HK AIR TRAFFIC CONTROL BLOG
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Exiting from RWY07L
Great point to illustrate what ATC is trying to do.
1st is minimising runway occupancy and ensuring separation. Ground flow patterns and expeditious taxi routes are always secondary. TWR and GMC work together as a team to achieve this and runway traffic will always have priority over ground traffic.
A7 onto V: Standard practice is to clear the aircraft onto "V hold short H, remain this frequency". Clear the next aircraft to land. Then come back to monitor the aircraft vacating. If they've progressed onto V and still moving away from the runway, they're switched to GMC. Very straight forward and a good catch point if the crew get confused in that intersection. All on the TWR frequency.
A7 onto W: If expecting W or given A hold short of W and then quickly transferred due to the short taxi, many crews come to a complete stop and change frequency. It is not uncommon to have locally based crews as well as transient ones to be on a high speed exit with half the aircraft straddling the holding point, ie not clear of the runway and with the next landing in the flare. Simply because the entire focus has shifted to ensuring they get taxiway W. Priority is the runway and separation. If you miss W, no big deal. A8 and a U turn onto B. All quite manageable and SAFE. Also ensures a continuous flow of traffic.
A8 onto A east bound. The same circumstance applies here. Aircrew vacate, most are aware of their bay and if the shortest taxi route is A8 - B7, they will prop on the high speed. All focus is out the front of the aircraft and another high percentage will come to a complete stop on the HIGH SPEED EXIT. There are many options to ATC from this position, so if we are all about safety, efficiency and retaining the movement rate, exiting onto A is the priority. Shortest taxi route is a bonus only. With tight final spacing a Go Round becomes a high probability. Just place yourself in the landing aircraft and I'm sure you'll understand where the focus should be.
A7 onto A eastbound This is the latent confliction. The landing TWR controller usually has ample separation with the aircraft vacating, instructs "A eastbound, contact GMC". Very common scenario is that aircraft vacates, comes to an excessively slow taxi speed and the next landing aircraft rolls to vacate at A8. A perfect intercept and the aircraft are on different frequencies. With minimum separation on final, the next landing, the third aircraft in the parcel, is now in the flare. Sometimes the situation develops quite quickly when it becomes apparent the second landing aircraft misses A7. GMC on the north apron can be quite complex and a high workload. ATC has strategies to handle the situation, but the overriding issue should be, when exiting and taxiing A eastbound, that you maintain a reasonable taxi speed onto A and clear the runway.
So if you miss W or A8 - B7, no problem. This is safe and expeditious to the overall runway performance. Airmanship will always provide the correct answer.
Retain some situational awareness of the traffic behind you and the mantra is land and vacate expeditiously onto A and retain a reasonable taxi speed.
Missing a taxiway and adding 60 seconds of taxi time is details in the scheme of things. Exiting in the same direction as the landing adds to gradual deceleration and not an abrupt pull up. The more compact the arrival sequence, the more the need for this discipline. To not stop or come to a crawl on a HIGH SPEED EXIT should need no amplification. The traffic in the flare is in a much more dynamic and critical phase of flight and will always be afforded priority.Shortest taxi routes are a distant second. Having said that, I would estimate they are achieved in 90% of arrivals. Unfortunately, some of that percentage is when it shouldn't have been and this reinforces a bad practice and expectation. Probably quite acceptable at 700 movements a day. WE need to change our habits to match the movement rate.
One other issue, is that ATC has a short window of opportunity to communicate with landing traffic on roll-out. If you are still in reverse thrust and at a reasonable speed, we are reluctant to transmit instructions as you decelerate. It becomes a bit of an art form as to when to pass the instructions. Other traffic can also block those opportunities as they check in on frequency.
Thank you for the post. A valuable opportunity to get our view across. If we could provide video evidence of a broad spectrum of operators at HKIA you would be amazed at the performance and lack of situational awareness being displayed.
1st is minimising runway occupancy and ensuring separation. Ground flow patterns and expeditious taxi routes are always secondary. TWR and GMC work together as a team to achieve this and runway traffic will always have priority over ground traffic.
A7 onto V: Standard practice is to clear the aircraft onto "V hold short H, remain this frequency". Clear the next aircraft to land. Then come back to monitor the aircraft vacating. If they've progressed onto V and still moving away from the runway, they're switched to GMC. Very straight forward and a good catch point if the crew get confused in that intersection. All on the TWR frequency.
A7 onto W: If expecting W or given A hold short of W and then quickly transferred due to the short taxi, many crews come to a complete stop and change frequency. It is not uncommon to have locally based crews as well as transient ones to be on a high speed exit with half the aircraft straddling the holding point, ie not clear of the runway and with the next landing in the flare. Simply because the entire focus has shifted to ensuring they get taxiway W. Priority is the runway and separation. If you miss W, no big deal. A8 and a U turn onto B. All quite manageable and SAFE. Also ensures a continuous flow of traffic.
A8 onto A east bound. The same circumstance applies here. Aircrew vacate, most are aware of their bay and if the shortest taxi route is A8 - B7, they will prop on the high speed. All focus is out the front of the aircraft and another high percentage will come to a complete stop on the HIGH SPEED EXIT. There are many options to ATC from this position, so if we are all about safety, efficiency and retaining the movement rate, exiting onto A is the priority. Shortest taxi route is a bonus only. With tight final spacing a Go Round becomes a high probability. Just place yourself in the landing aircraft and I'm sure you'll understand where the focus should be.
