Airservices is a government-owned corporation providing safe, secure, efficient and environmentally responsible services to the aviation industry. We manage air traffic operations for around 75 million passengers on more than three million flights every year.

Airspace Infringement

An airspace infringement (AI) is the unauthorised entry of an aircraft into airspace where a clearance is required, or to which entry is prohibited.

In an AI, there is the potential for your aircraft to operate in unsafe proximity to other aircraft. An AI may also increase air traffic control (ATC) and pilot workload and result in delays to other aircraft.

Airservices has developed a Safety Net detailing several practices which may help you avoid an airspace infringement.

Pre-flight

Thorough pre-flight preparation is a good defence against an airspace infringement. By solving potential problems on the ground, the likelihood of an airspace infringement is reduced.

Ensure you have current airspace charts

Make sure that you have current charts to cover your entire operation. Consider Control Area (CTA) steps along and around your planned route.

Charts can be purchased from the Airservices online store or from one of our resellers.

Descriptions of the various charts available for your operation are available on the Document and Chart Descriptions page.

Thoroughly familiarise yourself with local airspace and other aeronautical issues

Use your charts to study your planned route, and any possible diversions that may occur.

The Civil Aviation Safety Authority (CASA) provides a number of good reference materials to assist in pre-flight planning:

Brief yourself on restricted area activations for your planned route, including NOTAM briefing

Briefing of NOTAM, Restricted areas and weather is available through the Pilot Briefing Service.

For an easy to read display of current Restricted area status, please use the Restricted Area Briefing feature of NAIPS. (Please note that this tool only shows the status of Restricted areas: military CTR/CTA is not included.)

Consider the navigation tolerances that apply to your proposed route and level

When operating as a VFR pilot in Class G or E airspace, you must apply appropriate tolerances to your flight path to ensure that controlled airspace, or Restricted areas, are not infringed.

These tolerances vary depending on your method of navigation and your altitude and are found in AIP ENR 1.1 -40 para 19.12 –‘Avoiding Controlled Airspace’.

Submit a flight plan prior to departure if requesting a clearance

Regardless of whether or not you intend to enter controlled airspace during your flight, submitting a flight plan prior to your flight will speed up the availability of an airways clearance and the provision of assistance by ATC if you need it.. For example, if you are intending to remain outside of controlled airspace, but then need to divert around weather and enter controlled airspace, it is a lot easier for ATC and you if you have already submitted a flight plan than it is to submit one via radio.

In-flight – Navigation

Always accurately know your position relative to the CTA steps.

Verify your position if you unexpectedly arrive well ahead of, or after your anticipated time of arrival at a waypoint.

If in doubt, ask for navigation assistance from ATC (if you’ve got a flight plan submitted, this will be a lot quicker and easier).

Remember the applicable navigation tolerances while navigating visually. It is better to have definitely passed a CTA step by a couple of miles before commencing climb than hugging the CTA steps and causing uncertainty to the controllers monitoring that airspace. Similarly, make sure you set up and fly your descent profile to arrive underneath any CTA steps well before the step boundary.

In-flight – Avionics

Transponder

Ensure your transponder is serviceable before you fly.

Set your transponder to ON/ALT. If a specific code has not been given to you by ATC,(for VFR flights) set code 1200 in Class E or G airspace and code 3000 in Class D airspace. Operating your transponder will make your aircraft and altitude visible to ATC, allow air traffic controllers to receive conflict alerts involving your aircraft, and allow larger aircraft to receive Traffic Alert and Collision Avoidance System (TCAS) advisories. Additional guidance on transponder codes and requirements is available in AIP ENR 1.6 – 7.

Make sure you know how to operate the IDENT (sometimes SPI) function of your transponder. However, do not operate it unless directed to do so by ATC.

Global Positioning Systems (GPS)

GPS can only be used as the primary means of navigation if the system installed has been approved by CASA and you operate the system in compliance with this approval. If you don’t meet these requirements, your GPS can only be a secondary navigation reference.

