The reporter expressed a safety concern regarding noise abatement procedures continuing to take priority over safety at Perth Airport.
The reporter stated that despite the windsock at both ends of runway 21 showing a tailwind of greater than 5 knots, the ATIS stated that the tailwind component was 5 knots and the duty runway was specified as Runway 21. During the actual take-off run, the tailwind was recorded on the aircraft's FMS/IRS as 6-7 knots and the actual tailwind increased to 15-20 knots almost immediately after take-off.
The reporter stated that even though pilots have been informed that they can request a different runway for operational reasons, in reality this is completely impractical due to the delays which would be incurred.
Operator's response (Operator 1)
Airservices clarifies that air traffic control (ATC) are required to comply with the noise abatement procedures contained in the Aeronautical Information Publication (AIP) and published Perth departure and approach procedures (DAP). Section 1 of the Perth DAP, indicates that Runway 21 is the preferred runway for departures.
Airservices notes that the selection of a runway in use is also governed by the instructions stipulated in Chapter 12-15 of the Manual of Air Traffic Services (MATS). Specifically, MATS Section 12-15-230 states that when runway conditions are completely dry the controller may nominate a runway with up to 5kts of downwind including gusts. The noise abatement procedures contained in the Perth DAP are not covered by location specific regulations and hence the 5kts of downwind is the maximum wind limit permitted at Perth Airport unless an alternative runway is not available.
In order to respond to the reporter's concern, Airservices reviewed 753 automatic terminal information service (ATIS) broadcasts delivered by Perth ATC over a one month period. The review analysed the Perth ATIS broadcasts against aerodrome routine meteorological reports (METAR) and aviation special meteorological reports (SPECI) produced by the Bureau of Meteorology (BOM).
Airservices has not identified evidence of systemic issues concerning runway selection at Perth Airport with the majority of Perth ATIS broadcasts aligning with the wind data provided in the BOM reports. However, Airservices notes that 15 ATIS broadcasts of 753 reviewed were identified as being inconsistent with the wind data provided in the BOM reports.
These occurrences have been raised with Perth ATC management who have reinforced runway selection requirements with Perth ATC staff. Perth management also advised that ATC staff are aware that they are required to include wind gusts in their runway downwind measurements in order to accurately give consideration to changing the selected runway if wind gusts exceed 5kts as per the MATS runway selection criteria.
Regulator's response (Regulator 1)
CASA has reviewed the REPCON and notes the action taken by Airservices to investigate and mediate the findings.
CASA's oversight of Airservices will include a review of the use of automatic terminal information service broadcasts in future surveillance activity.