Radar Headings vs. Flight Planned Route

[DTY/LKS]

Denti

You mention that apart from in the TMA in Germany then headings are rarely used;
In your examples about flying from EGSS to EGCC, you basically remain in TMA airspace the whole flight. As soon as you leave the London TMA then you will be soon entering the Manchester TMA.

Flying EGSS to EGPF then you will be on headings coming out of TMA due to the complexity of traffic around you, then as you climb up through the Daventry sector then you will be on a heading against fellow London TMA deps and also against high level Manchester TMA inbounds that need to descend through your level, not to mention all the cruising traffic in the low 200 flight levels. Once cruising then you will probably be released from your heading to POL or MARGO. Then the ATCO needs to start thinking about positioning you in relation to other Scottish TMA inbounds, so will set you up on a heading for Scottish ATC, then before you know it you are in the Scottish TMA.

We don't put aircraft on a heading for the fun of it. Our little country has a lot of traffic taking off rom it, landing in it & overflying it. If you are on a heading then 99.9% of the time it will be for separation purposes.

[daisy120]

separation again.

This 3 miles thingy is quite interesting but on the LAM3A arrivals LHR, the headings are mostly within1nm of NAV track. Does that really make a difference baring in mind that once a heading is issued, an Airbus managed descent has to be controlled in HDG/OPEN DESC..not a big deal but more of an irritation since one then has to focus more on the profile. Also. within the London TMA, what are the ATC heading and speed ACTUAL, realistic tollerances for the a/c you're controlling? BTW...still don't buy that QNH and type readback mallarcky at LHR!!!!

[Showa Cho]

So I gather if you use radar headings for aircraft in close proximity in case they deviate, then you must also use 1500ft instead of 1000ft for aircraft that will pass overhead each other in case they bust their level a bit?

[HEATHROW DIRECTOR]

<<still don't buy that QNH and type readback mallarcky at LHR!>>

Why ever not? It surely happens at many other airfields and it's to do with SAFETY. It is obviously essential to have the correct QNH and the aircraft type information is required because airlines frequently switch aircraft types without telling ATC. If you were in an MD-80, or 737 or similar and ended up 2.5 nm behind an A340 or 747-400 you might then understand why it is done.

It matters not what people say on here, UK ATC will continue to function the way it always does. So far as my old brain recalls, there has not been a mid-air collision in UK controlled airspace since 1946, which is something we're jealously proud of.

[1985]

This 3 miles thingy is quite interesting but on the LAM3A arrivals LHR, the headings are mostly within1nm of NAV track. Does that really make a difference

Daisy120, if you are coming from Hong Kong then you will probably be kept on route or slightly north of it because of where you enter the CLN sector (REFSO), if you are on a heading then it will be so that we can either parallel other EGLL traffic against you from the south, descend traffic thats inbound to other places in the LTMA against you or get you through the overflights that are always there. The times of day that the Hong Kong flights arrive is busy with all the other far east arrivals at the same time as well as the early arrivals from less distant places. CLN (the westbound side) is only about 50nm wide at its widest point and narrows like a funnel with all the airways meeting at LAM. So you have to put aircraft on headings to achieve what you have to do, especially if there is a large mix of traffic.

[jackieofalltrades]

So I gather if you use radar headings for aircraft in close proximity in case they deviate, then you must also use 1500ft instead of 1000ft for aircraft that will pass overhead each other in case they bust their level a bit?

Aircraft on their own nav may deviate to avoid weather without first informing the controller, whereas if they're on a radar heading they have to request first before changing. The whole point of radar headings is to ensure separation and safety.
We don't use 1500ft just in case they bust their level a bit, but it's not unusual for controllers to give a 2000ft separation buffer in the instructed level if an aircraft will be rapidly climbing/descending and the two aircraft are likely to pass overhead, especially when there are military fast jets involved.

[Roffa]

Also. within the London TMA, what are the ATC heading and speed ACTUAL, realistic tollerances for the a/c you're controlling?

There are no tolerances, you should fly them as accurately as possible and always remembering that if you're Mode S equipped you are downlinking what you are doing to ATC.

