36TH ANNUAL CONFERENCE, Taipei, Taiwan, 17-21 March 1997
WP No. 84
Examine the Interface Between AFIS and ATC
The implementation of Aerodrome Flight Information Service (AFIS) units has globally experienced recently a sudden growth. The main cause being the current rate of growth of air traffic and the consequent need for the maximum exploitation of the available infrastructure resources.
Extensive implementation of AFIS focuses attention on the interface between ATC and AFIS especially when co-ordination takes place.
The main rationale for this study item is to better define the “interface” to be adopted between AFIS and ATC units.
As far as IFATCA “policy” on this matter is concerned, no specific guidelines have been established. However, it is useful to draw attention to the relationship with this topic and the SC1 study item “Review provision of ATS with particular reference to airspace classification” and the professional information regarding ATS personnel
Initially 3 major aspects appear to be eligible for investigation, though limited to general considerations as shown below:
Regulatory aspects: to determine relations between AFIS and ATC. Under this topic also “co-ordination” has been covered;
Operational organisation: to determine a “model” to be used when considering the establishment of AFIS units and their relevant requirements in terms of equipment and lay-out;
Personnel: to highlight liaisons (if any) between AFIS personnel’s qualification training, rating, employment and ATCO’s.
To cover current changes in the ATS environment with considerations regarding CNS/ATM “AFIS and ATM” have been included to cover any possible development not yet considered.
An AFIS unit, as described in ICAO Circular 211 AN/128, is defined as a unit providing “useful information for the safe and efficient conduct of aerodrome traffic at aerodromes designated for use by international general aviation (IGA)”. Thus implies the exclusion of international commercial transport operations management, as stated later in the same document.
AFIS units are then tasked with the provision of FIS and Alerting service within their jurisdictional airspace ( known as FIZ established on the ATZ), without being considered an ATC unit; aerodromes identified as “AFIS aerodromes” maintain the status of “non-controlled” aerodromes.
There is the need to determine at least the total movement rate of IFR flights that could safely operate in the same time at an AFIS aerodrome. This is relevant if a transition through different classes of airspace is expected along the flight (e.g.: AFIS aerodromes whose FIZ is adjacent to a CTR)
Although no references have been made to FIZ airspace classification in the ICAO Circular, as far as FIS is considered, class “G” appears to be the appropriate classification.
It must be noted that the aims for which an AFIS unit is established is to provide aircraft wishing to receive FIS . Unless exempted by the appropriate (ATS) Authority, participating aircraft must be capable of two way communication with the AFIS unit on the prescribed frequency (or frequencies) Also to be noted is that the application of more restrictive classes of airspace would not suit the services provision of AFIS and would result in an upgrading of the service to “advisory service” or “ATC service” for IFR flights.
In examining the interface between AFIS and ATC, particular attention is drawn to coordination in that phase of flight when an aircraft – or more than one – is transiting from an AFIS to ATC and vice a versa. This is particularly relevant when FIZ is surrounded by controlled airspace where instrument procedures’ profiles extend trough both volumes of airspace.
The operation of instrument procedures, the regulation of the number of aircraft performing these procedures to/from AFIS aerodromes, the appropriate information to be passed to pilots involved, should be the subject of a Letter of Agreement to clearly determine the status of the service provided and any particular requirements to be considered between AFIS and the relevant ATC unit(s).
Assuming that an AFIS unit should be provided with all information normally given to a Control TWR (ref ICAO Circular), the relevant model is that defined in the ATS Planning Manual (DOC 9426) when configuring a “low traffic density” TWR requirements. Functional organisation should mirror structures already existing and proved to satisfy service provision requirements, coordination with other aerodrome’s units/services personnel management etc.
Importance should be given to the fact that AFIS could also be charged with activities, which are peculiar to ARO. When this occurs on a regular basis it would be necessary to define the difference between AFIS and ARO functions and relevant procedures.
As far as it’s impractical to define “low traffic density” by a specific number of movements, particular care should be exercised in order to prevent excessive/inadequate AFIS implementation.
Current documentation does not clearly state any requirement regarding qualification for AFIS personnel. Circular 211 AN/128 only provides guidelines in considering relevant knowledge, skill and experience, which appear to be similar (but not identical) to those listed in ICAO Annex I for ATCOs.
In order to avoid potential lack of standardisation in personnel selection, qualification and training, ICAO should provide more appropriate guidelines for qualification and training of AFIS personnel.
AFIS and ATM
The general objective of ATM is to enable aircraft operators to meet their planned times of departure and arrival and to achieve their preferred fight profiles with minimum constraints without compromising safety . For that ATM comprises ATS, ATFM and ASM, currently in practice in areas of high traffic density.
In this context AFIS is to be considered, as other ATS units, as a participant in the achievement of ATM goals, particularly when providing services for traffic that will be the subject of ATFM measures.
Considering ASM topics, it seems useful to underline the need for the identification of a common (at least on a regional basis) set of rules to be followed in airspace planning and organisation when AFIS implementation is involved.
It is necessary to review ICAO Circular 211, published in 1988, in the light of airspace classification, introduced in 1992 with particular reference to FIZ airspace designation.
At aerodromes where Flight Information Service is provided and directly surrounded or adjacent to controlled airspace, appropriate LOA’s are to be adopted defining the interface between AFIS and the relevant ATC unit(s) to provide detailed operating and coordinating procedures.
SC IV should review the guidelines for qualification and training of AFIS personnel as published by ICAO.
It is recommended that:
At aerodromes where Aerodrome Flight Information Service is provided and are directly adjacent to controlled airspace appropriate LOAs are to be adopted defining the interface between AFIS units and the relevant ATC unit(s) in order to provide detailed operating and coordination procedures.
Last Update: September 28, 2020