46TH ANNUAL CONFERENCE, Istanbul, Turkey, 16-20 April 2007
WP No. 88
Aerodrome – Review Policy on Provision of ATS at Aerodromes
Presented by TOC
The Danish Air Traffic Controllers Association (DATCA) was experiencing problems defining the appropriate qualification for a particular service provided at aerodromes. Changing the level of service during the day and the incorrect use of phraseology by Aerodrome Flight Information Officers (AFISOs) in Denmark caused confusion to pilots as to the quality of service provided. The Technical and Operations Committee (TOC) was tasked to investigate this matter and to review the policy on provision of ATS at aerodromes. In the opinion of TOC the guidelines and requirements set by ICAO should be sufficient to achieve the appropriate level of ATS at aerodromes. However due to recent developments, influenced by economic reasons, TOC proposes to change IFATCA Policy.
1.1. This paper investigates provision of ATS at aerodromes based on the presentation of the Danish Air Traffic Controllers Association (DATCA) in Kaohsiung 2006. DATCA was seeking to address the problems associated with defining ATC requirements and the use of different services at different times at the same location. DATCA was experiencing frequent problems with defining what the appropriate qualification for a particular service provision should be.
1.2. The desired outcome of DATCA was to establish IFATCA policy that would determine that provision of only one service at an aerodrome was recommended. During the presentation it became clear that several Member Associations (MAs) provide different kinds of ATS (the term ‘Air Traffic Services’ comprises 3 services, namely: air traffic control service; flight information service; and alerting service) at one particular aerodrome. These MAs are satisfied with this situation. Therefore the original working paper was submitted as an information paper.
1.3 The Technical and Operations Committee (TOC) has been tasked to review policy on provision of ATS at aerodromes. This paper has been prepared to report the findings of this review.
2.1. There are three different kinds of services that can be provided at aerodromes. ICAO Air Traffic Service Planning Manual Doc 9426 (Part 1, chapter 2) mentions the following services:
- Flight Information Service;
- Aerodrome Control Service;
- Air Traffic Advisory Service.
ICAO Air Traffic Service Planning Manual Doc 9426 further states that:
“it should be clearly explained to users so that no misunderstandings exist as to the quality of service they can expect”.
2.1.1 Aerodrome Flight Information Service (AFIS) is described in ICAO Circ.211-AN/128 as follows:
“A service provided for the purpose of giving information useful for the safe and efficient conduct of IFR operations at uncontrolled aerodromes. The AFIS operator is responsible for:
a) relaying ATC clearances.
b) issuing information on behalf of the aerodrome operator, to aircraft on the manoeuvring area in order to prevent collisions between aircraft and vehicles/obstacles on the manoeuvring area, or between aircraft moving on the apron.
c) providing aircraft with essential information about the state of aerodrome and its facilities.
d) meteorological and other information.
e) providing alerting services.”
2.1.2 ICAO Air Traffic Service Planning Manual Doc 9426 defines Aerodrome Control Service as:
“A service provided for the purpose of:
a) preventing collisions:
1) between aircraft, and
2) on the manoeuvring area between aircraft and obstructions
b) expediting and maintaining an orderly flow of air traffic”
And Air Traffic Advisory service is defined as:
“A service provided within advisory airspace to ensure separation, in so far as practical, between aircraft which are operating on IFR flight plans.”
2.2 Not all aerodromes have the volume or type of traffic which necessitate the provision of Air Traffic Control Service, at some aerodromes it may suffice merely to provide AFIS.
2.3 ICAO ATS Planning Manual Doc 9426 states:
“In connexion with the problems created by the mixture of IFR and VFR flights around busy aerodromes, some States have instituted an “air traffic advisory service” to VFR flights which is intended to:
a) keep such flights separated from IFR flights operating in the same general area;
b) provide them with advice on the conduct of their flight and other VFR traffic operating in their vicinity. Such service is extended to reduce potential risks of collision without the need to impose too restrictive conditions on VFR flights. Should this service become more widespread and thus acknowledged by ICAO, it could change the fundamental concept of the air traffic advisory service.”
2.4 In ICAO Air Traffic Services Annex 11, para 2.4, ICAO specifies the determination of the need for air traffic services considering:
“a) the types of air traffic involved;
b) the density of air traffic;
c) the meteorological conditions;
d) such other factors as may be relevant.”
