Coral approach airspace design – ongoing concerns

Multiple reporters have approached the ATSB raising ongoing safety concerns in relation to the Coral Approach airspace design.

One reporter states, '[Operator] is continuing to get verbal and written reports of problems with Coral Approach airspace. General aviation (GA) aircraft are still being denied clearances or "recommended" to remain outside controlled airspace (OCTA), descend to 1,000 ft or below and call tower'. The reporter further states, 'There is still confusion from Coral Approach controllers about Class C and Class D boundaries and procedures, including allowing pilots to be responsible for their own separation in Class D'.

The reporter advised local pilots are avoiding the airspace which they believe is contributing to recent incidents. 

The reporter further advised, despite recent progress with Airservices Australia (AsA) around Temporary Restricted Areas (TRAs), phone call permission for flight training operations has returned via Notice to Airmen (NOTAM) at times, as in the example below.

B36/24

TRAINING FLIGHTS (OTHER THAN CIRCUIT TRAINING AND TRANSITS TO AND FROM THE TRAINING AREA NOT ABOVE 1000FT) AND SURVEY FLIGHTS ARE RESTRICTED AT MACKAY DUE OPERATIONAL RESTRICTIONS

PRIOR APPROVAL REQUIRED ON (07) 3866 3306

FROM 09 262254 TO 09 270830

The reporter acknowledges efforts have been made by AsA over the past 3 years since the new airspace was introduced to improve the TRA/Traffic Information Broadcasts by Aircraft (TIBA) concerns. Specifically, changing the TRA airspace design to be more user friendly, not requiring phone permission and reducing frequency of the TRAs. However, there has been no improvement on the airspace design during 'normal' operations. Consensus among many local pilots and visiting airline pilots is to change the airspace back to how it was previously with tower controllers managing airspace up to 4,500 ft. This will simplify, standardise and make safer the airspace around Mackay.

The reporter states, the CASA airspace review in 2019 for Rockhampton and Mackay recommended no change. Conclusion from the preliminary airspace review of Rockhampton and Mackay conducted by CASA in 2019 is below;

The conclusion of this Preliminary Airspace Review of Rockhampton and Mackay is that the airspace requires no change. The review considered this airspace both during activated tower hours and the evening periods falling outside these times (2300 hrs–0600hrs) when the tower was not staffed. Analysis of incidents and traffic numbers were also considered and determined that the airspace and the level of ATC service provision was appropriate and fit for purpose.

There may be opportunity to consider airspace reclassification during the periods of tower de-activation at Rockhampton and Mackay. To determine any reduction in Airspace classification or removal of air traffic services a further detailed study would be required to further scrutinize the traffic data using this airspace outside tower hours. Analysis of flight plan or radar data would be required to assist considering this potential change. However, any changes may need to consider the potential impact on Government policy, with respect to the Minister’s intent of requiring CASA to work with Airservices and the Department of Infrastructure and Regional Development (the Department), to enhance the level of controlled airspace in Australian airspace including at major regional airports.

A reporter provided the following examples of Coral airspace concerns:

'Yesterday I was flying back from Proserpine at 3,500 ft and requested clearance from Coral Approach. Despite there being no traffic in the Mackay Coral Approach airspace I was asked to remain below the control area (CTA) steps, descend to 1,000 ft and call tower directly for a clearance. (Photos of terrain clearance when at 1,000 ft inbound from the west/north of Mackay remaining below the steps supplied to the ATSB and CASA). When I queried why a clearance was not available, the controller cited military traffic in the Shoal Water Bay area (near Rockhampton) – I assume increasing [their] workload to a level to not be able to provide a clearance. A similar occurrence happened on [date] with the controller citing "outbound traffic" from Mackay which was a single Dash-8 backtracking the runway for a departure north-west.'

The reporter provided a photo (supplied to the ATSB and CASA) for a diversion to the east to avoid the worst of the terrain. The reporter states, 'Lower levels reduce safety margins for GA aircraft entering and leaving Mackay particularly if there is a power loss or reduced visibility. This has been raised formally numerous times with no progress on change'.

The reporter would like to make mention of ATSB investigation AO-2023-052 VFR into IMC, loss of control and collision with terrain involving SOCATA-Groupe Aerospatiale TB-20, VH-JTY, 65 km west of Mackay Airport, Queensland, on 28 October 2023 | ATSB, published on 2 October 2024, referencing the ‘Selection of route’ section on page 8 as evidence that local pilots are avoiding controlled airspace:

Selection of route

'…The pilot was known to plan routes that were outside controlled airspace (Figure 8). Witnesses interviewed advised this was common practice among local pilots due to the potential of encountering delays in access to controlled airspace in that region'.

The reporter finally states, 'Please understand [Operator] cannot stand idly by while these conversations are happening amongst our pilots. There is also evidence from [Airline] pilots about confusion when coming to Mackay. The implementation of the new airspace design continues to be dangerous and needs to be addressed ASAP'.

