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UK Traffic Service - almost completely worthless?

I had an “interesting” flight today – Shoreham EGKA to Cranfield EGTC, via MID WOD WCO

On the way up I went at 2400ft all the way, about 10am.

I got a Traffic service from Farnborough South, initially.

There was a lot of stuff on TCAS, as would be expected on a nice Sunday preceeded by months of bad wx. Most of it one never gets visual with, which is also normal…

About halfway between WOD and WCO, looking around for traffic, I saw a plane coming head-on, 12 o’clock. When he was about 200m away, I got a TCAS warning, and it was him allright, same level etc. My guess is that his transponder was weak, because normally one sees traffic on TCAS from several miles away. He saw me because turned a bit to his right and I turned a bit to the right also.

I now fly with the landing and taxi lights on all the time (in Class G, anyway) because they are LED lamps which are not only hugely powerful but also should last a very long time.

Farnborough reported no traffic, even though the frequency was quiet (the controller may have been on another frequency, or on a phone call, of course).

The aircraft was something “long”, like a Saratoga. I was slightly above, maybe 20m, so could not see his landing gear, or lack of. One of the colours was blue and it looked like a custom paint job. It may have been a PA46 although they have long straight wings and it wasn’t like that.

Anyway none of the above is abnormal. A Traffic service comes with a zero assured service level. The controller doesn’t have to report any contacts.

But this is the fun bit: About 1/2 minute after this I called up Farnborough and told them I had a fairly close airprox, and described it. I told him I had him on TCAS and he was definitely Mode C, and possibly S. The controller said he had absolutely nothing on radar on that track, apart from me. But he immediately downgraded the service to “Traffic service with limited radar coverage” or words to that effect, which I thought was really odd. Why would he do that? Did my report throw doubt on his radar? Well obviously his radar was duff, because this was a big metal plane, at 2400ft. No way could you not have at least the primary target. The other explanation is that he missed the traffic (wasn’t looking at the radar) but could not say so on the radio (on the tape).

On the way back, I started off at 2400ft but had so many contacts on TCAS, around my level, and the airspace above wasn’t an issue. I had Traffic service from Farnboorugh North so wasn’t supposed to climb without talking to ATC, but the radio was busy and I wasn’t going to just hang around in the face of known odds, so I started a climb to 3400ft (which would be just under the next bit of Class A) and called them up ASAP saying “climbing 3400ft due to multiple TCAS contacts at my level”. There was bit of silence and then they downgraded the service to a Basic service. Why would they downgrade when I was going higher up, where the radar coverage is even better?

Is this ATC behaviour (a formal abandonment of a Traffic service, when a pilot reports traffic which the controller should have reported) the result of an ATC rule that if a pilot reports a TCAS contact but the controller either didn’t see it on his radar, or didn’t pass it on for whatever reason (e.g. workload, or was distracted) they are required to formally terminate a Traffic service?

I stayed at 3400ft all the way back, doing a bit of a detour to the west, and this is always much more sensible because there was nobody up there at all. The were maybe 50 contacts along that route on TCAS and all at/below 2400ft and nobody above 3000ft – a common scenario for UK GA. Obviously the stuff on TCAS is only those who have Mode C (there were some Mode A targets too but not many) and non-TXP targets are invisible, but it is what one sees all the time in the UK. Very few people of any kind fly above 3000ft.

Administrator
Shoreham EGKA, United Kingdom

Hard to comment on the quality of their radar, and maybe there is someone here who know a bit more about where these feeds come from. I have Farnborough a lot, and tend to find the following:

- Will get reduced traffic service due to radar performance if scud running at around 1500 QNH
- Will get reduced traffic service due to controller workload, and this can be upgraded or downgraded accordingly, though sometimes there is a statement of ‘possible late warning of traffic’
- Will get only basic service when it is a) either busy (today would have been a typical case) b) when one controller is covering say North and West zones.

I have had things come up on my now seemingly defunct ZAON XRX, or things I have seen that have not been reported, when I was on a traffic service. Of course I have also been warned about things I haven’t myself seen.

So useful service, yes. Totally reliable, no. Which is a bit concerning if you take a traffic service to be a full traffic service (any reason why you shouldn’t be able to unless any of the above caveats have been mentioned by the controller?), or worse you are actually in IMC without any TCAS. To be honest I am used it in my life OCAS.

For the extra 5 minutes why not go GWC CPT WCO and stay at 4000 feet all the way? I went to Shoreham from Glos today and considered cutting the corner via MID, but decided to use my normal GWC routing and stay high, 2300 ft in murk is not my kind of fun.

