw us behind a 319 at 117 kts Vapp.
I always try to warn director of an excessivly (sp?) low or high Vapp as I do realise the problems it can cause and the potential for go arounds. However, the idea of packing in the landing train at 2.5 miles per aircraft be they 737/757/319/320/321/MD80 or even the dear old Fokker 50 and demanding we all meet the 140 after 4 is a receipe for problems.
ATC are, I'm sure, well aware of the pitfalls and I firmly believe that early communictions on director helps the cause.
As Airbus Unplugged says we are human, we are aware of the problems and we DO try our best to juggle the various variables to achieve as close to what ATC want as possible.
T'aint always gonna happen.
W2P
The company SOP for the £8 of fuel saving is flap 3 on a 321, I had to ammend that to flap full in a very heavy 321 the other day as we were following a very light 319 at 2.5 miles and our Vapp was 149 with a 15Kt head which was going to screw us behind a 319 at 117 kts Vapp.
I always try to warn director of an excessivly (sp?) low or high Vapp as I do realise the problems it can cause and the potential for go arounds. However, the idea of packing in the landing train at 2.5 miles per aircraft be they 737/757/319/320/321/MD80 or even the dear old Fokker 50 and demanding we all meet the 140 after 4 is a receipe for problems.
ATC are, I'm sure, well aware of the pitfalls and I firmly believe that early communictions on director helps the cause.
As Airbus Unplugged says we are human, we are aware of the problems and we DO try our best to juggle the various variables to achieve as close to what ATC want as possible.
T'aint always gonna happen.
W2P
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Originally Posted by AlexL
Also w.r.t the mode S comment earlier - what does your mode S show - my current IAS or my current selection in the MCP speed window?
MCP speed is not included in Mode S, and is apparently not planned to be.
Regards,
Robert
If additional holding or longer vectors with additional spacing on final is needed, you will not get any complaints from me
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In answer to the comment that it's too busy to say that you need 160 to 5 miles not 4 is a red herring. If you know that is what you need, when told to maintain a speed you can't you immediately reply (as you have to give a readback) that you need something else. As previously stated if given an instruction and you wilfully disobey it, then you are breaking the law. I know your SOPs come first, and I agree with that, after all you are sat at the sharp end, but you MUST inform if you are unable to comply with any ATC instruction. Otherwise it will lead to chaos with people choosing which instructions to comply with or not. We, as stated previously, need to work together to make it work. We don't as a general rule know every operators SOPS which is why we need to have standardisation. I try and paint a picture on the RT so that if a pilot can help they will have a full understanding of what's going on, please can we make this a 2 way process.
PS thanks to all the pilots who have helped me out over the years, I hope we're even!
PS thanks to all the pilots who have helped me out over the years, I hope we're even!
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It would be interesting to hear from aircraft designers at this point.. Are they aiming for all new aircraft to meet the need for a "standard" approach speed under all loading and weather conditions?
Sorry guys but maybe I have missed something here but surely it's quite simple - if ATC ask you to fly at an IAS then you comply if you can - if you can't comply then you advise ATC as soon as possible - why is that such a big deal?
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If ATC for example fogets to tell us to reduce speed until a defined point like f.ex. "160kt to 4DME", it is very annoying to ask all the time if we can reduce as the threshold gets closer(remember latest established in spd and glide at 500ft in VMC!).it makes obvious about back speed,isn't it?
Nemo Me Impune Lacessit
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Just a thought. On a B747-400 freighter landing at MLW of 302 tons the Vref is 157knots, so you will definitely get 160 to the marker but are you calculating on any reduction AFTER the marker or are you aware that heavy freighters won't be going much below 160kts until touchdown?
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Let us openly acknowledge that the PILOT must be able to freely choose his landing speed. Let us also acknowledge that ATC is merely trying to make things work and stuff 5 pounds of sugar into a 3 pound sack.
so, dear ATC, I would think that you should hear the word "UNABLE" more and more often and YOU should prepare for that.
during the famed berlin airlift, when the C54 was the primary plane, all the speeds were the same and you could run it like a railroad.
but now, there are a wide variety of planes and speeds.
and if ATC gives a clearance, 160knots to 4 dme, AND DOESN"T ALLOW TIME TO LISTEN for a reply, you must assume you might not get what you asked for.
