Mode Aviation
Reference No. AR201700120
Date reported 29 November 2017
Concern title Inconsistent Approach closure
Concern summary

The concern related to inconsistent availability of controlled airspace at Mackay and Rockhampton resulting in pilot confusion.

Industry / Operation affected Aviation: Airspace management
Concern subject type Aviation: Airspace

Reporter's concern

The reporter expressed a safety concern related to the availability of controlled airspace at Mackay and Rockhampton after the tower closes.

The reporter advised that it seems Approach control is available on an ad hoc basis and this is causing confusion to the pilots in the area.  They have heard other pilots requesting services including clearances and traffic information on the wrong frequencies when approach control is not manned - and the confusion now seems to occur even when it is manned.  The reporter is asking what is the process to determine when ATC control services are available as the increasingly ad-hoc changes seem to be confusing pilots.

With operations below 4,500 ft not being consistently controlled it is easy to see a situation where the crew of an aircraft does not realise Approach is in operation, makes all their calls on the CTAF and takes off towards an aircraft on approach, especially in bad weather to the reciprocal runway under Approach control (to 700 ft?).

This could have very serious consequences if either of us miss the other crew calls because we are on different frequencies and have not made our CTAF call yet inbound, or forgot to make the calls altogether.

Operator's response (Operator 1)

Airservices Australia (Airservices) appreciates the opportunity to respond to the reported safety concern related to the availability of controlled airspace at Mackay and Rockhampton after the tower closes.

In response to this REPCON, Airservices would like to advise the reporter the following:

The out-of-hours approach services are detailed in the AIP ERSA for Rockhampton and Mackay (refer to attachment 1 and 2). By default, a pilot should operate as per ERSA entry (i.e. Rockhampton and Mackay approach operational). Following a review into the traffic volumes and requirements/suitability of a service in the area, it was determined that approach services are not required between 13002 (2300 hours local time) until tower opening for both Rockhampton and Mackay.

This came into effect earlier this year and NOTAMs are issued on a weekly basis advising the unavailability of the approach service. There are currently 4 NOTAMs issued:

  • BN (YBBB) FIR NOTAM - Rockhampton
  • BN (YBBB) FIR NOTAM - Mackay
  • Aerodrome NOTAM - Rockhampton
  • Aerodrome NOTAM - Mackay
  • Further NOTAMs are issued, as required, when the approach service is unavailable.

As well as the published NOTAMs, details on approach operating hours are available from Rockhampton and Mackay towers during hours of operation and from Air Traffic Services on the area frequency outside of Tower hours. Pilots should refer to Outside Controlled Airspace (OCTA) procedures when tower and approach services are unavailable.

Airservices notes that aircraft neglecting to make a broadcast on the Common Traffic Advisory Frequency (CTAF) or inadvertently broadcasting on the incorrect frequency is an existing risk for all CTAF operations. It is mitigated by pilot vigilance in ensuring that radios are both operational and selected to the correct frequency.

Airservices is currently participating in a larger project which includes:

  • Implementation of RNP 1 SIDs and STARs at both Rockhampton and Mackay (now complete) these instrument flight procedures provide separated approaches and departures during tower and approach hours and segregated approaches and departures at all other times
  • A full review of the quantifiable benefits of the out-of-hours approach service
  • A review of the surrounding airspace
  • A proposal for the change of airspace classification below A045 outside of tower hours ( currently under development)

The Office of Airspace Regulation (OAR) within the Civil Aviation Safety Authority (CASA) have been included in all communications regarding this project.

Finally, Airservices has not identified any specific pilot complaints in relation to the issues raised in this REPCON.

Regulator's response (Regulator 1)

CASA has reviewed the incident database for the Rockhampton and Mackay areas and has not found evidence to suggest there is a greater risk to aviation safety arising from radio frequency confusion at these aerodromes.

Airservices Australia will issue NOTAMs to advise pilots whenever there is a change to an air traffic control approach (APP) service as published in the En-Route Supplement Australia (ERSA). The information in ERSA should ideally reflect the existing and the ongoing arrangements for the provision of communication services.

CASA will recommend that Airservices Australia consider minimising the dissemination of communication and facilities information by NOTAM and that they review and if necessary, amend the ERSA entries for the ATS Communications Facilities at Rockhampton and Mackay to reduce any potential for confusion that may arise from conflicting or differing information.

Finally CASA’s Office for Airspace Regulation (OAR) is conducting a formal Airspace Review of Rockhampton and Mackay which it will complete prior to mid-2018.

ATSB comment

The reporter provided the following comment upon reviewing the final report:

The main concern seems to go unanswered. Both Airservices and CASA address what happens when the service is not available (a NOTAM is issued) but not the process used to get to that point. In other words, when staff providing the service are sick or otherwise not available, why are they not replaced by calling out replacement staff – i.e., what is the process used to determine if the service is provided. If a NOTAM is issued, is it based on any safety work for not replacing the absent controller?

Airservices provided the following response in relation to the reporter’s comment:

We acknowledge CASA’s recommendations of reducing the dissemination of communication and facilitates information by NOTAM.

Airservices will undertake an internal review to determine the feasibility of amending the communication and facilitates information in ERSA as well as other potential options regarding NOTAM dissemination.

Last update 23 January 2019