This is important because a small heading deviation may well lose lateral separation and, especially on final approach, not flying the requested speeds may at best result in you being broken off the approach or at worst a wake encounter at low level.

If for any reason you're unable to fly requested speeds/headings don't just surreptitiously try and do your own thing, say something and ATC will accommodate as that's what we're there for.

[gumpfgrumpfl]

so.... just to get this straight at last: in the uk you do not have to ask first to deviate because of wx when own nav? creepy.
I can't check my documents right now, but anyway, it never happened to me that a pilot deviated before asking me if he may. And every pilot I asked stated that he/she had learned from the beginning to ask for a deviation before turning.

@ron83: its 2.5nm 18miles from touchdown here... and I can't remember having the authorities here daring something ICAO didn't cover, so 20nm maybe right (or 20nm from runway end, which would be around 18nm touchdown). anyway, would like to look it up, pity I'm at home

[ferris]

Aircraft on their own nav may deviate to avoid weather without first informing the controller,

BS- absolute BS. UK AIP "track keeping" refers. This has been done to death on this forum before.

[Scuzi]

Originally Posted by ferris

BS- absolute BS. UK AIP "track keeping" refers. This has been done to death on this forum before.

Experience proves otherwise.

[jackieofalltrades]

Quote:
Aircraft on their own nav may deviate to avoid weather without first informing the controller,

I should clarify: the use of the word "may" is in the sense that aircraft might do it, not that they are authorised to.
Pilots should, and normally will, ask first before deviating to avoid weather, but like Scuzi says, experience is that they don't always.

[Showa Cho]

Jackie: I understand that sometimes aircraft will wander, but to preemptively cater for pilot violations is another great example of dumbing things down instead of making aviation smarter.

If a pilot deviates without a clearance to do so NAIL HIM/HER! Why do you plan for preventable errors? Prevent them in the first place.

The message will get through if enough companies/pilots get nice letters from the CAA.

Domo,

Showa Cho.

[jackieofalltrades]

Why do you plan for preventable errors? Prevent them in the first place.

Showa, that is my exact point I was making earlier in this thread. That is why in the UK so many aircraft are placed on radar headings, to prevent the planes wandering and thus ensure separation.

to preemptively cater for pilot violations is another great example of dumbing things down

I will have to disagree here. It's called defensive controlling. And gives rise to much safer skies by identifying potential errors and setting up actions to prevent anything untoward happening before it does.

[dcb2008uk]

Some of the comments made in this thread I think serve to highlight why a greater effort should be made for pilots to visit operational centres in the U.K particularly those in a TMA environment so they can see just why the controlling in this country differs from our colleagues overseas.

I'm sorry that it comes across that some of the things we do are unnecessary, or add excessively to your workload, but its the quality of the training that we recieve in this country, coupled with the complexity of many sectors, which makes much of this work necessary.

[gumpfgrumpfl]

quote: 'but its the quality of the training that we recieve in this country'

so not applying radar vectors when separating with 3nm is unprofessional?

quote:
Quote:
to preemptively cater for pilot violations is another great example of dumbing things down
I will have to disagree here. It's called defensive controlling. And gives rise to much safer skies by identifying potential errors and setting up actions to prevent anything untoward happening before it does.

Personally, I rely on pilots to stay on their route almost as much as to stay on their assigned altitude. Actually, more level busts happened to me than misnavigations. So what you call defensive controlling would in the first place call for 2000ft vertical sep.

I do not cater for pilot violations either. I control my traffic so that normal separation is assured, counting on pilots to do what I tell them. I do have a plan to prevent collisions when violations happen.

What potential errors do you mean? You really sit at your scope and control like any of your targets is likely to deviate or violate at the next possible moment?

[HEATHROW DIRECTOR]

<<I control my traffic so that normal separation is assured, counting on pilots to do what I tell them.>>

Which is precisely what the London controllers do!

[dcb2008uk]

I'm not quite sure how me emphasising why it is that we use so many headings in this country was ever me having a dig at the professionalism of other ATCO's in other countries.