The document also states:
”Due to the number of elements involved, it has not been possible to develop specific data to determine the need for air traffic services in a given area or at a given location.”
It should be noted that ICAO Air Traffic Services Annex 11 criteria are used to determine the need for air traffic services rather than the level of such a service.
2.5 According to ICAO, contracting States have the responsibility for establishing and providing air traffic services in accordance with the provisions of ICAO Annex 11 Air Traffic Services:
“States shall designate the authority responsible for providing such services.”
2.6 Following discussions by Eurocontrol’s Strategy and Policy Group (SPG) regarding the airspace in which some Commercial Air Transport (CAT) operators fly and the level of ATS provision for such flights, the SPG was tasked by the Safety Regulation Commission (SRC) to develop a matrix to determine the situation in Europe. A questionnaire was developed, aiming at eliciting relevant information regarding all airports published as available for international CAT flights. The States concerned all reported using the ICAO criteria, but it became clear that there was a big difference in the determination of the type of ATS provision; a range of airspace classification from Class C to G exists around CAT airports, indicating an extreme variation in the level of service provided. This indicates that in most cases, in line with the philosophy of Annex 11, a degree of flexibility is applied when using the criteria to take account of the myriad of factors that influence the determination of the need and level of ATS.
2.7 In Annex 11 Air Traffic Services, para 2.26, ICAO requires that:
“States shall implement systematic and appropriate ATS safety management programmes to ensure that safety is maintained in the provision of ATS within airspaces and at aerodromes.”
2.8 According to ICAO PANS-ATM Doc 4444 Chapter 2 (ATS Safety Management):
“States shall ensure that the level of air traffic services(ATS) and communications, navigation and surveillance, as well as the ATS procedures applicable to the airspace or aerodrome concerned, are appropriate and adequate for maintaining an acceptable level of safety in the provision of ATS.”
The requirement in respect of services, systems and procedures applicable to airspaces and aerodromes should be established on the basis of a regional air navigation agreement in order to facilitate the harmonization of ATS in adjacent airspaces.
To ensure that safety in the provision of ATS is maintained, the appropriate ATS authority shall implement formal and systematic safety management programmes for the air traffic services under its jurisdiction. Where appropriate, ATS safety management programmes should be established on the basis of a regional air navigation agreement.
2.9 Economic reasons force Air Traffic Service Providers (ATSPs) to reduce costs. In some events this can result in a downgraded level of ATS or situations where a higher level of service would be appropriate but will not be provided due to higher costs.
Due to the economic influence, some ATSPs have decided, in order to reduce costs, to provide different levels of services at one particular aerodrome. The change of level of service at certain times of the day, or day of the week can result in confusion to users. It is conceivable that this could result in misunderstanding by pilots for example in the responsibility for separation between aircraft.
2.10 Changing the level of ATS in Flight Information Regions (FIRs) or at aerodromes during the day can lead to misunderstanding to users and adjacent centres. In addition incorrect use of phraseology may confuse pilots as to the quality of service they can expect.
For example an Aerodrome Flight Information Service Officer (AFISO) should never use the term “radar contact” which implicates that radar service is provided.
2.11 At the same time some airline operators start operations at aerodromes with a lower level of service, like AFIS, in order to operate as cost-efficiently as possible.
2.12 At the IFALPA Conference 2006 in Istanbul, IFALPA policy regarding the need for ATS and non- availability of an adequate ATC system has been discussed. IFALPA concluded that, as no development has occurred affecting its validity, the policy be renewed unchanged for the period of two years.
IFALPA policy is:
DETERMINATION OF THE NEED FOR AIR TRAFFIC SERVICES NON- AVAILABILITY OF AN ADEQUATE ATC SYSTEM
When an adequate A.T.C. System (see ‘Definitions’) is not available in a given area, or at a given location, all commercial flying there should cease. Limited flying may be conducted where necessary in accordance with a contingency plan conforming to the principles as set out below.
Where there is a Member Association based in the State not providing an adequate ATC system, such Member Association should attempt to monitor the situation and take steps to advise the Principal Officers, in order for the latter to determine upon appropriate action to be taken by the Federation not excluding that provided for under para. B 3.2 of the I Manual.