A7 onto A eastbound This is the latent confliction. The landing TWR controller usually has ample separation with the aircraft vacating, instructs "A eastbound, contact GMC". Very common scenario is that aircraft vacates, comes to an excessively slow taxi speed and the next landing aircraft rolls to vacate at A8. A perfect intercept and the aircraft are on different frequencies. With minimum separation on final, the next landing, the third aircraft in the parcel, is now in the flare. Sometimes the situation develops quite quickly when it becomes apparent the second landing aircraft misses A7. GMC on the north apron can be quite complex and a high workload. ATC has strategies to handle the situation, but the overriding issue should be, when exiting and taxiing A eastbound, that you maintain a reasonable taxi speed onto A and clear the runway.
So if you miss W or A8 - B7, no problem. This is safe and expeditious to the overall runway performance. Airmanship will always provide the correct answer.
Retain some situational awareness of the traffic behind you and the mantra is land and vacate expeditiously onto A and retain a reasonable taxi speed.
Missing a taxiway and adding 60 seconds of taxi time is details in the scheme of things. Exiting in the same direction as the landing adds to gradual deceleration and not an abrupt pull up. The more compact the arrival sequence, the more the need for this discipline. To not stop or come to a crawl on a HIGH SPEED EXIT should need no amplification. The traffic in the flare is in a much more dynamic and critical phase of flight and will always be afforded priority.Shortest taxi routes are a distant second. Having said that, I would estimate they are achieved in 90% of arrivals. Unfortunately, some of that percentage is when it shouldn't have been and this reinforces a bad practice and expectation. Probably quite acceptable at 700 movements a day. WE need to change our habits to match the movement rate.
One other issue, is that ATC has a short window of opportunity to communicate with landing traffic on roll-out. If you are still in reverse thrust and at a reasonable speed, we are reluctant to transmit instructions as you decelerate. It becomes a bit of an art form as to when to pass the instructions. Other traffic can also block those opportunities as they check in on frequency.
Thank you for the post. A valuable opportunity to get our view across. If we could provide video evidence of a broad spectrum of operators at HKIA you would be amazed at the performance and lack of situational awareness being displayed.
"FlightXX maintain 160kts to 4DME".
What do you actually expect by this?
160kts to 4DME then decelerate? Or 160kts to 4.7DME then decelerate?
This is not a joke or a trick question!
What do you actually expect by this?
160kts to 4DME then decelerate? Or 160kts to 4.7DME then decelerate?
This is not a joke or a trick question!
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Missing a taxiway and adding 60 seconds of taxi time is details in the scheme of things.
I guess what I was saying is two fold, the other day the north side was very busy as the single taxiway next to the terminal with single way flow is a great design (not) anyway, outbound flow was completely stuffed by the ground controller having a hard time with an A/C who had expeditiously gone down alpha eastbound as instructed by tower no doubt, she was more concerned about telling him off than giving precise instructions to get him (non local airline) to the south side.
Can we trial a standard routing to the south side to exit A7 straight onto V if clear rather than go steaming down A knowing we have to eventually get onto W or V. Even if it's only given to CX/KA something like expect taxiway V with the landing clearance, that way most of us who know HK well can keep the flow up and get away from the runway ASAP but not add to the ground traffic by becoming part if the departure ground movements. I'd rather " whiskey southbound" or "victor southbound".
And while I'm on a roll can someone change the new terminal 3rd runway complex to the ones like Heathrow and some of the US airports with the "toaster design" terminals, they're not pretty to look at but make north south airport movements a breeze compared to the current round the houses design in HK.
Does ATC have any input to the design of taxiways? CLK has the most unfriendly taxiway system around, the stopping and starting logjams associated with taxiways V & W are terrible for a so called international airport built with a clean sheet. I hope you agree you guys and girls would have it flow better if possible or at least say this wont work because of this that & the other.
Cheers
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USE of RWY 25L or 07R for Cargo and Business Jets
As a business jet operator out of Hong Kong BAC, we often debate about asking for landing on 07R or 25L for expediency. It would lessen our taxi time inbound of course, and perhaps be smoother for airport OPs in terms of not needing another runway crossing, etc. Anyways, we usually forget to ask, and with typical visibility it might be too late when we see on final if the south runway is clear.
The question is, is it any problem for us to ask in general once approaching the terminal area for use of this runway? What is the first controller you would recommend requesting it to? (HK Director?)
HK ATC assumes all Cargo and Business traffic parking in the Business Aviation Centre prefers the southern RWY 07R/25L. During peak periods when there is excessive airborne holding, the south runway will be allocated to specific callsigns by the flow controller to land traffic ASAP. In all other circumstances, it is the prerogative of the TWR controller to assess the impact on departing traffic. i.e. if there is a gap in departures or very light traffic, we will coordinate for specific callsigns to be OFFERED that runway. It is a complex calculation with many variables. All of these are unknown to landing traffic. If ATC gets it wrong and we've offered the runway to a business jet, and as that aircraft checks in on final, there are six aircraft at the holding point and another 4 joining the queue, the resultant loss to the industry is perhaps a 3 minute delay to the first departure. Realistically though it must apply to all traffic in the queue. So in this case one business jet can incur a cumulative 30 minute loss to the industry. ATCs, through considerable experience of unstable approaches, are advised not to offer the southern runway to traffic inside 30NM from touchdown. The ideal is 50NM, but practically it is very difficult to forecast the departure queue at that range. All a poor Human Factors exercise with ATC aiming to please and crews being disrupted during high work load. Many crews will say they can handle it and brief both runways in anticipation, but there is an ample body of evidence that it can go wrong.