I personally, and I imagine almost every other ATCO valid in the UK would not rely on pilots remaining on their own navigation when using 3nm separation.

The purpose of my reply was purely to highlight to pilots why it is that we use so many headings. Dont spin that round to suggest that I was being arrogant as to the quality of ATCO's in this country compared to others.

[On the beach]

Surely the routes can be designed so that they are all laterally separated with built-in height requirements (I hesitate to use the word "restrictions" because this has negative connotations) and don't need the intervention of controllers. I appreciate that the London TMA is small but surely this is possible in this day and age, I mean we're only talking a mile or two. It would certainly increase the capacity handling ability of controllers if they were not constantly having to control the tracking of all aircraft under their control, which seems to be the case from previous posts.

I haven't worked the London TMA so am happy to be contradicted, but having worked the "Celtic Fringes" after a life of working in ATC overseas I am somewhat astounded at how far behind current control techniques and practices NATS is lagging. I feel that there is an in-bred, blinkered culture of "we're the best and the rest of the world can learn from us". Whereas the reality is that the rest of the world has moved on and NATS seems to have been left behind in an anachronistic bubble. If I mention RNP or PBN in the UK, I am normally met with blank stares, which astounds me.

Surely, the only way to increase en-route capacity is to not have controllers putting all aircraft on their frequency on headings. I mean, this is so labour-intensive and distracting from one of the other primary functions of controlling after safety which is expedition.

The current methods of controlling in the London TMA must have an in-built limit as to how much traffic this method of controlling can handle. How close are you to that limit? What are the plans when that limit is reached? Or do you just sit back and watch all the traffic overfly to Paris/Amsterdam/Frankfurt or re-route to avoid the "weak link" in the chain?

On the beach

[HEATHROW DIRECTOR]

<<Surely the routes can be designed so that they are all laterally separated with built-in height requirements (I hesitate to use the word "restrictions" because this has negative connotations) and don't need the intervention of controllers. I appreciate that the London TMA is small but surely this is possible in this day and age, I mean we're only talking a mile or two.>>

On the beach.. With respect, you do not seem to appreciate the workings of ATC in a TMA. "A mile or two" is a huge amount in busy airspace with inbound, outbound and overflying traffic with enormous speed variations. Radar is there precisely to expedite traffic yet you appear to be advocating a return almost to procedural control.

I know what RNP and PBN mean but flying particular routes with a hgh degree of accuracy does not solve the problem of many aircraft climbing and descending on crossing tracks; some form of control has to be imposed. Some of the earlier postings on this thread from DTY/LKS and others explain the problems very well.

I do very strongly urge you to visit Swanwick when you are next in the UK so that you can appreciate the problems they face. It might assist you with your consultancy work.

[daisy120]

ok la.

DCB and 1985, thanks for the heads up. Definitely, a trip to Swanwick on the cards...is there a laid down protocol for the guys to organise a visit??(letter, e/mail etc). I fully understand that traffic density, especially with 'funnelleing' occurring close in, increases collision threat but surely if, eg LAM3A, all inbounds are mandated to fly the STAR, obey the SLP's etc, headings would be minimised....?
Now then, this QNH business, inclusive with the departure ATIS:if we are underlining QNH readback as a safety issue then why do we not include it with the confirmation of the arrival ATIS? For London, its simply a/c type. Outside UK, its a rarity to read back QNH until one has been cleared in the descent to an altitude; after all, one of the fundamentals, even at the basic stages in R/T education, was to keep the R/T broadcast, short, concise and clear. I do find that at LHR and particularly with London East, there can be so much R/T traffic on freq, that simply getting a word in, incurs quite a delay. By acknowledging, prior to start request, that you are.."callsign, stand, type and atis "X ray", you are confirming that ALL the essentials have been received. Afterall, if this is to recap the absolute safety issue of setting the correct QNH, then prevalent in other matters of safety to the a/c operation would be surface wind gust(to possible a/c limit across the runway and temp with dew point..Eng anti ice procedures etc...so why not read back the whole ATIS verbatim???...anyway, last on this one since I fear its becoming a polemic!!