UK: Basic/Traffic/Procedural/Deconfliction air traffic services. Please, explain.
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UK: Basic/Traffic/Procedural/Deconfliction air traffic services. Please, explain.
Can somebody explain how these services are different to the ICAO's Flight Information Service? What's the point of each separate service?
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ICAO Annex 11 and PANS-ATM require some interpretation and some expansion to be deployed operationally. Unlike ATC service, the content is insufficient, particularly in relation to the provision of FIS using surveillance.
The UK FIS provides this extra content but splits up the different ICAO requirements (those related to IFR/VFR and identified and unidentified flights) into different service levels. The idea is that it makes it more intuitive for pilots but it hasn't done that. In part because the training of pilots in air traffic services is woefully inadequate leaving them to read and learn it for themselves. Many pilots have done that and truly understand what is going on but a large minority don't bother which has safety implications for all other airspace users.
The UK FIS provides this extra content but splits up the different ICAO requirements (those related to IFR/VFR and identified and unidentified flights) into different service levels. The idea is that it makes it more intuitive for pilots but it hasn't done that. In part because the training of pilots in air traffic services is woefully inadequate leaving them to read and learn it for themselves. Many pilots have done that and truly understand what is going on but a large minority don't bother which has safety implications for all other airspace users.
I have long been an advocate of providing FIS using radar as per ICAO Doc 4444 para 8.11 (which contrary to whowhenwhy's opinion is quite clear in my opinion) as I understand they do in France and some other European countries.
When 'workshops' were being held during 2007 to discuss the replacement of FIS/RIS/RAS, I attended one and tried to suggest the UK provide services as per the above but my suggestion fell on deaf ears.
When 'workshops' were being held during 2007 to discuss the replacement of FIS/RIS/RAS, I attended one and tried to suggest the UK provide services as per the above but my suggestion fell on deaf ears.
Don't get me wrong Chevvron, we've been in violent agreement before about the need to adopt ICAO FIS. What I mean is that Annex 11 and PANS - ATM don't give you enough information to tell you how to do it. How to use surveillance to provide FIS alongside ATC service yes. How to use surveillance for FIS alone... no.
The old FIS/RIS/RAS as provided by Farnborough was perfect in my eyes. It's a real shame they had to tinker with it "in the interests of simplicity". Things haven't been the same since.
If you want, I can bore you all by explaining the different systems.
Chevvron I would be interested to know what was there before 1974, the changes and which you felt was the best system as a LARS controller (I think you used to fly and would be interested to know if your preference as an ATCO differs from your preference as a pilot). I would also love to understand how the current buggers' muddle is an improvement on FIS/RIS/RAS, but I doubt anyone can help me there.
When I arrived at Farnborough in '74 and up to the late '70s, the system was:
FIS - Proximity hazard warnings; radar derived information could be used whether the aircraft you were providing service to was identified or not. (No SSR at Farnborough until 1981)
VMC Radar Advisory Service - On identification, the pilot advised you of his flight conditions and any subsequent change; the controller provided information on observed conflicting traffic but no avoiding action unless requested by the pilot or deemed necessary by the controller.
IMC Radar Advisory Service - as above but if the pilot said he was IMC, avoiding action would be passed by the controller followed by information about the conflicting traffic.
Procedural Service - non radar service to participating aircraft only.
Radar Control Service - provided for autonomous crossings of airways and applied before the aircraft entered controlled airspace until the aircraft had exited controlled airspace.
Late '70s (late '76 or '77 I think but I'm not sure) to 1980.
FIS - traffic requesting FIS was not identified and proximity hazards on other traffic were limited to other aircraft working the same ATC unit.
Radar Advisory Service.(RAS) - No requirement for the controller to know flight conditions; avoiding action against observed conflictions passed followed by any other known information about the traffic. This was later modified at the request of aircrew so that if the confliction was noticed with sufficient time, traffic information could be passed first followed by avoiding action thus enabling the pilot, if VMC, to look for the traffic and at his discretion decline avoiding action.
Procedural Service and Radar Control as above.