UNLESS YOU ARE SUBJECT TO AN EMERGENCY OR HAVE A MEDICAL EMERGENCY ON BOARD, PLEASE DO NOT ASK FOR THE SOUTHERN RUNWAY
What is the closest to the runway that you are allowed to issue a sidestep if requested?
A sidestep in HK is limited to a specific manoeuvre, not just a change of runway from one to the other. It is only used in reference to traffic when they are established on final on the Northern runway and it subsequently becomes unusable at short notice. VMC must exist for the sidestep to occur and it has a maximum distance when it has to be allocated by and a minimum distance when to be established on the Southern runway. By definition, as the sidestep is in progress at around 5NM, ATC is inducing an unstable approach scenario under the guise of a visual approach. It has been done once in my recollection with a CX aircraft on a clear blue day and well over 5 years ago. I think the airline industry in general frowns on this sort of late change with risk/reward analysis. As mentioned in the answer to the previous question, our instructions on offering an alternative runway should be by 30NM from touch down at the latest. ATC when dealing with business jet crews are always dealing with an unknown commodity in regards to capability and airfield/airspace familiarity. The vast majority of HK ATCs do not have live or regular experience in controlling such manoeuvres. It is in our manual, but it is to prevent a go round when short notices unforeseen circumstances cause a runway blockage. It is not intended as a last minute change for expedition.
Last comment is of course that professionalism prevails and we won't bother with a request at a time when the radio is so crammed as to be impractical.
Your points about eliminating a runway crossing and shortest taxi route are an ATC consideration, but similar to the situation in the post above about vacating the landing runway, these are two low priority issues.
So in summary if the south runway suits minimal delay to departing traffic, and there is no evidence of turbulence or wind-shear (local experience dictates that crews prefer the Northern runway during these conditions) we will initiate the allocation. During peak arrival periods it can be directed to any Cargo, BAC or South Apron parking traffic by the flow controller. In either case the reason will be transparent to you. As stated above, we automatically assume you prefer it. By asking you may lure an unsuspecting controller into thinking they are doing the right thing and initiate it. If this occurs, crews WILL make it habit forming. It is genuinely counter productive for the request to come from aircrew.
Once again, thanks for the question. Much better to sort issues here than on frequency.
The question is, is it any problem for us to ask in general once approaching the terminal area for use of this runway? What is the first controller you would recommend requesting it to? (HK Director?)
HK ATC assumes all Cargo and Business traffic parking in the Business Aviation Centre prefers the southern RWY 07R/25L. During peak periods when there is excessive airborne holding, the south runway will be allocated to specific callsigns by the flow controller to land traffic ASAP. In all other circumstances, it is the prerogative of the TWR controller to assess the impact on departing traffic. i.e. if there is a gap in departures or very light traffic, we will coordinate for specific callsigns to be OFFERED that runway. It is a complex calculation with many variables. All of these are unknown to landing traffic. If ATC gets it wrong and we've offered the runway to a business jet, and as that aircraft checks in on final, there are six aircraft at the holding point and another 4 joining the queue, the resultant loss to the industry is perhaps a 3 minute delay to the first departure. Realistically though it must apply to all traffic in the queue. So in this case one business jet can incur a cumulative 30 minute loss to the industry. ATCs, through considerable experience of unstable approaches, are advised not to offer the southern runway to traffic inside 30NM from touchdown. The ideal is 50NM, but practically it is very difficult to forecast the departure queue at that range. All a poor Human Factors exercise with ATC aiming to please and crews being disrupted during high work load. Many crews will say they can handle it and brief both runways in anticipation, but there is an ample body of evidence that it can go wrong.
UNLESS YOU ARE SUBJECT TO AN EMERGENCY OR HAVE A MEDICAL EMERGENCY ON BOARD, PLEASE DO NOT ASK FOR THE SOUTHERN RUNWAY
What is the closest to the runway that you are allowed to issue a sidestep if requested?
A sidestep in HK is limited to a specific manoeuvre, not just a change of runway from one to the other. It is only used in reference to traffic when they are established on final on the Northern runway and it subsequently becomes unusable at short notice. VMC must exist for the sidestep to occur and it has a maximum distance when it has to be allocated by and a minimum distance when to be established on the Southern runway. By definition, as the sidestep is in progress at around 5NM, ATC is inducing an unstable approach scenario under the guise of a visual approach. It has been done once in my recollection with a CX aircraft on a clear blue day and well over 5 years ago. I think the airline industry in general frowns on this sort of late change with risk/reward analysis. As mentioned in the answer to the previous question, our instructions on offering an alternative runway should be by 30NM from touch down at the latest. ATC when dealing with business jet crews are always dealing with an unknown commodity in regards to capability and airfield/airspace familiarity. The vast majority of HK ATCs do not have live or regular experience in controlling such manoeuvres. It is in our manual, but it is to prevent a go round when short notices unforeseen circumstances cause a runway blockage. It is not intended as a last minute change for expedition.
Last comment is of course that professionalism prevails and we won't bother with a request at a time when the radio is so crammed as to be impractical.
