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Old 14th Feb 2015, 03:39
  #130 (permalink)  
psychohk
 
Join Date: Mar 2006
Location: Hong Kong
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REPLIES TO RUNWAY OPS

nike: Landing traffic on the South (departure runway) is an airline/industry agreed policy. It is referred to as TRAM (Tactical Runway Allocation Mode). When the TMA gets overloaded, TRAM is likely to be declared. The flow will select up to 6 aircraft in an hour to land on the South runway. This enables the Director to squeeze the sequence. It is not easy to accomplish with a single entry point form base leg, but some controllers can manage with a specific technique. Slowly those that can are educating others.

It does impact the departure flow significantly, but can be minimised if crews comply with instructions. Clearly the rationale is that airborne traffic and the ATC manageability of the airspace takes precedence over the ground traffic.

If there is a busy outbound flow and it's imposed, it backs up the traffic quickly.

777: Whilst I accept your point, GMC has a very complex role already dicing up the outbound traffic to accommodate Mainland and in-trail restrictions. To add another complication to that sequencing will be quite taxing. In the near future, the mid field concourse will open. This will provide another outbound flow of traffic to add to the mix. To add to the complexity, the A380 is not permitted to use the majority of taxiway H. If we are directed to do it we will, but this has not been mentioned previously.

4 driver: I understand your frustration. The facts of the matter are that we are 100% busier than about 10 years ago. Traffic will continue to increase. ATC and Aircrew can't keep saying the same volume of R/T and increase movements. Both parties need to do and say less.

It is not uncommon for crews to request the relaxation of restrictions when there is no chance they will bust whatever is imposed. It simply adds to unnecessary R/T. If controllers permit 'unrestricted' in relaxed traffic, they are setting you and the system up for operations in busy traffic. It is much more efficient, safer and less complicated if you simply comply with your clearance.

Having said that, there is no doubt how phraseology has been introduced without 100% industry input, has created a lot of the angst. Hopefully this will be addressed and clearances dictating how you are to descend will be appended to your instruction. "descend on STAR", "climb on SID", "descend to 2000' visually", for Australian trained crews "not below DME steps". It removes all ambiguity.

Dribbler: Minimum spacing is that we are aiming to provide DEP's with 4 nm in- trail. This is usually provided when the first airborne crosses the upwind end then the next departure is released. It can be compressed to approximately 3/4 of a runway length, using aircraft differential performance say in the case of an A340 following a long haul 300ER. For an A380 following anything, 3/4 is generally acceptable as they are slow to roll and slow to accelerate after airborne. If you're following a business jet 1/2 to 3/4 will be adequate. So if you're in one of the lesser performing categories mentioned, expect an early release. It dramatically reduces the departure queue in minimum time.

crwkuntroll:
I'm sorry, but I'm not sure if you identify yourself as a team player or not. HK ATC works extremely hard at doing the best they can within the very complex limitations and lack of integrated flow control both outbound and inbound. Europe, the UK and all of North America are in another category. They all possess centralised flow and total regulation of traffic including imposing ground stops to immediately limit traffic.

If you were to spend a brief period of time behind any busy controller you'll immediately witness the very complex dealings they are faced with and the vast majority of that complexity is not reflected on the frequency. For you to object to being cleared for an "immediate take-off" with a lander at 7nm demonstrates a basic lack of understanding. If you roll immediately there is the distinct possibility of getting a second departure away. Maybe even a freighter to cross the runway as well prior to the landing. All to minimise delay to others and fuel burn.

No big deal if we lose a slot. Or is it? If TWR can't release the second aircraft because you take it upon yourself to dawdle, the next departure will incur 3 to 4 minutes of delay. However, generally the queue to the holding point in Hong Kong is never ending. So that 4 minute delay accumulates through the entire queue. 10 at the hold and you've generated 40 minutes of delay to aviation with engines running. If the queue is endless all players accumulate the delay.

Just using wake turbulence separation as an example, what would you prefer? The international standard plus 30 seconds? Why not a minute? In fact if a minute is better, why not longer? I trust you can see this is not workable with the custom we have, especially when you commit someone to the runway with landing traffic. There has to be an expectation of compliance with standards.


ATC asks for expedition, why? Always to accommodate other traffic. Yet we are frequently responded to with "I'll see what I can do", "we'd do our best", "we are very heavy", "we're already at a reasonable speed". De-motivate controllers from trying to do their very best to minimise delays and you'll see them escalate drastically. You also must understand that a controller with just 5 years of ATC experience will have seen literally thousands of aircraft movements. It is quite apparent to them what aircraft can and can't do, who is accommodating and who is not. When we request expedition, we NEVER expect a reckless action. Only what you are willing to accept. The only time we want otherwise is if you ask not to be rushed. This is not a problem and you'll be re-sequenced. Pulling this manoeuvre at the holding point lacks airmanship. For controllers, if there is any doubt that a crew may slow, not accelerate, take their time, we'll impose expedition to ensure it occurs. It is poor technique and not proactive to control in such a manner. It is NOT a criticism.

