Mode Aviation
Reference No. AR201700037
Date reported 12 April 2017
Concern title Number of operator aircraft operating in the circuit at one time
Concern summary

The concern related to the number of aircraft belonging to an individual operator operating in the circuit at one time.

Industry / Operation affected Aviation: General aviation
Concern subject type Aviation: Airspace

Reporter's concern

The reporter expressed a safety concern related to the number of [Operator 1] aircraft operating in the [Location 1] circuit area at one time and the use of private departures by pilots from this operator.

The reporter advised that there are often five to six [Operator 1] aircraft conducting circuits and sometimes, there have been up to eight [Operator 1] aircraft in the circuit. This, on a number of occasions, has led to the students confusing their call signs/registrations and where they are in the circuit. This subsequently makes it difficult for other aircraft to join the circuit and to gain an appreciation of where each aircraft actually is in the circuit. These aircraft, with very similar registrations [multiple registrations], are operated by students with low experience and often English is a second language which can add to the students’ confusion, but also the difficulty for pilots in other aircraft. It was suggested that [Operator 1] would stagger their training flights in the circuit to ensure that safety is maintained, but this does not seem to be happening in recent times.

The [Operator 1] have also designed their own arrival and departure procedures (eg ‘[Name] Departure’ and ‘[Name2] Departure’) which have not been promulgated through the local aviation community or to the regular transport aircraft which operate regularly into [Location 1]. Pilots from other operators have no idea which direction the students are using to depart and arrive the circuit and what altitude they will be using. This makes arranging separation very difficult.

Regulator's response (Regulator 1)

CASA has reviewed the REPCON and provides the following comments. The operator concerned has a mature Safety Management System (SMS) and appears to be managing the issue appropriately. In addition, the CASA Office of Airspace Regulation (OAR) is prioritising a review of the airspace architecture and procedures around [Location 1]. The OAR will complete a preliminary review of the airspace architecture by mid-June 2017 to determine the level of risk and any other issues that may require mitigation to ensure safety, efficiency and equitable access for all airspace users in the region. The preliminary review will include an analysis of aircraft and passenger movements at [Location 1], a review of incident reports submitted to the ATSB and Airservices, and engagement with stakeholders to better understand the issues from an airspace user perspective. The preliminary review will provide findings that may initiate a more detailed airspace review that will recommend options to protect the safety of all airspace users.

ATSB comment

REPCON supplied the operator with the de-identified report. The following is a version of their response:

The anonymous reporter expressed concern regarding safety related matters when operating with two particular areas:

  1. Multiple [Operator] training aircraft operating in the [Location] circuit
  2. Use of private departure procedures by [Operator].

We will provide information regarding each concern.

Concern 1

[Operator 1] has a policy that we will not have any more than three company aircraft conducting circuit operations at any one time. However, this does not preclude that other company aircraft may depart, or arrive to/from the circuit from either cross-country or training area flights, as well as other local traffic and itinerant aircraft. [Operator 1] has an advanced understanding of knowing what the risks to our operations are when operating at [Location 1], we are continually monitoring the type of reports that we receive in our Safety Management System and we are proactive at alerting our instructors and students when new hazards and risks are observed. Traffic separation is the most frequent category of report that is submitted into our SMS. All of our flight instructors and students are aware that this is our most prominent risk when operating at [Location 1].

Our latest Safety Management System notice, that we send to all instructors and students, outlines our operational risk profile. We are continuously managing this issue. We have a fleet of 16 new generation aircraft, 8 of these aircraft are fitted with ADS-B out technology, and active traffic systems. We teach our students and instructors in the use of these systems, but importantly not to be reliant on these systems and use them to aid alerted see-and-avoid traffic separation, as there are numerous aircraft operating in the [Location 1] area without transponders. Our operational staff endeavour as much as possible to manage departures, arrivals and circuits, being mindful of the circuit and airspace capacity with regards to safety and efficiency. We are mindful that our operation does impact the traffic situation at [Location 1], and we are mindful that non-native English speaking students can cause complications in radio communications, we are continuously monitoring English language proficiency with our students. We believe we are operating responsibly and managing risk very effectively. The reporter, who has the convenience of anonymity, has completely overstated that at times [Operator 1] operates 6 to 8 aircraft, conducting circuits at [Location 1].

