5.2.7 Functional considerations for a visual surveillance system

In addition to the regulatory requirements and the operational needs described above, factors related more directly to system performance should be considered when moving to a ‘remote’ environment, as they will affect the performance of the visual surveillance system and subsequently also the operational capabilities of the ATS unit. The performance and usability of the visual surveillance system is a complex combination of many such system performance factors. Some of them found to be particularly critical for the ATCO/AFISO ability to perform the ATS are discussed below, but as indicated under Section 5.2.7.6 ‘Other image quality factors’, they are not the only which may be affecting remote aerodrome ATS provision. Because of this complexity, as already mentioned under Section 5.2, it is essential that the visual surveillance system is operationally validated against the perceived total image quality, rather than against specific image quality factors.