Im curious reference your account of wake turbulence. You mention 90 seconds behind an A380 or 748. Behind an A380 is 2 minutes. For a heavy departing behind a heavy, there is no wake turbulence time standard. We use ICAO standards. Here is something that may assist from a previous post. By your logic, we need to be able to accommodate endless requests for flexibility. There are 130 or more airlines flying into HK and an almost limitless number of corporate jets flying here. I trust you can see the impact on efficiency if we were to permit and an unlimited menu of requests.

Medium following a Heavy - 2 minutes on departure - 5nm in trail when inbound or crossing traffic not 1000' above or below you.
Medium following a Super - 3 minutes - 7nm & 1000' applies
Heavy to heavy - not applicable - 4nm in trail & 1000' applies
Heavy following a Super - 2 minutes - 6nm in trail & 1000' applies

Medium crews remember 2 and 3 minutes (behind a Heavy & a Super) + 5 and 7nm in trail
Heavy crews remember 2 minutes (behind a Super) +4 and 6nm in trail.

Alistar: There is a significant movement towards saying less on frequency. Your phrase while correct is highly undesirable if it is repeated 600 times a day.

If you are in-trail of another aircraft from the same holding point, you will generally be instructed "line up RWY07R". Crews are quite robotic and react with alarm, "ok, roger, behind the departing traffic line up and wait behind RWY 07R". This would imply that you could have lined up in front of the departure. The line up clearance is simply a clearance for you to enter the runway, not intended to separate you from traffic. If however, you are to line up behind a departure from the full length and you are at an intersection, the behind phraseology will be used. The reduction in R/T is enormous and has a much greater chance of not being misunderstood by an non native English speaker.

This is the sequence taught in HK ATC.
1. first aircraft is cleared for take off
2. second is cleared to line up
3. approximately when the first crosses the upwind end, the next is released.
4. next told to line up
5 when the departure is above 2000' and complying with the acceleration expectation, it is switched to DEP. Due to your workload and high threat environment immediately after departure we delay talking and assigning a task. The switch is a low priority item, but crews continually call early and quesiton "do you want me to call departures"?

TWR need to see your data label fill in completely prior to handoff. Quite often the callsign doesn't associate. So all DEPs can see is an SSR return. Quite often garbling with other ground traffic under tow not being filtered. No altitude component. Macau arrivals cross directly overhead and can overlap you target completely. In any of these circumstances we hold you on frequency. So unless you are rapidly approaching 5000', please let us come to you, not vice versa. Remember every time you initiate a call instead of us, you double the air time taken for the exchange. Getting frustrated with getting a call in on frequencies, then think carefully before you make your next request.

Hopefully we can get the switch put on the SID plate at an industry agreed standard of 2000' or slightly higher depending on cockpit workload.

So for a departure RWY 07R, discounting rarely used intersections departures, if you are at K1, J1 or J2, there is a 33% chance you will be the next to depart. Considering it takes roughly 80 seconds for a departure to cross the upwind threshold, I find it difficult to comprehend why it takes so long to get into position and then secondly, add thrust. It is rare that you'll arrive at any of these holding points as number 1. So adequate time to prepare your reaction when you get the call. Similarly 50% of traffic can comply. Why?

I would ask all crews the same question, would you behave this way at Heathrow or JFK? If the answer is no, then why 2 standards of behaviour?

I think many of the issues raised here are lost in translation when you consider HKIA now moves 1100 movements a day with 650 through area flights, with a single initial departure track, single entry point onto final and terrain up to 3300' immediately south and paralleling the arrival and departure tracks and no integrated flow control with adjacent ATC units. If you get frustrated, please don't take it out on the controllers. Surprising as it may seem, we are doing the best with what we are dealt with. Do we make mistakes -absolutely. Don't apply what used to happen here, because it was probably 30 to 50% less busy. Increases in traffic levels in congested and restricted airspace bring an exponential increase in complexity.

Balus man: you raise all very valid points. In particular highlighting the continual interjections for start-up. (see comment above about aircrew initiating calls rather than ATC) However in line with the intent of this forum, please don't be confrontational. There is a great deal of ignorance of the 'others role' and that's what we're trying to address. Thank you for your contribution and speaking up. Sign up for a Fam Flight and get your message across in person. Also consider coming to any ATC/Aircrew briefing.

Last edited by psychohk; 14th Apr 2016 at 05:27.
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