While jet aircraft usually fly on published flight paths, turbo-propeller or turbo-prop aircraft (non-jet) have a range of different performance capabilities and therefore fly in a range of ways.

Some turbo-props fly on the published instrument arrival flight paths, while others use the published visual approaches which includes vectoring from air traffic control (ATC).

Turbo-prop departures are allocated headings by ATC based on their destination. This is to keep them safely separated from jet operations, due to differences in aircraft capability (for example speed and altitude of operations), and to maintain a steady flow of traffic.

This means we see a broad area where turbo-props may fly.

Impact of COVID-19 on aircraft operations

Aircraft are flying in accordance with the published procedures. The impacts of COVID-19 restrictions, and the subsequent reduction in interstate jet traffic movements during border closures, resulted in a different distribution of traffic across flight paths and areas of operation.

This is because air traffic control has not needed to use parallel runway operations due to the lower traffic levels.

This has resulted in a greater spread of turbo props outside of the ’swathe’ of operations than we expected.

Turbo props use a mix of jet and non-jet flight paths including visual approaches. A visual approach is when a pilot is operating the aircraft by visual references. This approach can therefore vary by several kilometres.

Changes to turbo-prop operations

We have worked closely with Brisbane Airport to understand the safety and traffic management requirements during this period of disruption.

We will implement a temporary Noise Abatement Procedure to adjust the traffic spread to match what would have been experienced had COVID-19 not affected traffic volumes. This will increase operations in the areas between the short and long approaches (the swathe) during periods of high demand, while the shorter visual approach will still occur when traffic volumes are generally lower.

This temporary procedure will be in place until operations increase to both runways, which will then result in a similar traffic management outcome – with more aircraft operating within the ‘swathes’.

Turbo props will continue to fly visual approaches after we return to parallel runway operations, generally in non-peak times.

Arrivals

Turbo-props need to be managed to make sure they can safely arrive along with jet operations. When the airport is busier, turbo-props more commonly arrive using the published flight paths so they can be safely separated from the jet aircraft traffic by air traffic control.

As there has been low jet traffic at Brisbane airport, turbo props were able to conduct visual approaches and arrive on a more direct path to the runway from their locations.

With borders opening and traffic levels increasing to the existing runway, more turbo-prop aircraft will be required to fly on the published instrument flight paths as they are processed in parallel with jet traffic to both runways.

The image above shows pre-COVID levels of turbo-prop arrivals with traffic arriving from both northern and southern locations.

The image above shows an overall reduction in turbo-prop arrivals, with the majority of remaining flights arriving from northern (intrastate) locations to the new runway (Runway 19R/01L).

Click on the images above to open a larger view in a new tab.

Departures

Turbo-props are usually assigned a heading at the departure end of the runway, depending on their destination. You will notice that turbo-prop aircraft using the legacy runway at night are quite spread out.

With borders opening and traffic levels increasing to the existing runway, more turbo-prop aircraft will depart from the existing runway.

The image above shows pre-COVID levels of turbo-prop departures with traffic departing from both northern and southern locations.

The image above shows an overall reduction in turbo-prop departures but a wider spread, with the majority of remaining flights departing to northern (intrastate) locations from the new runway (Runway 19R/01L).

Click on the images above to open a larger view in a new tab.

Learn more about operations during COVID-19 on our Impact of COVID-19 on flight operations at Brisbane Airport page.

Note: All tracks during the stated month have been displayed. Track colours have been adjusted to show track density. Where aircraft are more concentrated the colour will appear darker.

Air traffic control manage the traffic to each runway at an airport using a range of operations which can include clearing aircraft to use published flight paths, issuing visual approaches or vectoring for separation and sequencing. As the runway in use changes, the types of operations in use will also change, and so different suburbs and areas are affected by aircraft movements.

Flight paths do not operate in isolation. They are part of an interconnected network. Flight paths need to accommodate aircraft operating constraints, provide terrain clearance and fit into the overall airspace design.

Arrivals

Arriving aircraft need to align with the runway prior to touching down. Depending on the arrival or approach procedure being flown, aircraft may align with the runway from a few kilometres to beyond twenty kilometres from touchdown.

When the sky is clear and there is no low cloud along the approach path, aircraft may join the runway alignment closer to the airport. If there is low cloud or other weather impeding visual conditions, aircraft will align with the runway further from touchdown and will fly the published flight path.

A further consideration is the density of traffic. If there are frequent arrivals to both runways, aircraft will align with the runway further from touchdown in accordance with established parallel runway flight procedures.

Departures

Departing aircraft can turn once they are airborne and stabilised. Both turbo-prop and jet aircraft operate at Brisbane Airport. These aircraft types have different operational capabilities and are separated accordingly.

Departures from the new runway plan to fly to ports to the north or the west, and are required to turn. The departure procedure for turbo-prop aircraft sees these aircraft types turn at an altitude of 600 feet but not before the runway end. This is necessary to move the aircraft onto the planned route and also to move the aircraft out of the path of the faster moving jet aircraft.

Jet aircraft maintain the runway heading on departure. They do so in order to gain altitude so that when they do turn, they are higher than the propeller aircraft departures and can safely pass above them.

If turbo-prop and jet aircraft departed on the same flight path there would be more time needed between movements due to differences in the operational capabilities. This would impact the efficient operation of the airport by reducing the throughput of aircraft.

Alternative Flight Paths

The Brisbane new parallel runway operations design has certain modes of operation and generally aircraft departing to or arriving from the west or the north will land and depart on the new runway, while aircraft departing to or arriving from the south or east will land and depart on the legacy runway.

However to maximise the safety and efficiency of operations, the airspace design also includes flight paths that track from all directions to both runways. 

This provides air traffic control with the option to use these flight paths to effectively manage air traffic in high workload periods, including when there is bad weather, runway maintenance or an emergency, or in periods of air traffic delays, including holding.

Learn more about how the runways are selected on our Brisbane Airport Runways page.