When using GPS don’t forget to apply the appropriate tolerance for your primary navigation method to ensure you remain clear of controlled airspace. More information on tolerances to remain outside of controlled airspace is found in AIP ENR 1.1 – 40 para 19.12.

Be aware that CTA steps are generally based upon the location of the DME at the parent aerodrome, whereas GPS often uses the aerodrome reference point (ARP) which might be a couple of miles away from the DME. If using GPS to remain clear of CTA, ensure you are using the correct reference point and add the applicable tolerances.

Where surveillance (radar or ADS-B) is available, controllers normally monitor aircraft as they approach CTA steps to anticipate potential airspace infringements. If you are flying toward a CTA step with the intention of turning to parallel the step at the last moment, this will cause concern to the controller as they may anticipate that you will continue on the same track. A better technique would be to start your turn well before the CTA step. Also, if the controller is aware of your intentions, through your communication or an active flight plan this will reduce some of their concern.

Radio use

Actively monitor the appropriate area radio frequency whenever possible and listen for transmissions that include your callsign, or that are directed to unidentified aircraft in your area. ATC may direct calls to you based upon your position, altitude or heading. Speak up if you think a transmission may have been directed to you.

In-Flight – Air Traffic Control (ATC)

Use air traffic control

Controllers are there to help you. It is much better to ask ATC for help than to have an airspace infringement.

‘Flight Following’ is an ongoing Surveillance Information Service (SIS) available to VFR flights in Classes E and G airspace. This service is provided to improve situational awareness and assist pilots in avoiding collisions with other aircraft. It is available on request, but always subject to ATC workload.

Remember: ask ATC for help if you are in doubt about anything!

Requesting clearance

You should request a clearance at least five minutes before reaching the CTA step. Have an alternative plan and a suitable decision point if you do not receive clearance, or are unable to call prior to the point you would enter controlled airspace.

Having a flight plan already submitted greatly increases the chances of getting a clearance, as taking flight details over the air is time consuming and increases controller workload.

Airspace Infringement Hotspots

Generally, Airspace infringements do not occur at random locations. They frequently occur in the same areas and these are known as ‘hot spots’.

Sometimes these ‘hot spots’ are in critical locations, where an airspace infringement can interfere with the processing of traffic in controlled airspace.

Below are links to diagrams that show the location of the airspace infringement hot spots in the major basins. These hot spot diagrams also provide advice on what you can do to avoid having an airspace infringement in these locations.

Airspace Infringement Survey

Airservices and the Australian Defence Force are committed to improving safety in and around controlled and Restricted airspace for all users. To support this work we are conducting an ongoing national review of airspace infringements (AI) also known as violations of controlled airspace (VCA).

Nearly all AI reports are generated by Air Traffic Controllers (ATC). To allow all aspects of safety performance to be examined, it is important to capture as many perspectives of an incident as possible. The information gathered through reviews and feedback from all involved parties will better enable Airservices to make recommendations for changes required (if any) to procedures, training, or airspace design.

If you have been involved in an Airspace Infringement, you will receive a letter from Airservices and a request to complete an online Airspace Infringement survey.

The survey should take no more than 15 minutes to complete; although the more information you provide us, the more helpful your response will be. Your assistance by completing the survey is greatly appreciated.

Confidentiality

In completing this survey, your confidentiality is assured. Any reports generated from the information you supply will not include any personal details that would allow any person or external company or agency receiving the report to identify you. The review team will be analysing for trends, trigger events and issues – not individual performances. No action will be taken against you by Airservices on the basis of the information you provide.

De-identified survey summary reports will be provided in appropriate industry safety newsletters and magazines and will be used to target safety programs and promotions to address the most pertinent issues to all airspace users.

For further information, or to supply feedback on this survey process, please contact:

Safety Services
Email: safety.promotions@airservicesaustralia.com
Ph: (03) 9280 6202

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