Heathrow Inbounds descending over the top of London City outbounds

[Skipness One Echo]

BBC News - Jet and Turkish Airlines 777 in 'near-miss' over London (http://www.bbc.co.uk/news/uk-england-london-11237496)

Isn't this becoming worryingly common? Now I happily watched a Citation zoom beneath my LHR inbound in exactly the same place last week but I expected he'd be at least 1000 ft below as I am familiar with the area.

However didn't Air Canada have an issue in exactly the same place descending this time into a City outbound recently?

I used to live near LCY and whilst having seen aircraft perform this departure / arrival dance many times, it seems to me that good fortune has played a part in avoiding a major incident. I'm hardly a tabloid sensationalist but this surely isn't the safest way to seperate traffic with both flows in a crucial and often distracted phase of flight.

What changes are being made to stop this happening for real next time?

http://www.pprune.org/tech-log/288199-near-miss-over-east-london.html

[HEATHROW DIRECTOR]

I worked that airspace for many years and the only incident I encountered was caused by TCAS!. How about all the outbounds from airports all over the UK which climb up under inbounds and overflying traffic with 1000 ft separation? It happens maybe hundreds of times each day. The procedures are perfectly safe; it just depends on pilots and controllers getting them right. The investigation will sort out any shortcomings.

[Roffa]

Isn't this becoming worryingly common? Now I happily watched a Citation zoom beneath my LHR inbound in exactly the same place last week but I expected he'd be at least 1000 ft below as I am familiar with the area.

You've got me scratching my head there, all I can think of is given the procedure put in place following this incident, it just goes to show how difficult it is for observers on the sidelines to accurately judge distance.

[Navpi]

Regardless of the superb professionalism of ATC and 99.9% of pilots the airspace around London is too busy , it is an accident waiting to happen !

There is simply too much traffic ! It should be capped and now !

Whilst TCAS "may" have helped, as Heathrow Director points out it is not failsafe, and he can quote an example where it could actually contribute to an accident !

Adding aircraft like the A380 is great but all the airlines do is maintain frequency !

By way of example BA, AA etc now operate a service almost every 30 minutes to New York , by any reasonable measure surely some of this passenger traffic must originate North Of Birmingham so why not use Manchester ? Three terminals, two runways , it is crazy !

Adding runways in the South east is also no answer, if the airspace above cannot take the extra traffic!

I am NOT part of the green lobby, far from it, but there are vested interests at work here, you cannot base all increases in traffic purely on commercial factors

based purely on critical mass it now makes more sense to ram more and more traffic into the South east, the politicians think jobs etc and follow the lead.....

....but if there is a major mid air over London they will all be scarpering for the exits.

[HEATHROW DIRECTOR]

Navpi. Unfortunately your profile reveals little about you. Would you kindly state your professional qualifications for such statements? Thanks.

[Skipness One Echo]

I was relaxed about the Citation flying under my flght, ( I was a passenger I hasten to add ) as I know LCY departures are restricted to 3000 ft in the first instance and LHR arrivals aren't supposed to be below 4000 ft.

I have seen this maneuvour many times as I was local to the area, my concern is that this is the second reported time in recent years that a large airliner has been involved in a loss of seperation over a densely populated part of London.

It ought to be possible to route Heathrow arrivals far enough East or West of LCY departures but maximising the use of the airspace means that some of them are descending right on top of LCY departures climbing towards them. As a layman it's far from ideal IMHO, if the professional says it's safe, I'm just asking why given the Air Canada incident, it seems to have happened again in the sane place.

Not a journo, just an ex local.

[slip and turn]

As HD and Roffa know, I am also a local to the area in question.

I suppose it could be argued that it is the corporate traffic out of City which is most likely to bust a level if any does. I guess the pilots of such, especially if not City regulars, are more likely to fail to double brief themselves of this particular risk than to forget to check their performance figures for take off. And despite them correctly responding to clearances day in day out, the workload here and keeping up with the aircraft perhaps lends itself to a busted level here more than at other airfields.

As we all know, there on some days and times exists a continuous barrage of opposite heading other traffic, many of the pilots of which I imagine are in practice oblivious to the popularly denied risk of fast lower traffic busting levels up into their Heathrow approach, not so much trusting to TCAS perhaps as trusting that the ANSP has maintained the airspace in failsafe fashion. That they might be oblivious and also at a stage in their approach where they have been progressively turned and descended in the same area to within 1000 feet of opposite fast traffic and furthermore that they will often be largely distracted with a need to descend further and establishing on a neighbouring localiser within the next 60 seconds or so, clearly tempts fate?