I say, ATC change YOUR procedures...any speed from the FAF inbound is ok, speed adjustments only allowed prior to the FAF/OM/GS intercept.
so, dear ATC, I would think that you should hear the word "UNABLE" more and more often and YOU should prepare for that.
during the famed berlin airlift, when the C54 was the primary plane, all the speeds were the same and you could run it like a railroad.
but now, there are a wide variety of planes and speeds.
and if ATC gives a clearance, 160knots to 4 dme, AND DOESN"T ALLOW TIME TO LISTEN for a reply, you must assume you might not get what you asked for.
I say, ATC change YOUR procedures...any speed from the FAF inbound is ok, speed adjustments only allowed prior to the FAF/OM/GS intercept.
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Parabellum
It is common practice these days to ask the freighters and some specific types, e.g. B773, what their Vref is. This enables us to make some adjustment for the lack of slowdown inside 4nm.
It has been said before and bears saying again that the crux of the matter here is lack of spare runway capacity at the London airports. This lack is forcing ATC to try and make one size fit all, which of course it doesn't.
Spare capacity is not waste, it is part of essential safety management and enables ATC to allow room for individual characteristics/error. Unfortunately, the government's policy of making "best use of existing runways" works counter to good aviation practice. It is not the job of aircrew or ATC to make up for this lack but we very much feel under pressure to do so.
.4
It is common practice these days to ask the freighters and some specific types, e.g. B773, what their Vref is. This enables us to make some adjustment for the lack of slowdown inside 4nm.
It has been said before and bears saying again that the crux of the matter here is lack of spare runway capacity at the London airports. This lack is forcing ATC to try and make one size fit all, which of course it doesn't.
Spare capacity is not waste, it is part of essential safety management and enables ATC to allow room for individual characteristics/error. Unfortunately, the government's policy of making "best use of existing runways" works counter to good aviation practice. It is not the job of aircrew or ATC to make up for this lack but we very much feel under pressure to do so.
.4
Nemo Me Impune Lacessit
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Thanks 120.4, as has already been mentioned, an empty aircraft will slow down very quickly but a heavy freighter has huge inertia and needs more space.
Sympathies with the problems you have with some of the decision makers, shame they don't all have to serve an apprenticeship in ATC first!
Sympathies with the problems you have with some of the decision makers, shame they don't all have to serve an apprenticeship in ATC first!
Couldonlyaffordafiver
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126.825 (yes, it does give it away ),
I work for a large 737 operator based at EGxx (does that give it away as well
). Our management have been in discussions with yours about allowing us to fly 170 to 5 whenever possible, rather than 160 to 4, as it saves us having to drop the gear and flap 15 at eight miles.
A bit of background...
At least one 737 has been lost in the past due to a phenomenon known as "rudder hard-over". As a result, a few years ago the 737 speed schedule was changed. Before, we were able to fly 160 to 4 at Flap 5 with the gear up. In order to mitigate the "hard-over" issue, the speed schedule was increased for each flap setting to allow greater aileron authority for a given flap setting. However, the 737 has a gear warning horn which cannot be cancelled at Flap 15 (the setting needed for 160kts on the new schedule). The only solution is to drop the gear at the same time, with the consequent increase in noise and fuel burn. In fact, it almost totally negates the benefits of a CDA. At 170kts, we are able to fly at Flap 10 with the gear up.
The reason I bring this up is that it has been suggested to us that if we request 170 to 5 on first contact with your good self (126.825), it should be approved. Unfortunately I have given up as by the time I am transferred to your mate on 118.95, the request has invariably been forgotten. This happens 95% of the time. Clearly when I'm turning onto the localiser, it's a bit late to ask again - I have and it's been politely suggested to me that I request it on first contact with 126.825. It seems a bit churlish to reply, "I did!".
Anyway, my question....
As my company is responsible for a "significant" number of movements at EGxx (sorry, nearly called it LGx), is there a reason why ATC cannot plan for us to do 170 to 5 and only make us do 160 to 4 if there is a tactical reason at the time?
Not having a dig, simply curious.
Regards,
HF
PS: In 737 terms, to make our "stable approach" gate of 1000' AAL, 160 to 4, 170 to 5 and 180 to 6 equate pretty much to the same thing.
),I work for a large 737 operator based at EGxx (does that give it away as well
). Our management have been in discussions with yours about allowing us to fly 170 to 5 whenever possible, rather than 160 to 4, as it saves us having to drop the gear and flap 15 at eight miles.A bit of background...