Your points about eliminating a runway crossing and shortest taxi route are an ATC consideration, but similar to the situation in the post above about vacating the landing runway, these are two low priority issues.
So in summary if the south runway suits minimal delay to departing traffic, and there is no evidence of turbulence or wind-shear (local experience dictates that crews prefer the Northern runway during these conditions) we will initiate the allocation. During peak arrival periods it can be directed to any Cargo, BAC or South Apron parking traffic by the flow controller. In either case the reason will be transparent to you. As stated above, we automatically assume you prefer it. By asking you may lure an unsuspecting controller into thinking they are doing the right thing and initiate it. If this occurs, crews WILL make it habit forming. It is genuinely counter productive for the request to come from aircrew.
Once again, thanks for the question. Much better to sort issues here than on frequency.
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Why doesn't HK use 07L for departures and 07R for arrivals? Surely this would cut down immensely on the ground traffic heading for the BAC and the cargo apron. BAC & cargo A/C could depart 07R when a gap was available and if not cross via K4/K1 (G/S fluctuations noted) & N to depart from 07L, thereby not interfering with any other flows.
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ATCs, through considerable experience of unstable approaches, are advised not to offer the southern runway to traffic inside 30NM from touchdown. The ideal is 50NM, but practically it is very difficult to forecast the departure queue at that range.
And while I'm on a roll can someone change the new terminal 3rd runway complex to the ones like Heathrow and some of the US airports with the "toaster design" terminals, they're not pretty to look at but make north south airport movements a breeze compared to the current round the houses design in HK.
Its about retail man!
The aeroplanes are just a way of getting everyone into the same shopping mall. They're shopping centre managers.
Of course they don't want toast rack type layout. The new Terminal will be just like the current with a Y at the eastern end as well. So we can have blocked pushbacks at both ends in future.
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Originally Posted by SMOC
Why doesn't HK use 07L for departures and 07R for arrivals? Surely this would cut down immensely on the ground traffic heading for the BAC and the cargo apron. BAC & cargo A/C could depart 07R when a gap was available and if not cross via K4/K1 (G/S fluctuations noted) & N to depart from 07L, thereby not interfering with any other flows.
If not, then a quote from the Jepp HK Airport Briefing plate might answer your question.
1.7.2.2. EASTERLY THROUGH SOUTHWESTERLY WINDS
When prevailing winds are from the East through Southwest and with a speed in
excess of 15 KT, significant windshear and moderate turbulence can be expected on the approaches to or on departure from both RWYs. Larger magnitude of windshear and turbulence is possible when the wind speed is in excess of 30 KT. Because of the closeness to the hills of Lantau, the windshear and turbulence are more significant over the southern RWY (RWY 07R/25L).
When prevailing winds are from the East through Southwest and with a speed in
excess of 15 KT, significant windshear and moderate turbulence can be expected on the approaches to or on departure from both RWYs. Larger magnitude of windshear and turbulence is possible when the wind speed is in excess of 30 KT. Because of the closeness to the hills of Lantau, the windshear and turbulence are more significant over the southern RWY (RWY 07R/25L).
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You seriously think its about the aeroplanes SMOC???
Have you ever done some approaches onto 07R with winds which have a southerly component?
HK can't help but cry wolf on every ATIS it says significant Windshear forecast 120/7
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While the wind characteristics can play a part very occasionally, the runway operating policy of departures on the south and arrivals on the north is primarily to ensure independent operations under the vast majority of conditions.
The ICAO guidance for independent parallel runway operations recommends 30 degrees divergence between a departure from one runway and the missed approach track of an arrival on the other.
Due to the terrain around CLK, we are limited to 15 degrees divergence, if an acceptable minima/climb gradient is catered for, however the runway spacing at CLK is approximately twice that required in the guidance.
A safety case was carried out, based on, in simple terms, twice the initial spacing and half the divergence, (its not quite that simple obviously when determining the tolerances, especially in the MAP phase). The risk was shown to be no worse than the ICAO guidance.
Obviously if we reversed the runway operations we suddenly have a situation where the south runway MAP has to be straight ahead due to Lantau and every departure off the north runway would have to turn away to the north and somehow get back south at some stage. Off 07 that would be up the Tai Lam gap and off 25 you would head up the PRD- but to no-mans land.
Once the PRD airspace is sorted, well........ Don't call us, we'll call you.
The ICAO guidance for independent parallel runway operations recommends 30 degrees divergence between a departure from one runway and the missed approach track of an arrival on the other.
Due to the terrain around CLK, we are limited to 15 degrees divergence, if an acceptable minima/climb gradient is catered for, however the runway spacing at CLK is approximately twice that required in the guidance.
A safety case was carried out, based on, in simple terms, twice the initial spacing and half the divergence, (its not quite that simple obviously when determining the tolerances, especially in the MAP phase). The risk was shown to be no worse than the ICAO guidance.
Obviously if we reversed the runway operations we suddenly have a situation where the south runway MAP has to be straight ahead due to Lantau and every departure off the north runway would have to turn away to the north and somehow get back south at some stage. Off 07 that would be up the Tai Lam gap and off 25 you would head up the PRD- but to no-mans land.
Once the PRD airspace is sorted, well........ Don't call us, we'll call you.
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Hmmm, not a lot I'm afraid. Certainly not PRD-wise.
Everybody working flat out on the new radar system.
We were expecting to move into our new Centre soon but .....get someone to translate the Apple Daily for you. They seem to know even more than we do.
