5.2.4 Indirect regulatory requirements affecting a visual surveillance system

In addition to the above-mentioned primary/direct regulatory requirements, there are some regulatory requirements on the service provision that may be indirectly applicable to the visual surveillance system. For conventional tower operations, they are fulfilled as per the principle ‘you see what you see’. However, for the remote aerodrome ATS context, these requirements need to be considered. This section lists such relevant provisions of Regulation (EU) 2017/373 [4] and ICAO Doc 9426. It is important to note that Regulation (EU) 2017/373 [4] and ICAO Doc 9426 only address aerodrome ATC service in details, and not AFIS. However, this guidance extends the association of the relevant provisions to AFIS as well, where appropriate, and not in contradiction with the objectives and the principles of Flight Information Services. Point (a) of AMC1 ATS.TR.305(a)(7) to Regulation (EU) 2017/373 [4] states: ‘Whenever an abnormal configuration or condition of an aircraft, including conditions such as landing gear not extended or only partly extended, or unusual smoke emissions from any part of the aircraft, is observed by or reported to the aerodrome air traffic controller or the AFIS officer, the aircraft concerned should be advised without delay. Also, Regulation (EU) 2017/373 [4], ATS.TR.400 details the aerodrome control towers responsibility and the circumstances for when to alert rescue and firefighting services. Hence, it should be considered, as part of the local safety assessment, whether the visual surveillance system needs to enable the ATCO/AFISO to visually detect and recognise aircraft abnormal configurations or conditions, such as landing gear not or only partly extended or unusual smoke emissions from any part of the aircraft. As the Regulation states that this could likewise be reported to the aerodrome controller, this needs to be defined at the local implementation level. Point (a) of AMC1 ATS.TR.205(c) to Regulation (EU) 2017/373 [4] states: ‘Aerodrome control towers should issue information, instructions and clearances to aircraft under their control to achieve a safe, orderly and expeditious flow of air traffic on and in the vicinity of an aerodrome with the objective of preventing collision(s) between: (…) (5) aircraft on the manoeuvring area and obstructions on that area.’ Although the Regulation does not explicitly state that an ATCO needs to visually see/detect obstructions (the existence of an obstruction could likewise be reported to the ATCO/AFISO), there is an expectation on the service that obstructions (of a certain size, up to a certain distance and subject to the visibility and daylight conditions) can be visually observed/detected by the ATCO/AFISO. Therefore, as part of the local implementation and safety assessment, it should be considered whether and to what extent the visual surveillance system needs to enable the ATCO/AFISO to visually detect and recognise obstructions on the manoeuvring area. Local operational requirements should be defined, taking into account size and distance of obstructions, as well as under which daylight and meteorological conditions the requirements are to be valid. As concerns obstructions, GM1 to AMC16 ATS.TR.210(a)(3) to Regulation (EU) 2017/373 [4] states: ‘Animals and flocks of birds may constitute an obstruction with regard to runway operations.’, and point (b) of GM1 to AMC1 ATS.TR.305(a)(5) to Regulation (EU) 2017/373 [4] states: ‘Essential information on aerodrome conditions shall include information relating to the following: (…) (5) other temporary hazards, including parked aircraft and birds on the ground or in the air;’. Note: The SESAR JU validations has shown ‘visual tracking’ (refer to Section 5.2.8) to be a useful tool to support the detection of the occurrence of birds/flocks of birds. Point (b) of AMC12 ATS.TR.210(a)(3) to Regulation (EU) 2017/373 [4] states: ‘Prior to take-off, the aerodrome control tower should advise aircraft of: (…) (2) significant meteorological conditions in the take-off and climb-out area, except when it is known that the information has already been received by the aircraft.’ Therefore, it should be considered whether the visual surveillance system needs to enable the ATCO/AFISO to visually observe some significant meteorological conditions in the take-off and climb-out area (subject the type of and distance to the significant weather, the daylight/darkness conditions as well as the meteorological visibility). Although the responsibility for the monitoring of the condition of the movement area and reporting on matters of operational significance to the ATS provider lies with the aerodrome operator (ADR.OPS.B.015 of Regulation (EU) No 139/2014 [7]), the ATS provider may want to consider whether and to what extent the visual surveillance system should support the ATCO/AFISO to visually observe/detect runway surface states and their changes, such as those conditions listed in points (b)(2) to (b)(5) of GM1 to AMC1 ATS.TR.305(a)(5) to Regulation (EU) 2017/373 [4]. Paragraph 1.4 of Appendix 1 to AMC1 SERA.14001 to Regulation (EU) 923/2012 [86] ‘Phraseologies for use on and in the vicinity of the aerodrome’ defines the following means of visual communication with aircraft: showing landing lights as a possible means for ‘identification of aircraft’ (1.4.1); moving ailerons (or rudder), rocking wings or flashing landing lights as a possible means for ‘acknowledgement by visual means’ (1.4.2). As a consequence, the implementation of remote provision of aerodrome ATS should consider, as part of the local safety assessment, whether and to what extent these indirect regulatory requirements should form operational requirements driving the technical requirements for the implementation. As for a conventional tower, the fulfilment of such requirements will be dependent on the distance from the aircraft and on meteorological and daylight/darkness conditions.