I honestly don't know why so many of you in this forum have been so touchy about defending this LCY-LHR overlap over the years. I don't think you could point to anything else quite like it in UK airspace at least? It is no coincidence that at least two of these incidents have happened in exactly the same tiny piece of sky, now is it?

Goodness knows I was criticised enough as a mere mortal over daring to question you guys over it last time it made PPRUNe.

As a matter of general interest, Roffa, what procedure was put into place following the latest incident, please? Is it a delayed clearance down to 4000 for these particular LHR approaches perhaps? I sit here looking north into a view of the exact piece of sky as I type. I think of the last half dozen departures from LCY turning north, three were corporate jets, and I am guessing that in the same time there have been maybe a dozen and a half Heathrow arrivals heading south over Hackney, all of which I am guessing are generally not much below 5000 or 6000, without resorting to checking on a screen somewhere whereas a couple of months ago a good number of them would already be down to 4000 by Canary Wharf and immediately descending further..

It is a great view ... and better by miles on your kit ... of that I have no doubt.

[twentypoint4]

I believe there is a procedure now called "The City Box". The "Box" is a chunk of airspace covering the area where the city departures perform the intial right hand turn eastwards while climbing to 3000'. Heathrow Directors cannot descend their inbounds below 5000' (thus leaving a 1000' buffer) if the aircraft will overfly this area i.e. those on a right base for 27L/R.

As far as i know the City box is only active when City is busy with departures and when it is active Heathrow directors bring up the box on the video map.

[HEATHROW DIRECTOR]

Slip and turn... And your aviation background is, please? It would help the professionals on here if contributors would indicate their background a little. Then we know whether to enter a serious discussion or not. For the record, I'm Brendan McCartney, retired Heathrow (and other places) ATCO with 31 years experience working in the LTMA. I know some people prefer to remain anonymous but some indication of professional aviation involvement would be useful. Tnx.

No matter what procedures are introduced, someone is going to make an error one day.. We are all human, after all. During my time at Heathrow I saw many, many new procedures and revisions to existing ones introduced to enhance safety. I know that the ATC procedures have recently been revised to offer further protection to traffic landing at Heathrow and departing LCY but you cannot legislate for every eventuality. In the end, it's down to humans to follow the instructions...

[slip and turn]

A box? Interesting concept. Lending credence to such a thing might almost have been taken as heresy once upon a time, I bet :p

Seriously, it's good to know that the ANSP can move quickly when it feels the need.

HD, you 'll have to forgive me, don't worry about too much about my blank profile, just pitch your response at your own level and I'll be happy to pick the bones out of it as best I can. :ok:

I very much agree with your summation - in fact I used exactly the same two angles for comparison in the first draft of my last post (comparing legislation via airspace design versus the human factors affecting the pilots in this set of airspace circumstances) but I lost it in the verify login process, and hastily redrafted it. Its good I think that this bit of airspace has perhaps now been "over-engineered" a little in order to compensate.

[HEATHROW DIRECTOR]

Just imagine.... if in every TMA and airway over Europe, when climbing and descending aircraft were likely to get within 1000 ft, they built in an extra 1000 ft.... That would be like saying the standard vertical separation will now be 2000 ft.. And how about the cases when two aircraft get less than the required distance apart horizoantally? Let's make 5nm become 10nm and 3nm become 6nm.. Really, that's what it comes down to - total nonsense!!

[Del Prado]

Hi slip and turn, I'd like to echo HD and ask again what your background/experience is. I have asked you this before without an answer and, if you'll forgive me for saying so, you make very authoritative sounding posts on ATC issues yet you seem to lack a lot of insider knowledge.

It may help followers of this thread if they knew your experience.

Sorry, hope this doesn't sound rude.

[slip and turn]

I agree HD, if they did that everywhere then Emirates would have to make the letters even bigger under their fuselage ... their 380 went over here at 5800 or so this evening and for the first time I couldn't read it :p

I am sorry Del Prado, I prefer to remain anonymous and it has never been my intention to appear as someone with particular knowledge other than what I have seen with my imperfect eyes in this bit of airspace over many years. My aviation knowledge is elementary.

[ZOOKER]

slip,
You say "A box? Interesting concept."
Boxes are more common than you think.
I believe there is a box near Manchester for gliding activity and another box was in existence in the Honiley area several years ago.

[Will_McKenzie]

Heathrow Director, just asking your opinion on one thing...
According to the report the EGLC tower controller issued SID (DOV 4T) and also said "maintain altitude 3A" which the Citation pilot read back "DOV 4T maintain 4A" which the controller missed.
Not putting blame on anybody I hasten to add, I was just wondering why the level restriction was even mentioned as the restriction is on the charts? I appreciate not all charts have them, I have had a few Air France pilots ask about what the SID altitude is but never had to issue it otherwise.
Cheers

[slip and turn]

slip,
You say "A box? Interesting concept."
Boxes are more common than you thinkYes I long ago settled for "boxes" for most of what I thought was a useful 3D rendition in my mind of the relationships between TMAs and other Controlled airspaces.