Minor change to the CANTO and SIERA STARs coming in May. Crossing height at MURRY lowered. A window now F110/130. Know the 744 and 777 guys don't care but the hard F130 kills the 330 guys and the -8 struggles a bit too apparently. Especially if you get slowed on first contact with APP - which is only like, 99% of the time.
You should see the AIP Supps come out shortly.
We're consistently getting close to or over 1100 flights a day now into HKIA. Will go close to 1200 over Easter. Growth still running at 6% pa as of last month.
700 odd overflights as well. LCCs in the region have exploded this past 12 months.
PS. And yes, 3RS operations predicated on airspace issues being resolved satisfactorily by early 2020s. Once 3RS is in, you will go up the Tai Lam gap off the Centre runway to head north.
Everybody working flat out on the new radar system.
We were expecting to move into our new Centre soon but .....get someone to translate the Apple Daily for you. They seem to know even more than we do.
Minor change to the CANTO and SIERA STARs coming in May. Crossing height at MURRY lowered. A window now F110/130. Know the 744 and 777 guys don't care but the hard F130 kills the 330 guys and the -8 struggles a bit too apparently. Especially if you get slowed on first contact with APP - which is only like, 99% of the time.
You should see the AIP Supps come out shortly.
We're consistently getting close to or over 1100 flights a day now into HKIA. Will go close to 1200 over Easter. Growth still running at 6% pa as of last month.
700 odd overflights as well. LCCs in the region have exploded this past 12 months.
PS. And yes, 3RS operations predicated on airspace issues being resolved satisfactorily by early 2020s. Once 3RS is in, you will go up the Tai Lam gap off the Centre runway to head north.
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SMOC REPLY
1. Runway allocation - please come and visit ATC. You need to see 20 or 30 aircraft being considered at a time. Workload simply does not permit devoting perfect handling to individual aircraft.
Not all TWR controllers will assign the South Runway, because if they get it wrong, it can cause significant delays to departures. Simply looking out the cockpit will never give you the 'picture'. For example, today's departure restrictions: Routes V1-V3 +3 minutes , V4 -V5 +3 mins PECAN +4 mins and BEKOL +5. So two taxiways of 15-20 aircraft all staggered in the correct sequence so we can release departures with absolute minimum delay. Then BEKOL changed to +15 minutes. The entire sequence needed to be reset. Aircraft needed to be taken onto the runway and taken upstream to the outbound flow. Then the departures were altered for a composite V1-V5, 2 minutes alternating to 4 minutes and BEKOL back to +10. Another complete reset. So if you happen to land and see no traffic at the hold, there is every possibility that while you were in the flare on 07L that a complete parcel of departures was able to be released and three of them were all critical set course requirements. Put you on a 7NM final 07R and that can't happen. The two GMC positions are always trying to thread aircraft to the holding point with 2 and 3 minute slot windows. This is always transparent to traffic lined up in a queue. So as a runway controller, if you see considerable set course restrictions on outbound traffic, to assign landings to the SOUTH runway, is anti team work and can have drastic consequences for traffic into China or Taiwan if they miss a slot. The coordination process to re-negotiate can involve several controllers, plus incurring a similar impact on any neighbouring ATC unit. Just for one departure. So please don't think surveying a runway gives you the 'picture'.
2. Taxiway exits and instructions: Some explanation of how ATC works. We use segregation of airspace or areas of jurisdiction. It's the same on an airfield as it is in the TMA and En-Route Sectors. Generally speaking we don't talk to each other as it escalates workload dramatically. All interfaces between controllers have very strict protocol for what you can and can't do to avoid coordination. For the case you've mentioned, of vacating from A7, generally, you will be issued taxiway V. This is a standard release of that taxiway from Ground to Tower. GMC is obligated not to infringe it whenever it may be used by exiting traffic. All other traffic not proceeding to the South apron, is issued taxiway A eastbound. This ensures traffic remains separated during the handoff from one controller to the other.
HKIA has insufficient parking bays. What you may not be fully aware of, even though you see them, is the towing arrangements. Generally each hour the GMC's combined will handle between 20 to 30 tows. We give the instructions via our strip system and those are passed to the tractor driver, in Cantonese via a separate radio network. To thread them, generally in the opposite direction to taxiing traffic, can be very time consuming to minimise the impact on in -service aircraft. Delay a tow more than 30 minutes and the company will be on the phone asking its whereabouts. Common practice is to run tows on one taxiway and live traffic on another. Cross field tows will then generally run on V and all live traffic on W. So the simple exit and join V no longer applies.
During Single runway operations, we totally reverse the use of taxiway V and W from dual runway ops. We also have 5 narrow body bays below the TWR that exit directly onto V. These are practically invisible to the GMC positions due to the physical size of the TWR. When these are in use, they also impact how V is handled.
I hope you get my point. There is almost never, a standard way to operate the inter-relationship between TWR and GMC and the use of V. What ATC does do in-house is to give priority to runway traffic. So taxiways A and V are GENERALLY kept clear to allow traffic to land and exit asap and get handed off a dedicated GMC. Any protracted discussion between GMC and TWR is highly undesirable and counter productive. Generally this applies to any pairing of controllers. Coordination is generally last resort. Procedures should eliminate the vast majority. Almost all coordination in the radar environment is 'silent', done using electronic symbology with dedicated meanings.
