5.4 Aerodrome sound

When providing remote aerodrome ATS from a location/facility where the ATCO/AFISO is unable to detect the naturally occurring sounds of the aerodrome, a function that captures and relays aerodrome sound may be introduced. The implementation of such an aerodrome sound reproduction functionality should be assessed as part of the local safety assessment, taking into account the particularities of the operational context. Particular care should be taken when selecting the aerodrome sound detection devices site. Nearby noise or impact of wind on the microphones could shield the aerodrome sound. Aerodrome sound reproduction functionality would be an enabler for increased situational awareness and could create a greater sense of presence. Such a functionality has shown to be particularly valuable for smaller aerodromes where sound could play an important role for the ATCO/AFISO, attracting their attention to arising occurrences. Aerodrome sound can increase situational awareness during e.g. low-visibility conditions and emergency situations, and it may also support weather perception. Furthermore, it could raise awareness of potential traffic outside the visual field of view provided by the visual presentation/visual surveillance system. On the other hand, today’s practice at many conventional towers is to minimise or even suppress surrounding aerodrome sound by insulating the tower cab/building. This may be the case for larger aerodromes with a high traffic volume/density or for aerodromes where the traffic involves particularly loud aircraft operations such as military jet fighters. If implemented, the volume of the aerodrome sound reproduction should be adjustable. This possibility would support the needs of individual ATCOs/AFISOs to minimise disturbing background noise when/if needed. Also, the use of aerodrome sound in an RTC set-up would need to be carefully assessed. A maximum allowable latency for the aerodrome sound should be determined, taking into account the corresponding video latency of the visual surveillance system and a possible synchronisation with it. For further considerations regarding multiple mode of operation, refer to Section 5.13.4.