I guess I was trying to appear a little ironic because I once dared to refer to this evidently troublesome bit of sky as a "cube" in that three and a half year old thread linked to by the OP :oh:

[twentypoint4]

"I was just wondering why the level restriction was even mentioned as the restriction is on the charts?"

I know you asked HD the question, but I thought I'd offer my opinion.

As far as I'm aware the charts (AIP) only show the profile of the stepped climb i.e. climb to 3000', level off for a bit, then further up to 4000' once round the corner. These charts do not hilight the fact that the climb should be STOPPED at 3000'. Therefore the level restriction "mentioned" by the tower controller is an instruction overiding the SIDs' climb profile i.e. climb to 3000' and only subsequently higher once cleared by ATC.

[HEATHROW DIRECTOR]

I cannot offer a definitive answer but I was told that the reason the tower issues the SID altitude is to prevent the kind of incidents which are being discussed here!

[Red Four]

AIC on revised SIDs nicely tied up to coincide with the release of the AAIB report:
http://www.nats-uk.ead-it.com/aip/current/sup/EG_SUP_2010_34_en.pdf

[Talkdownman]

the EGLC tower controller issued SID (DOV 4T) and also said "maintain altitude 3A" .....I was just wondering why the level restriction was even mentioned as the restriction is on the charts?
The ATC "maintain altitude 3A" NEGATES THE STEP CLIMB. It is a revised clearance. It means MAINTAIN 3A FULL STOP.This is where some pilots have been going wrong having stepped to 4A after having being instructed to maintain 3A. (Not very convenient against a Lambourne 180 at 4A...:rolleyes: a frightening experience to hear that sudden "leaving three" report). EGLC Tower issues the SID altitude restriction on behalf of Thames Radar which is responsible for the release. Some Thames Radar ATCOs have, certainly in the past, chosen to impose the 3A stop because they found the interaction of LYD and DVR SIDs and the STARs to be DANGEROUS.

[Talkdownman]

AIC on revised SIDs nicely tied up to coincide with the release of the AAIB report:
http://www.nats-uk.ead-it.com/aip/cu...2010_34_en.pdf
At last. Years overdue. No, decades, even.
Why is it that nats ignores the concerns of ATCOs on its shop-floor only for its hand to be ultimately forced by the AAIB following investigation of a serious incident. nats has been here before...

[250 kts]

It would however make infinite sense not to have the mention of the number 4 in the SID at all. Maybe a DVR 3T would be more approriate and then reiterate 3A in the clearance. DVR 4T and maintain 3A is potentially asking for trouble.

[Talkdownman]

How about a 'DVR September Tango' SID....

[slip and turn]

From the AAIB report:NATS reported that, since January 2004, there have been 21 occasions when aircraft departing London City Airport have climbed above the step altitude of 3,000 ft published in the SID. A third of the incidents led to a loss of ATC separation. Evidence from London Stansted Airport showed that removing the step-climb element of the CPT/BUZ SIDs led to a reduction in the number of aircraft that climbed through the first cleared altitude after takeoff. There were 12 ‘level busts’ reported on the SIDs in the 24 months before the end of 2005 when the step-climb was removed. There were 5 level busts in the following three years and seven months.That's far more history than I had imagined. I take back my somewhat tongue-in-cheek comment about the ANSP moving quickly when it feels the need. Clearly the ANSP felt they knew best at the end of 2005 and didn't feel much disposed to heed a further need until prodded sharply by the regulator.

[zkdli]

If only the regulator had prodded hard...
Those of us who have intimate knowledge of the London City SIDs and the efforts that that have gone in to trying to make them safer over the years would have appreciated little more support from the regulator over this one.

For those of you speculating about the three thousand foot stop, it was instituted several years ago (i think after a series of level busts in 2005) to reduce the risk of continuing level busts in the area. Until 2009 it was considered to have been a reasonable solution.
To the people who think that it is only business aviation that causes the problem think again - FK50s might only climb at 1500fpm but they also used to regularly bust the 3,000ft step. The other issue was the level busts by inbounds, that is why there are so many new procedures for the two routes - ask a BA pilot what he thinks about the "box":hmm:

dive in to bunker to await the incoming!