3. What you want and what the industry demands: What you can accept and what you think your mates can accept is unfortunately not a sound model to run close to maximum movements by. It generally costs time and dramatically increases risk. With one freighter getting the South runway and if it were to impact 6 or more departures the cumulative time loss to the industry can approach 30 minutes with just one landing. Any ATC in a month will observe literally 1000's of flights. 100's of 1000's of flights over a year. What you see or hear during 5 minutes on an ATC frequency is not necessarily representative of as sound assessment of what works and what doesn't. You may well a have an understanding how actions impact you, but not 15 other aircraft. This has nothing to do with status, but aircrew consider ONE aircraft where ATC has to consider numerous aircraft. At 1000+ flights a day, ATC has to provide a safe, predictable and repeatable model to allow traffic to arrive and depart in. Ad hoc and ad lib, has little place in high movement rates. The repercussions go right through the system and invariably impact safety. Having said that, sometimes ATC has to 'make it up' to make it work. We are invariably on increased alert when we do something non-standard.
4. Procedures and where they come from: The majority of our procedures are dictated to us from consultative processes between CAD and the Airline industry. Switching runways at 10NM does not meet any TEM model we know of. ATC obviously is certainly not immune from mistakes and poor judgement, but aircrew need to comprehend the numerics of keeping 33 departures and 33 arrivals moving per hour without integrated flow management, plus all the repositioning of ground traffic, 600+ daily though area flights and the impact they have on virtually every flight into and out of HKIA, all ticking over with the least average delay to all traffic. This is not a simple exercise.
Hopefully this forum will allow us to share with you that what looks simple to you, is in fact quite complex. Do we need to change our procedures and constantly review? Absolutely, but just pitching endless criticisms at current operations without all the facts or understanding the implications of altering traffic patterns wont help.
Not all TWR controllers will assign the South Runway, because if they get it wrong, it can cause significant delays to departures. Simply looking out the cockpit will never give you the 'picture'. For example, today's departure restrictions: Routes V1-V3 +3 minutes , V4 -V5 +3 mins PECAN +4 mins and BEKOL +5. So two taxiways of 15-20 aircraft all staggered in the correct sequence so we can release departures with absolute minimum delay. Then BEKOL changed to +15 minutes. The entire sequence needed to be reset. Aircraft needed to be taken onto the runway and taken upstream to the outbound flow. Then the departures were altered for a composite V1-V5, 2 minutes alternating to 4 minutes and BEKOL back to +10. Another complete reset. So if you happen to land and see no traffic at the hold, there is every possibility that while you were in the flare on 07L that a complete parcel of departures was able to be released and three of them were all critical set course requirements. Put you on a 7NM final 07R and that can't happen. The two GMC positions are always trying to thread aircraft to the holding point with 2 and 3 minute slot windows. This is always transparent to traffic lined up in a queue. So as a runway controller, if you see considerable set course restrictions on outbound traffic, to assign landings to the SOUTH runway, is anti team work and can have drastic consequences for traffic into China or Taiwan if they miss a slot. The coordination process to re-negotiate can involve several controllers, plus incurring a similar impact on any neighbouring ATC unit. Just for one departure. So please don't think surveying a runway gives you the 'picture'.
2. Taxiway exits and instructions: Some explanation of how ATC works. We use segregation of airspace or areas of jurisdiction. It's the same on an airfield as it is in the TMA and En-Route Sectors. Generally speaking we don't talk to each other as it escalates workload dramatically. All interfaces between controllers have very strict protocol for what you can and can't do to avoid coordination. For the case you've mentioned, of vacating from A7, generally, you will be issued taxiway V. This is a standard release of that taxiway from Ground to Tower. GMC is obligated not to infringe it whenever it may be used by exiting traffic. All other traffic not proceeding to the South apron, is issued taxiway A eastbound. This ensures traffic remains separated during the handoff from one controller to the other.
HKIA has insufficient parking bays. What you may not be fully aware of, even though you see them, is the towing arrangements. Generally each hour the GMC's combined will handle between 20 to 30 tows. We give the instructions via our strip system and those are passed to the tractor driver, in Cantonese via a separate radio network. To thread them, generally in the opposite direction to taxiing traffic, can be very time consuming to minimise the impact on in -service aircraft. Delay a tow more than 30 minutes and the company will be on the phone asking its whereabouts. Common practice is to run tows on one taxiway and live traffic on another. Cross field tows will then generally run on V and all live traffic on W. So the simple exit and join V no longer applies.
During Single runway operations, we totally reverse the use of taxiway V and W from dual runway ops. We also have 5 narrow body bays below the TWR that exit directly onto V. These are practically invisible to the GMC positions due to the physical size of the TWR. When these are in use, they also impact how V is handled.
I hope you get my point. There is almost never, a standard way to operate the inter-relationship between TWR and GMC and the use of V. What ATC does do in-house is to give priority to runway traffic. So taxiways A and V are GENERALLY kept clear to allow traffic to land and exit asap and get handed off a dedicated GMC. Any protracted discussion between GMC and TWR is highly undesirable and counter productive. Generally this applies to any pairing of controllers. Coordination is generally last resort. Procedures should eliminate the vast majority. Almost all coordination in the radar environment is 'silent', done using electronic symbology with dedicated meanings.