I voluntarily downgraded today when another aircraft with a cadet on board was declined a traffic service due controller workload. Apparently a traffic service is now required with a cadet, presumably since the collision a couple of years ago. TBH at 4000 feet I was above the inversion and in pretty good vis. There was a lot of traffic today, and some of it got quite close, but most of it was called by ATC, and it was well below.

Seems odd to be dropping you like that, but maybe they thought that TCAS would be enough and to divert their resources to the more needy?

EGBJ / Gloucestershire

The altitude is not the issue here. One can actually fly EGKA-EGTC at 5400ft, and another 10-15 mins. I have done that a few times, to stay above cloud.

The issue is why drop a pilot out of “traffic service” as soon as he indicates that he sees stuff which they can’t (or say they can’t) see?

I would have thought that any formal recognition that TCAS is of any use for any purpose whatsoever would be totally against all principles of GA and therefore against all principles of any ATC service to GA.

For example if you are given traffic details, and you can’t see it, but can see what looks a highly likely candidate (you can never be sure it is the same traffic of course) on TCAS, you are not supposed to say you can see it on TCAS. The only options you have are “visual” or “roger”, with the latter meaning you can’t see it. One sometimes hears commercial traffic (bizjets) in Class G saying “have him on TCAS” but that is not standard terminology.

Administrator
Shoreham EGKA, United Kingdom

Actually you’re now supposed to say “Traffic in sight” or “Traffic not in sight”, which seems to break the rule that things with opposite meanings shouldn’t be given similar radio phraseology.
TCAS is very valuable.
Today was incredibly busy, and getting out of controlled airspace at BIG on my way to Fairoaks, controllers were very helpful in helping stir me away from traffic clusters. I’ve never seen so many echoes on TCAS. My son counted 10 contacts within 6nm at one point!
Doesn’t really explain this sudden downgrade, which does feel like ar£e covering – having said that you did rub their nose in it a bit :-)

EGTF, LFTF

Deal with it?

My novice experience suggests ‘traffic service’ is rarely provided with any reliabiity in the UK – they drop you asap by calling ‘limited service’ or ‘basic service’. I suspect the only time you have reliable traffic service is when you are radar controlled in ATC or file a flight plan – i can live with that, the service does not exceed my expectations.

When I fly IMC I know I’m 9/10, totally, on my own and expect and accept contact, that’s why we fly ga, enjoy, frankw

Last Edited by frankw at 09 Mar 22:14

My novice experience suggests ‘traffic service’ is rarely provided with any reliabiity in the UK – they drop you asap by calling ‘limited service’ or ‘basic service’.

Correct.

I suspect the only time you have reliable traffic service is when you are radar controlled in ATC or file a flight plan

Actually, no…

In CAS, i.e. Class A-E, ATC are supposed to separate IFR-on-IFR. If you are getting a “radar control service” you could be VFR, and AFAIK there is no separation in Class D between VFR and IFR (not for the benefit of the VFR traffic, I mean). A flight plan is irrelevant.

In Class G, no separation is provided between any traffic.

But they can’t separate what they can’t see. They only thing working in your favour, when in CAS, is that anybody “unknown” in there is busting CAS, which people aren’t supposed to be doing, so it is a reasonable assumption that not as many will be doing it But it is still a numbers game. Thus far, in the UK, a GA aircraft has not hit an airliner, so the “numbers game” has worked out OK.

However none of this is the Q I was asking.

Administrator
Shoreham EGKA, United Kingdom

Peter thanks for clarification, I have always perceived a greater duty of care when I fly a flight plan… maybe I’ve been deluded and blissfully ignorant… frankw

I have found when it is very busy that a traffic service becomes so busy it can almost be useless. A couple of weeks ago from Brize I had non stop contacts being reported and that was with a reduced traffic service due reception to the north west. As soon as I said copied traffic (or have him on TCAS) he would start rattling off more multiple targets, no height information etc.

I still always take it when I can. Never had to report traffic they didn’t call so no idea what happens if you do. Seems very odd, did you file the airprox? There cannot be a rule that a traffic service is downgraded if you see something they don’t.

Last Edited by JasonC at 09 Mar 22:35
EGTK Oxford

I would think that filing an airprox today would be like reporting getting one’s pocket picked at Barcelona.

There cannot be a rule that a traffic service is downgraded if you see something they don’t.

I agree – it would be amazingly cynical. But to get it twice on the same day?

Last Edited by Peter at 09 Mar 22:40
Administrator
Shoreham EGKA, United Kingdom
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