Preliminary report


Preliminary report

Published: 22 September 2017

On 26 January 2017, the pilot of a Grumman American Aviation Corp G-73 amphibian aircraft, registered VH‑CQA (CQA), was participating in an air display as part of the City of Perth Australia Day Skyworks event. On board were the pilot and a passenger. The weather was fine with a recorded wind of about 20 km/hr from the south-west and a temperature of about 39 °C.

The pilot of CQA was flying ‘in company’ with a Cessna Caravan amphibian and conducted a series of circuits that included low-level fly-pasts of the Langley Park foreshore (Figure 1). After the second fly-past, the pilot of CQA commenced a third circuit, while the Caravan departed the area.

Figure 1: CQA air display flight track, showing the first fly-past in yellow, the second in magenta and the third in red

Figure 1: CQA air display flight track, showing the first fly-past in yellow, the second in magenta and the third in red

Source: OzRunways Pty. Ltd., modified by the ATSB

As part of the third circuit, the pilot of CQA flew in an easterly direction, parallel with the South Perth foreshore, before commencing a left turn. This would have facilitated a third pass in a westerly direction along the Langley Park foreshore. During the left turn, CQA rolled left and pitched nose down, consistent with an aerodynamic stall[1] (Figure 2). The aircraft collided with the water and broke up. The pilot and passenger were fatally injured.

Figure 2: CQA just prior to the collision with water (looking north)

Figure 2: CQA just prior to the collision with water (looking north)

Source: Mike Graham

The ATSB completed the on-site phase of its investigation on 4 February 2017. No pre-existing aircraft defects, which may have contributed to the collision with water, were identified. The ATSB has retained several items and components from the aircraft for further examination. This includes a fuel totaliser, a navigation unit and a mobile phone.

The investigation is continuing and will include:

  • examination of numerous witness reports and images and a significant quantity of video footage taken on the day by members of the public, media outlets and so on
  • review of the aircraft’s maintenance records, operational records for recent flights and pilot training records
  • review of the meteorological conditions at the time
  • an examination of aircraft performance and other operational factors
  • further examination of the recorded flight radar, radio and Global Positioning System data
  • review of the planning, approval and oversight of the air display, including a focus on safety and risk management practices.

Should any critical safety issues emerge during the course of the investigation, the ATSB will immediately bring those issues to the attention of the relevant authorities or organisations. This will allow those authorities and organisations to consider safety action to address the safety issues. Details of such safety issues and any safety action in response will be published on the ATSB website at

Since the release of its preliminary report on 8 March 2017, the ATSB has provided an update to this investigation.


The information contained in this web update is released in accordance with section 25 of the Transport Safety Investigation Act 2003 and is derived from the initial investigation of the occurrence. Readers are cautioned that new evidence will become available as the investigation progresses that will enhance the ATSB's understanding of the accident as outlined in this web update. As such, no analysis or findings are included in this update.



  1. Aerodynamic stall: occurs when the airflow separates from the wing’s upper surface and becomes turbulent. A stall occurs at high angles of attack, typically 16˚ to 18˚, and results in reduced lift.