However, this did not allow sufficient flexibility for aircraft operating in MTAs (Military Training Areas) to carry out their programmed task without being vectored all over the sky so:
1980/'81
Traffic Information Service (TIS) was invented whereby, irrespective of Flight Conditions, the pilot would be passed traffic information but no avoiding action unless he requested an upgrade to RAS. TIS was intially only authorised for ATCRUs (miltary area radar units) and MOD(PE) units such as Boscombe Down, Farnborough and Bedford all 3 of which provided Area Radar services in addition to approach radar services.
1981 - 2009
TIS was re-named Radar Information Service (RIS) and authorised for all radar units providing service in the 'open FIR' now called Class G airspace.
With the widespread provision of SSR to airfield radar unts, it was recognised that FIS traffic could become 'known traffic' more easily so it was permitted to either identify FIS traffic using SSR or issue a 'conspicuity' squawk to such traffic; once identified and workload permitting FIS traffic could be passed 'generic' traffic information but not using the 'clock' code as this would be too similar to providing RIS.
RAS could only be provided to IFR traffic whether operating in IMC or VMC.
2009 -
You should know the rest.
Personally I preferred the 'original' system because it was easier to operate without SSR, the controller knew that if you passed traffic info under 'VMC RAS', the pilot had a good chance of seeing it and taking his own avoiding action and it meant that unlike if you were providing RIS or TS under the later systems, you could pass advisory avoiding action without asking the pilot if he/she would accept an upgrade to RAS/DS.
Bear in mind, I'm thinking back up to 55 years so some of my details and timescales may not be exactly correct.
FIS - Proximity hazard warnings; radar derived information could be used whether the aircraft you were providing service to was identified or not. (No SSR at Farnborough until 1981)
VMC Radar Advisory Service - On identification, the pilot advised you of his flight conditions and any subsequent change; the controller provided information on observed conflicting traffic but no avoiding action unless requested by the pilot or deemed necessary by the controller.
IMC Radar Advisory Service - as above but if the pilot said he was IMC, avoiding action would be passed by the controller followed by information about the conflicting traffic.
Procedural Service - non radar service to participating aircraft only.
Radar Control Service - provided for autonomous crossings of airways and applied before the aircraft entered controlled airspace until the aircraft had exited controlled airspace.
Late '70s (late '76 or '77 I think but I'm not sure) to 1980.
FIS - traffic requesting FIS was not identified and proximity hazards on other traffic were limited to other aircraft working the same ATC unit.
Radar Advisory Service.(RAS) - No requirement for the controller to know flight conditions; avoiding action against observed conflictions passed followed by any other known information about the traffic. This was later modified at the request of aircrew so that if the confliction was noticed with sufficient time, traffic information could be passed first followed by avoiding action thus enabling the pilot, if VMC, to look for the traffic and at his discretion decline avoiding action.
Procedural Service and Radar Control as above.
However, this did not allow sufficient flexibility for aircraft operating in MTAs (Military Training Areas) to carry out their programmed task without being vectored all over the sky so:
1980/'81
Traffic Information Service (TIS) was invented whereby, irrespective of Flight Conditions, the pilot would be passed traffic information but no avoiding action unless he requested an upgrade to RAS. TIS was intially only authorised for ATCRUs (miltary area radar units) and MOD(PE) units such as Boscombe Down, Farnborough and Bedford all 3 of which provided Area Radar services in addition to approach radar services.
1981 - 2009
TIS was re-named Radar Information Service (RIS) and authorised for all radar units providing service in the 'open FIR' now called Class G airspace.
With the widespread provision of SSR to airfield radar unts, it was recognised that FIS traffic could become 'known traffic' more easily so it was permitted to either identify FIS traffic using SSR or issue a 'conspicuity' squawk to such traffic; once identified and workload permitting FIS traffic could be passed 'generic' traffic information but not using the 'clock' code as this would be too similar to providing RIS.
RAS could only be provided to IFR traffic whether operating in IMC or VMC.
2009 -
You should know the rest.
Personally I preferred the 'original' system because it was easier to operate without SSR, the controller knew that if you passed traffic info under 'VMC RAS', the pilot had a good chance of seeing it and taking his own avoiding action and it meant that unlike if you were providing RIS or TS under the later systems, you could pass advisory avoiding action without asking the pilot if he/she would accept an upgrade to RAS/DS.
Bear in mind, I'm thinking back up to 55 years so some of my details and timescales may not be exactly correct.