At least one 737 has been lost in the past due to a phenomenon known as "rudder hard-over". As a result, a few years ago the 737 speed schedule was changed. Before, we were able to fly 160 to 4 at Flap 5 with the gear up. In order to mitigate the "hard-over" issue, the speed schedule was increased for each flap setting to allow greater aileron authority for a given flap setting. However, the 737 has a gear warning horn which cannot be cancelled at Flap 15 (the setting needed for 160kts on the new schedule). The only solution is to drop the gear at the same time, with the consequent increase in noise and fuel burn. In fact, it almost totally negates the benefits of a CDA. At 170kts, we are able to fly at Flap 10 with the gear up.
The reason I bring this up is that it has been suggested to us that if we request 170 to 5 on first contact with your good self (126.825), it should be approved. Unfortunately I have given up as by the time I am transferred to your mate on 118.95, the request has invariably been forgotten. This happens 95% of the time. Clearly when I'm turning onto the localiser, it's a bit late to ask again - I have and it's been politely suggested to me that I request it on first contact with 126.825. It seems a bit churlish to reply, "I did!".
Anyway, my question....
As my company is responsible for a "significant" number of movements at EGxx (sorry, nearly called it LGx
), is there a reason why ATC cannot plan for us to do 170 to 5 and only make us do 160 to 4 if there is a tactical reason at the time?Not having a dig, simply curious.
Regards,
HF
PS: In 737 terms, to make our "stable approach" gate of 1000' AAL, 160 to 4, 170 to 5 and 180 to 6 equate pretty much to the same thing.
Couldonlyaffordafiver
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Just re-read the thread to find that fingerbob has made a similar point, albeit using about a tenth of the number of words. 
Still, can we change the ATC SOP for the 737 to 170 to 5 please.
Still, can we change the ATC SOP for the 737 to 170 to 5 please.
HF, I always try give you 170kts (or at least up to 6dme), the lack of requests for 170 to 5 make me wonder if I'm doing the right thing!
Is it beneficial for all 737s at all weights?
maybe the optimum time to make the request is just before you turn base when there's a greater chance you're on the frequency that is going to provide the final approach spacing. But how do you know when that will be?
can't your ops dept speak to our ops dept and make an official request?
would your entire fleet be happy with that?
the only problem we have is, the more we tailor the speeds to suit individual aircraft and airlines, the more complex our job is. That's ok for someone that's been valid for a few years but might be an unnecessary burden on trainees.
Is it beneficial for all 737s at all weights?
maybe the optimum time to make the request is just before you turn base when there's a greater chance you're on the frequency that is going to provide the final approach spacing. But how do you know when that will be?
can't your ops dept speak to our ops dept and make an official request?
would your entire fleet be happy with that?
the only problem we have is, the more we tailor the speeds to suit individual aircraft and airlines, the more complex our job is. That's ok for someone that's been valid for a few years but might be an unnecessary burden on trainees.
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No the 737-700 doesnt need this. We can fly 160 at flaps 5 most of the time. Dontknow for the rest. Most of the time I could give you 180 to 6 as well. Being at Flap 1.
At Low weights the speeds go down very much.
The diffence between the classics and ng's is that classics have a fixed speed schedule. Where the NG's have an FMC generated Flap speed based on weight. Preferably we would like to fly our fmc generated flap speeds but this would not work for you guys.
So on a typical day in the -700 we would fly
flap1 180kts
flap5 160kts
gear down flap 15 about 145kts
gear down flap 30 about 130kts
At Low weights the speeds go down very much.
The diffence between the classics and ng's is that classics have a fixed speed schedule. Where the NG's have an FMC generated Flap speed based on weight. Preferably we would like to fly our fmc generated flap speeds but this would not work for you guys.
So on a typical day in the -700 we would fly
flap1 180kts
flap5 160kts
gear down flap 15 about 145kts
gear down flap 30 about 130kts
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QED.
One size does not fit all (even within a generic type). The Final Director only has capacity for so much flexibility and now that 2.5nm is "expected", he has less room for error too.
In an ideal world, an advanced ATC support tool would provide accurate guidance for the different pairs in the sequence, taking into account their individual Vref on the day - but that day is still some years away. In the meantime, the priority should surely be to protect the system by creating slack. It is not the job of the individuals to make compromises on good practice in order to make the numbers fit.
.4
One size does not fit all (even within a generic type). The Final Director only has capacity for so much flexibility and now that 2.5nm is "expected", he has less room for error too.