3. What you want and what the industry demands: What you can accept and what you think your mates can accept is unfortunately not a sound model to run close to maximum movements by. It generally costs time and dramatically increases risk. With one freighter getting the South runway and if it were to impact 6 or more departures the cumulative time loss to the industry can approach 30 minutes with just one landing. Any ATC in a month will observe literally 1000's of flights. 100's of 1000's of flights over a year. What you see or hear during 5 minutes on an ATC frequency is not necessarily representative of as sound assessment of what works and what doesn't. You may well a have an understanding how actions impact you, but not 15 other aircraft. This has nothing to do with status, but aircrew consider ONE aircraft where ATC has to consider numerous aircraft. At 1000+ flights a day, ATC has to provide a safe, predictable and repeatable model to allow traffic to arrive and depart in. Ad hoc and ad lib, has little place in high movement rates. The repercussions go right through the system and invariably impact safety. Having said that, sometimes ATC has to 'make it up' to make it work. We are invariably on increased alert when we do something non-standard.
4. Procedures and where they come from: The majority of our procedures are dictated to us from consultative processes between CAD and the Airline industry. Switching runways at 10NM does not meet any TEM model we know of. ATC obviously is certainly not immune from mistakes and poor judgement, but aircrew need to comprehend the numerics of keeping 33 departures and 33 arrivals moving per hour without integrated flow management, plus all the repositioning of ground traffic, 600+ daily though area flights and the impact they have on virtually every flight into and out of HKIA, all ticking over with the least average delay to all traffic. This is not a simple exercise.
Hopefully this forum will allow us to share with you that what looks simple to you, is in fact quite complex. Do we need to change our procedures and constantly review? Absolutely, but just pitching endless criticisms at current operations without all the facts or understanding the implications of altering traffic patterns wont help.
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Psycho. Pls keep up the good work and fair play for all your articulate and intelligent efforts in posting here. One question:- where and when can I get on one of these ATC tours ? For various reasons ( industrial in nature ) I didn't do one on my command course and would have a genuine interest ( vested admittedly ) in seeing how you guys go about your daily work. Pls feel free to pm if nec.
Cheers.
Cheers.
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So please don't think surveying a runway gives you the 'picture'.
All info much appreciated. Cheers
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Question on vectoring VS remaining on own navigation - answers embedded
First of all what a great blog you got now, with a lot of great info for us pilots. Thanks for that.
I have a few questions for you.
1.Quits(sic) often we seem to be radar vectored on both arrival and departure along the STAR or SID +\- less than 1 mile. Are your aircraft separation less when radar vectored compare to on SID/ STAR or what is the reason. Separation in both cases is a standard 3nms. Wouldn't it be easier to use speed and stay on the SID/STAR? It would appear so but we’re learning that it is strongly influenced by individual interpretation. There is a proverb in ATC that states a controller’s interventions per sector, is proportional to that controller’s trust in the system and the consequences of any breakdown (system, here, refers to equipment, the airspace structures and procedures, and ability of aircrew to accurately comply). As a formula: Interventions = Consequences / Trust, you can deduce that as a sector becomes more congested, the risk of Consequences from non-compliance will increase and, assuming Trust remains constant, then the number of ATC Interventions will increase. If Trust decreases, then Interventions soars.
2. On approach we tend to get " speed (ect 210) or greater. Would you normally want us to keep high speed or slowdown towards this speed? Rather than giving you a specific (fast) speed, the controller is affording you three options: 1) keep your present speed, 2) come back to the minimum stated or 3) anything in between. By giving this clearance, the controller doesn’t foresee any consequences from either action. Please note: we are using this clearance because so many operators now, don’t like flying fast inside APP/FAD airspace. The standard ATC speeds are: 280kts in descent, 250kts at 10000’, 210kts on downwind, 180kts on base and 160kts to final, thus when we use “***kts or greater” we’re referring to those standard speeds and want you to go as fast as your company allows.
3. Now the season with weather is upon us, and we need weather deviation. Some time we just need less than 1 mile to get around a TCU. Can we " just " get around it without talking to you and blocking up a already busy frequency, in this case what would be acceptable from your point of view. You must ask, even for a small deviation. Horizontal separation is predicated on you staying on track. Also for SID and STAR would you prefer a specific heading or etc deviate up to 5 nm right/ left of trek. Personally I prefer the last which give me more freedom and not blocking the frequency with numerous requested heading requests. Either is acceptable.
4. When in holding we always seems to get 2/3 the holding and the radar vectored to the waypoint. How accurate are your system with arrival times, because we could adjust the speed in the holding within the ICAO limits. To meet our airport Arrival Acceptance Rate (AAR) the Terminal controllers have to accurately (+- 1min deviation) meet the AMAN OCTs. Again, the formula, Interventions = Consequences / Trust applies. HKATCA sees benefit for everyone if holding, OCTs and FMS are the standardised methods of managing arrival delay and is trying hard to convince controllers at a professional level. However, we do see it as a Trust issue.
This was just a few questions from me which I hope you could explain.
Again thanks for this opportunity for us to communicate with you guys.
I have a few questions for you.
1.Quits(sic) often we seem to be radar vectored on both arrival and departure along the STAR or SID +\- less than 1 mile. Are your aircraft separation less when radar vectored compare to on SID/ STAR or what is the reason. Separation in both cases is a standard 3nms. Wouldn't it be easier to use speed and stay on the SID/STAR? It would appear so but we’re learning that it is strongly influenced by individual interpretation. There is a proverb in ATC that states a controller’s interventions per sector, is proportional to that controller’s trust in the system and the consequences of any breakdown (system, here, refers to equipment, the airspace structures and procedures, and ability of aircrew to accurately comply). As a formula: Interventions = Consequences / Trust, you can deduce that as a sector becomes more congested, the risk of Consequences from non-compliance will increase and, assuming Trust remains constant, then the number of ATC Interventions will increase. If Trust decreases, then Interventions soars.
