Document ID: chunk:federal_register_of_legislation:F2024C01244:reg:5:p197
Version: federal_register_of_legislation:F2024C01244
Segment Type: reg
Provision Reference: reg 5 (pt 197/225)
Character Range: 827193–830051

interference to a minimum, for example, RF traps, use of trees and shrubs, no fences tangent to the sensor.

Note 2   For further background details on the "area of interest" for radar monitoring sites, see Guideline G of the National Airport Safeguarding Framework, as in force or existing from time to time and freely available on the CASA website.

       (2) For power lines and electrical transmissions within the aerodrome boundary which may cause interference with radar surveillance sensors, the following restrictions apply:

(a) all overhead power lines within 1 km of a radar surveillance sensor must be aligned radially from the radar or be located at least 10° below horizontal from the antenna;

(b) no radio interference emitters (for example, welders and electrical transmission lines) having any component of transmission in the radar frequency band are permitted within 2 km of a radar surveillance sensor;

(c) no overhead electrical transmission line with a line capacity mentioned in a row of column 1 of Table 19.10 (2) is permitted within the distance from a radar surveillance sensor mentioned in the same row in column 2.

     Table 19.10 (2)   Minimum overhead electrical transmission line distance from aerodrome boundary

Line capacity   Distance
2 kV – 22 kV    400 m
22 kV – 110 kV  1 km
Above 110 kV    2 km

19.11 Protection of wide area multilateration (WAM) and automatic dependent surveillance – broadcast (ADS-B) sensors

        For WAM and ADS-B sensors, the aerodrome operator must refer the following for assessment by the navigation service and facility provider responsible for the WAM or ADS-B sensor:

(a) any proposed development within a 100 m radius from the antenna base that would exceed the height (the mentioned height) that is 1 m below the sensor antenna base (the building restricted area critical zone) but excluding buildings, trees, power and telephone lines, and fences that do not project above the mentioned height;

(b) any proposed development between 100 m and 1 500 m of the sensor that would exceed an angle of elevation of 1° measured from the centre of the sensor (the building restricted area sensitive zone).

Note   Large obstructions, for example, multi-storey buildings, steel bridges and wind turbines, are potential sources of interference to correct operation. For a new installation, CASA recommends that the installation should be kept at least 1 500 m clear of these types of structures.

19.12 Protection of VHF/UHF communication facilities

Note   Reliable VHF/UHF communications require a clear line-of-sight path between the base station and aircraft and vehicles using the facilities. The construction of buildings or towers can prevent reliable communications. The Area of Interest for the VHF/UHF facilities includes all developments between 100 m and 2 000 m that exceed