In an ideal world, an advanced ATC support tool would provide accurate guidance for the different pairs in the sequence, taking into account their individual Vref on the day - but that day is still some years away. In the meantime, the priority should surely be to protect the system by creating slack. It is not the job of the individuals to make compromises on good practice in order to make the numbers fit.
.4
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Hi!
I like to go back to the question asked in the beginning of this thread. "What gives" when given a speed restriction, when should you slow down?
When you are cleared for i.e ILS, any speed restriction are also lifted unless controller have stated a speed to maintain. All you should follow after the clearance is any restrictions decribed on the approach charts. (guess most busy airports have written something like :"maintain minimum 160kt's to OM/4-5NM...if not able to comply...report to ATC") So that means if you are turned on as an example at 25nm final you can theoretically reduce at your own descretion without doing anything wrong.
However....slowing down that early..if you are in a sequence...will probably lead to a controller who will get slightly higher pitch in his voice...and not be your best friend
Most pilots are good at reducing speed with their "brain working"...which means..about 210 on base...180 from 10 miles..and towards 160 around 4-5nm final. But sometimes you get a suprize
(remember I once called Speedbird with 757..for "Slowbird...contact TWR"..when he did reduce at 25NM to 160"....fu
ing up everything for me )
So to maintain an effective final without loosing space, controllers have to all the time specify the speed to fly at all the way.
"Turn hdg 230, Cleared ILS19R maintain speed 210 until adviced".."maintain speed 180 to 6NM"...and so on.
But to go back to beginning...unless controller tell you to maintain some speed....cleared ILS...means..you can slow down.
Regards
Final Vectors
ENOS APP
I like to go back to the question asked in the beginning of this thread. "What gives" when given a speed restriction, when should you slow down?
When you are cleared for i.e ILS, any speed restriction are also lifted unless controller have stated a speed to maintain. All you should follow after the clearance is any restrictions decribed on the approach charts. (guess most busy airports have written something like :"maintain minimum 160kt's to OM/4-5NM...if not able to comply...report to ATC") So that means if you are turned on as an example at 25nm final you can theoretically reduce at your own descretion without doing anything wrong.
However....slowing down that early..if you are in a sequence...will probably lead to a controller who will get slightly higher pitch in his voice...and not be your best friend
Most pilots are good at reducing speed with their "brain working"...which means..about 210 on base...180 from 10 miles..and towards 160 around 4-5nm final. But sometimes you get a suprize
(remember I once called Speedbird with 757..for "Slowbird...contact TWR"..when he did reduce at 25NM to 160"....fuing up everything for me )So to maintain an effective final without loosing space, controllers have to all the time specify the speed to fly at all the way.
"Turn hdg 230, Cleared ILS19R maintain speed 210 until adviced".."maintain speed 180 to 6NM"...and so on.
But to go back to beginning...unless controller tell you to maintain some speed....cleared ILS...means..you can slow down.
Regards
Final Vectors
ENOS APP
Couldonlyaffordafiver
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HF, I always try give you 170kts (or at least up to 6dme), the lack of requests for 170 to 5 make me wonder if I'm doing the right thing!
Is it beneficial for all 737s at all weights?
Is it beneficial for all 737s at all weights?
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Hey 120.4 -
Solution - find the source of the pressure, kick his butt out of the approach room and report him to CHIRP.
Beancounters cannot be trusted with safety.
It is not the job of aircrew or ATC to make up for this lack but we very much feel under pressure to do so
Beancounters cannot be trusted with safety.
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Sorry guy's 170 to 5 won't work for the 737 NG (700 anyway)
We already need to fly 160 to 4ish gear down flap 15 in order to gaurentee stability. This is at the companies direction after numerous unstable approach's with just flap 5 to 4. I doubt they'd be happy to do this at 170. Given that people tend to begin to slow shortly after 5 in any case the suggested change would in effect give us an extra 10 kts to lose in what would be a less draggy config. 160 to 5 would work for us and is the standard speed europe wide.
We already need to fly 160 to 4ish gear down flap 15 in order to gaurentee stability. This is at the companies direction after numerous unstable approach's with just flap 5 to 4. I doubt they'd be happy to do this at 170. Given that people tend to begin to slow shortly after 5 in any case the suggested change would in effect give us an extra 10 kts to lose in what would be a less draggy config. 160 to 5 would work for us and is the standard speed europe wide.