[Mister Geezer]

The weakest link is not the airspace infrastructure nor the ATS provider but rather the crews. There is a massive spectrum of training standards, abilities of crew members and quality of operational control from commercial operators from all over the world. To say that the London TMA is a multi-cultural environment is perhaps a slight understatement!

Then you have the corporate aviation industry which in some states has little in the way of any tangible oversight or regulation whatsoever.

With the THY B773 incident, I personally thought it was very telling that the commander was in fact a Line Training Captain and he used non standard TCAS R/T and did not follow the RA when he first heard it. Now if that is from an established flag carrier.... well need I say more?

The sad reality is that the difference between standards on the flight deck in the UK and Europe is in some cases a world away from what you can and indeed will see in some other states further afield. You can have a multitude of ATC procedures, initiatives and ideas, yet you still have to rely on the guy in the flight deck doing his job properly.

[slip and turn]

The weakest link is not the airspace infrastructure nor the ATS provider but rather the crews.I heard once that the largest department at the ATS provider is 'Human Factors'. Why? Because the risks associated with inviting the lowest common denominator of your weakest link into their world have to be managed and minimised or in some troublesome scenarios zero-ed out by design (by the ATS provider).

[DFC]

Just imagine.... if in every TMA and airway over Europe, when climbing and descending aircraft were likely to get within 1000 ft, they built in an extra 1000 ft.... That would be like saying the standard vertical separation will now be 2000 ft..


Ah but how often do we experience a level off that is required to be made before the completion of the noise abatement procedure????

On the noise abatement we do not reduce the rate of climb to the ideal of 500 - 1000 ft per min with 1000ft to go for obvious reasons?

Therefore it should be obvious that if one is going to cross an aircraft 1000ft above an aircraft on a noise abatement departure, the rate of climb of the lower might be a bit on the high side for a simple 1000ft tcas (and STCA) free pass!

The "Maintain 3000ft" in city clearances is the most misunderstood example that I have come across. 50% of people I have operated with have said " as per the chart" and without being told otherwise would have climbed at the appropriate point to 4000ft. That is not what ATC expected.

I think that it is amazing that so few problems have occurred!!

Based on what was going on in terms of non-standard clearance procedures, early level-offs, traffic descending on top it is pure luck that there were not far more problems.

As for "Cleared DVR xxx Maintain 3000ft". This is not taking a flight off the SID. It is simply repeating what is part of the SID.

I believe that if the SID is to be cancelled then a full clearance is to be provided i.e. something like "climb straight ahead to 1.5dme and then turn right to establish outbound on the LON xxx radial climb to 3000ft.

What has probably saved the day on many occasions is that the airport operator requires that all crews receive initial and regular refresher training before being authorised to operate into the airport and while a lot of time is spent on the arrival aspects, there is some time devoted to departures and the "local practice of wanting flights to maintain 3000ft "full stop" on the SID.

[Gulfstreamaviator]

Luton used to be the nightmare departure due to the STEP climb, and IMHO a very unclear ATC clearance.

Is it still as bad, or has City taken the lead.

Glf

[DFC]

Luton has the step climb and quite a few turns and various legs that can all happen a bit quickly for those not familiar and who let the speed rush away a bit but aircraft are cleared on the SID and are required to follow the SID vertical profile with no local non-standard revisions.

The problem is that

day 1 - Luton - stepped climb - follow the steps or there will be big trouble

day 2 - City - stepped climb - don't follow the steps because if you do there will be trouble.

day 3 - Northolt - stepped climb - follow the steps or there will be trouble.

Now which is the odd one out?

[error_401]

It's on the ATIS of LCY anyways not to climb above 3000 feet after departure.

On the departure I think it's sensible of the crews to level off at 3000 unless cleared otherwise. Normally we reach 3000 even before intercepting the LHR radial eastwards.

Watching the TCAS and reducing rate of climb when reaching 3000 helps as well. I normally keep it at or below 1000 ft/min in the terminal area.

When departing LCY I use V/S 1'000 ft/min for the step climbs unless in the DVR area when cleared to a higher level. This reduces the risk of TCAS triggers with opposite descending traffic. Inbound or outbound this greatly helps. The lower rate also gives more time to monitor.

[Talkdownman]

On the departure I think it's sensible of the crews to level off at 3000 unless cleared otherwise.
Sensible? It is a Requirement (http://www.nats-uk.ead-it.com/aip/current/sup/EG_SUP_2010_34_en.pdf)...

[Over+Out]

Did I read that the SID's are changing to ''maintain 3000 ft''
Can anyone confirm this please?

[Talkdownman]

Over+Out, do you read (http://www.nats-uk.ead-it.com/aip/current/sup/EG_SUP_2010_34_en.pdf)? Over....

[Over+Out]

Thanks for taking the time to find the answer