Another reporter provided a recent example below relating to Coral airspace procedure confusion:

'I was planning on tracking through Mackay Class D airspace from Palmyra airfield to Slade Point for a private scenic flight. There were no NOTAMs regarding instructions or clearance for entering and transiting through the airspace, only NOTAMs stating the Mackay tower was closed, the airspace was to become Class G and broadcast on 124.5. The Mackay automatic terminal information service (ATIS) confirmed information Zulu. Due to clearances being hard to get from Coral Approach for short flights, which I was conducting, I was limited to flying below 1,000 ft. At 6 NM west of Mackay, I broadcasted on 124.5 my position and intentions as required. I was also aware of an [aircraft] operating within the area, which was not a problem as we both made our mandatory radio calls allowing me to keep separation. For better traffic awareness even thought there was not a lot, I also was monitoring Coral Approach. And, due to my aircraft being equipped with an Automatic Dependant Surveillance - Broadcast (ADS-B) transponder, the Coral Approach controller was aware of my position. The controller then made a broadcast to an aircraft 5 nm from Mackay to contact them. This was obviously directed to me, so I made a broadcast to the controller identifying myself. They then questioned my intentions. Upon giving them my intentions, they ordered me to track to where I was heading, remain outside of the control area and contact them for clearance to transition back to Palmyra once I was finished the scenic flight over the water. Giving me this order to remain clear and contact them for clearance confused me as I was below 1,000 ft and the area had reverted to class G as per NOTAMs. If it had reverted to class D I was still operating within the regulations for that class of airspace. Once finished over the water, I contacted them for clearance back to Palmyra not above 1,000 ft which they granted me. I don’t believe they had jurisdictions within this airspace and I was capable of maintaining visual separation from other aircraft. There was only one jet departing Mackay within this timeframe. Since I was operating and broadcasting on Coral Approach frequency, it limited my ability to make the mandatory broadcast required on 124.5 for aircraft that may not have been monitoring Coral Approach, possibly due to not needing to. Once I was 6 NM west of Mackay, I was approved to change frequency and I was informed that it was unknown whether the Mackay tower would be open the following day and if not, and to contact Coral Approach for clearance through the airspace'.

The reporter advised they were confused as to why ATC instructed them to remain OCTA below 1,000 ft when they were operating in class G airspace under Common Traffic Advisory Frequency (CTAF) procedures.

Another reporter states, 'With the change of airspace to have the Tower now only up to 1,000 ft and Coral Approach above it, we now only ask for “not above 1,000 ft” for our clearances in and out of towered airspace to avoid having to place a flight plan in for every VFR flight or transit'.

The reporter provided an example regarding a breakdown in VFR separation when they had to reject a take-off from a helicopter landing site (HLS) as VFR traffic went straight over their aircraft while transitioning not above 1,000 ft. The reporter advised if they had continued the take-off, there would have been a very high risk of collision. 

The reporter provided a suggestion to further improve aviation safety of airspace surrounding Mackay:

The inclusion of a danger area or 'hot spot' marking for 'increased aircraft traffic' in the vicinity of Hay Point and nearby anchorage areas could be marked on the Mackay Visual Terminal Chart (VTC) and En-route Supplement Australia (ERSA). This should also include the requirement for aircraft transiting or operating within the danger (or hot spot) area to broadcast on and monitor VHF frequency 126.7. 

The reporter is further concerned of the potential breakdown of separation when transiting in and out of Palmyra where aircraft may be conducting circuits at 1,000 ft. The reporter advises that reverting the airspace back to a 1,500 ft limit for tower would potentially help to alleviate this issue.

ATSB comment

The ATSB notes Coral Airspace design concerns have been previously raised in REPCON RA2023-00099 - Coral approach airspace design | ATSB.

Airservices Australia responded to this REPCON advising that a trial contingency plan commenced on the 3 August 2023 - see below:

'The new trial Contingency Plan addresses specific concerns raised in the REPCON, including enabling the Tower to control access into the TRA on normal Air Traffic Service (ATS) frequencies, instead of by phone via the Contingency Response Manager. Additionally, the Tower provides a Flight Information Service (FIS) within the TRA, rather than the use of TIBA. The Tower will retain the Control Zone to facilitate low level Visual Flight Rules (VFR) traffic entering and leaving the airport without having to enter the TRA or seek prior approval, not dissimilar to how airspace is accessed if the TCU is available'.

A reporter queries the effectiveness of the trial considering the feedback they have received from multiple pilots collectively stating there has been no improvement to the concerns raised in RA2023-00099.

The ATSB notes the CASA response to the same previous Coral Airspace REPCON:

'CASA encourages airspace users to provide detailed feedback to Airservices on the adequacy of the revised procedures'. In relation to contingency procedures - 'CASA encourages the reporter to provide detailed feedback to Airservices if they continue to experience issues with services during periods when contingency practices are not in effect'.

One reporter states, some local pilots are reluctant to report their concerns or experiences associated with Coral Airspace due to the fear of potential negative repercussion from ATC. The ATSB queries if AsA has a facility for reporters to report confidentially?

The ATSB also queries if AsA has received similar concerns relating to Coral airspace in the vicinity of Rockhampton?