2. On approach we tend to get " speed (ect 210) or greater. Would you normally want us to keep high speed or slowdown towards this speed? Rather than giving you a specific (fast) speed, the controller is affording you three options: 1) keep your present speed, 2) come back to the minimum stated or 3) anything in between. By giving this clearance, the controller doesn’t foresee any consequences from either action. Please note: we are using this clearance because so many operators now, don’t like flying fast inside APP/FAD airspace. The standard ATC speeds are: 280kts in descent, 250kts at 10000’, 210kts on downwind, 180kts on base and 160kts to final, thus when we use “***kts or greater” we’re referring to those standard speeds and want you to go as fast as your company allows.
3. Now the season with weather is upon us, and we need weather deviation. Some time we just need less than 1 mile to get around a TCU. Can we " just " get around it without talking to you and blocking up a already busy frequency, in this case what would be acceptable from your point of view. You must ask, even for a small deviation. Horizontal separation is predicated on you staying on track. Also for SID and STAR would you prefer a specific heading or etc deviate up to 5 nm right/ left of trek. Personally I prefer the last which give me more freedom and not blocking the frequency with numerous requested heading requests. Either is acceptable.
4. When in holding we always seems to get 2/3 the holding and the radar vectored to the waypoint. How accurate are your system with arrival times, because we could adjust the speed in the holding within the ICAO limits. To meet our airport Arrival Acceptance Rate (AAR) the Terminal controllers have to accurately (+- 1min deviation) meet the AMAN OCTs. Again, the formula, Interventions = Consequences / Trust applies. HKATCA sees benefit for everyone if holding, OCTs and FMS are the standardised methods of managing arrival delay and is trying hard to convince controllers at a professional level. However, we do see it as a Trust issue.
This was just a few questions from me which I hope you could explain.
Again thanks for this opportunity for us to communicate with you guys.
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Information/zone
I fly locally and think we get amazing support from ATC who have to deal with Macau traffic, GFS, and other professional local traffic while being extremely accommodating to student pilots who sometimes require three attempts to read back their QNH. My question is how do you roster staff between CLK commercial traffic and local GA? Thanks for the help!
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AMAN Time
Agree with UNIFO. The AMAN time +/- 1 min is ref only.
Even with this +/- 1 min the approach controller still need to work out the spacing on to final, be it vectoring or speed control.
Not until the FMS can make accuracy in terms of secs we can make good use of it to ease vectoring.
Even with this +/- 1 min the approach controller still need to work out the spacing on to final, be it vectoring or speed control.
Not until the FMS can make accuracy in terms of secs we can make good use of it to ease vectoring.
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Bigjames
I fly locally and think we get amazing support from ATC who have to deal with Macau traffic, GFS, and other professional local traffic while being extremely accommodating to student pilots who sometimes require three attempts to read back their QNH. My question is how do you roster staff between CLK commercial traffic and local GA? Thanks for the help!
Once an ATCO is rated in the TWR, they need to work all positions. Both runways (Air Movements Control -AMC) two GMC's, Clearance Delivery and a combination CO-ORD - Zone and Flight Information position. The latter can be very busy or very quiet. As a CO-ORD you support the running of AMC and GMC and conduct most of the effort during runway changes. If there is a considerable volume of traffic it can make the position a bit willing. All controllers on shift get cycled through all positions.
Not all Clearance Delivery operators are ATCOs. Aircrew tend to get impatient on this frequency. What is not necessarily evident is that this position has no jurisdiction over airspace. They are purely an intermediary. In most cases, if you call ready, they need to co-ordinate. Simply because there is no radio chatter doesn't mean they are idle. Also, the overriding metering tool is how quickly we can launch traffic from the runway. Average is 90 seconds to two minutes. So stepping on each other on this frequency is quite senseless. In many ways asking for delays is in the same category. Flow control can be imposed at any time. On an average day it is altered 30-40 times. This is the reality of HK departures.
Once an ATCO is rated in the TWR, they need to work all positions. Both runways (Air Movements Control -AMC) two GMC's, Clearance Delivery and a combination CO-ORD - Zone and Flight Information position. The latter can be very busy or very quiet. As a CO-ORD you support the running of AMC and GMC and conduct most of the effort during runway changes. If there is a considerable volume of traffic it can make the position a bit willing. All controllers on shift get cycled through all positions.
Not all Clearance Delivery operators are ATCOs. Aircrew tend to get impatient on this frequency. What is not necessarily evident is that this position has no jurisdiction over airspace. They are purely an intermediary. In most cases, if you call ready, they need to co-ordinate. Simply because there is no radio chatter doesn't mean they are idle. Also, the overriding metering tool is how quickly we can launch traffic from the runway. Average is 90 seconds to two minutes. So stepping on each other on this frequency is quite senseless. In many ways asking for delays is in the same category. Flow control can be imposed at any time. On an average day it is altered 30-40 times. This is the reality of HK departures.
Last edited by psychohk; 20th Apr 2014 at 11:04.