Should, in the professional opinion of the Principal Officers, deficiencies in a specified area endanger civilian air traffic, it will at such time be the duty of the Federation to make use of all appropriate news media to keep the public informed that any air services into or over the affected areas are being carried out under conditions which IFALPA considers to be unsafe and are therefore being conducted against the Federation’s advice.
2.13 IFATCA policy is:
|“Air Traffic Control service must be provided at aerodromes that:
a) serve commercial air transport operations, or
b) have published IFR approach, departure or holding procedures.
At aerodromes at which Air Traffic Control is provided the appropriate grade of controlled airspace should be provided.
Where the above factors do not apply Aerodrome Flight Information Service (AFIS) may be provided, but shall never be used as a substitute for Air Traffic Control Service. Where AFIS is in operation the limitations of the service shall be added to the station RTF callsign.”
Due to the fact that airline operators are starting for economic reasons to operate at aerodromes with cheaper landing fees and lower ATC charges, it does not seem to be realistic to maintain the first part of the Policy. In addition it is hard to defend the requirement for provision of ATC for only a very small number of CAT movements or if the operators prefer no ATC service. Further more it should be possible (with published IFR procedures) to provide AFIS to IFR traffic if control is not required to ensure separation with other traffic. Therefore it would be better to come up with arguments that would uphold the claim for ATC. This claim can be easily defended when control is required to ensure the safety of air traffic.
3.1 ICAO is not prescriptive when it comes to determining the level of air traffic services. It remains the responsibility of the States to ensure that the required level of air traffic services provided in flight information regions and at aerodromes is achieved.
The level of service should be determined according to the standards mentioned in ICAO Air Traffic Services Annex 11, and should not be introduced through recommendation by any third party (i.e. airline operators). The level of service should meet the appropriate safety levels and should not be reduced due to costs or lack of qualified ATC-staff.
3.2 Regarding the problem DATCA was experiencing it is the opinion of TOC that the recommendation for only one service at a particular aerodrome is not required as long as the appropriate safety levels are met. Nevertheless the proposed Policy will support DATCA in their struggle to achieve the required level of ATS. The proposed Policy demands ATC when IFR procedures are published and control is required to ensure safety of air traffic. This should justify the demand for ATC service at the aerodrome where DATCA was experiencing problems. If at a particular aerodrome more than only one service is provided, it is the responsibility of the designated authority to ensure that it is clearly explained to users and adjacent centres so that no misunderstandings exist as to the quality of service they can expect. ATS staff should use the appropriate phraseologies and station callsign related to the operational position which indicates what level of air traffic service is being provided.
3.3 An ATS Safety Management System (SMS) programme should ensure that the appropriate level of safety is achieved and maintained. Therefore, the appropriate ATS authority should implement formal and systematic safety management programmes for the air traffic services under its jurisdiction. Where appropriate, ATS safety management programmes should be established on the basis of a regional air navigation agreement.
3.4 When reviewing the Policy, TOC decided that the present policy had to be amended. The demand for ATC based only on the fact that IFR procedures are published or commercial air transport needs service is not realistic. Especially if commercial air transport sometimes prefer to operate without ATC, due to more expensive charges. If control is required to ensure the safety of air traffic this is an argument that will uphold the claim for ATC. Although TOC recognizes the fact that present Policy reflects the desire for the most ideal and safest situation, it is the opinion of TOC that IFATCA has to be realistic in drafting Policy.
It is recommended that;
4.1 IFATCA Policy on page 3224 of the IFATCA Manual:
“Air Traffic Control service must be provided at aerodromes that :
a) serve commercial air transport operations, or
b) have published IFR approach, departure or holding procedures.”
4.2 IFATCA Policy is:
“Air Traffic Control service shall be provided at aerodromes that:
- have published IFR approach, departure or holding procedures, and
- where control is required to ensure the safety of air traffic.”
and is included in the IFATCA Manual on page 3224.
ICAO Air Traffic Services Annex 11.
ICAO PANS ATM Doc 4444.
ICAO ATS Planning Manual Doc 9426.
EUROCONTROL’s Strategy and Policy Group (SPG).
IFALPA policy established at the Conference 2006 in Istanbul.
ICAO Circ. 211-AN/128.
Last Update: September 29, 2020