There certainly would be occasions when [Operator 1] would have that number of aircraft in the airspace (training areas, circuit area etc.) at [Location 1], however we never schedule or plan for that many company aircraft to perform circuit operations. Our company is continually receiving complaints, some of which are over the [Location 1] CTAF Frequency about our operation. All of our company instructors are directed to accommodate other operators and airline traffic as much as reasonably possible. We endeavour to not delay any other flight or interfere with other operator’s training flights. We do understand that our traffic movements do impact on other operators, and we do everything we can to ensure the airspace operates safely and efficiently. We modify circuit procedures to give way to other aircraft, and we hold on the ground to delay a departure to ensure we don't inconvenience a scheduled flight, or even a small recreation aircraft. These actions come at a significant cumulative financial cost to our organisation, however, we continue to direct our instructors and students to operate in this way as we do understand the impact of our operations with respect to other airspace users. It just seems that whatever we do, it is challenging to keep other operators satisfied.

[Operator 1] has also implemented a policy that we will not allow multiple aircraft to backtrack and occupy the runway at the same time, [Operator 1] aircraft, or [Operator 1] aircraft and another aircraft. Other local operators frequently have numerous aircraft occupying the runway at [Location 1]. We will not allow this as we see a number of potential risks with this behaviour, however we are under constant criticism from other operators about our policy, especially when runway [runway #] is in operation, with our instructors and students frequently receiving requests from other operators to enter and backtrack when our company aircraft is backtracking. We have communicated in writing to all operators at [Location 1] about this policy, and the reasons why we have this policy, which is to reduce operational risk when dealing with trainee pilots. Our instructors and students still receive requests to backtrack in tandem by other aircraft, in which all of our instructors and students politely mention that it is against company policy.

Unfortunately, this is not accepted by other operators, and some go ahead and backtrack whilst we have a company aircraft on the runway anyway. When this has happened, the [Operator 1] aircraft discontinues the backtrack, and exits the runway. A recent example of this continual pressure is in a meeting with a local operator, [Operator 2], in which the nature of the meeting was about circuit operations safety, we were again asked to reconsider our no multiple aircraft backtrack policy. We find this quite contradictory and disappointing. We are going to a great deal of effort to train professional flight crew, and demonstrate exemplar practices in safety and airmanship and we continue to receive these requests and observe unprofessional behaviours.

Concern 2

The anonymous reporter has expressed concern about [Operator 1] using private procedures and they claim that they have not been promulgated through the local aviation community. This is totally incorrect. We have provided advance notification to all operators at [Location 1], all airline operators, CASA, and the airport operator. All stakeholders provided notification that they did in fact receive these procedures, as well as other risk mitigation information we have developed. The only stakeholder that has never provided any acknowledgment that they received information regarding procedures from our organisation is the [Operator 2].


[Operator 1] will continue to closely monitor our operations at [Location 1] and [Location 2] airports with vigilance. We are continuously directing our instructors and students to actively utilise see-and-avoid separation procedures, supported by the technology we have fitted to our aircraft. Our first generation [aircraft type] aircraft will be progressively fitted with ADS-B in/out technology.

We had a meeting with another airport operator [Operator 2] to discuss more efficient use of circuit airspace. We have now changed the policy where in the past it stated that all company aircraft must use full runway length for all take-offs from both runway XX and XY. We have revised the policy so that we will now authorise intersection departures when operating from runway XY and a reduced length (1200 metres) departure when operating on runway XX, only on occasions where this will assist in airspace efficiency, otherwise, under conditions of no constraint, company aircraft must continue to utilise full runway length. We believe this will make more efficient use of the circuit and possibly reduce some risk, except to our flight crew who will now have to accept an increase of risk during take-off due to using decreased runway length, in order to please other operators. I think it is also important to note that the issue of runway [runway #] use at [Location 1] has been introduced by the airport operator in extending the runway length to 1800 metres without constructing a parallel taxiway, where a 1600 metre backtrack is now required when operating on runway [runway #].

We have been responsible in distributing operational procedure information and risk mitigation information to all stakeholders. It is possible with some of the more amateur and non-professional operators there does not exist any formal communication processes to ensure their pilots receive and are educated in this information. [Operator 1] is more than willing to communicate and provide education to any stakeholder regarding our operating procedures.

Last update 12 July 2018