Qantaslink has updated its departure procedures from some smaller airports following the near collision between a De Havilland Canada Dash 8 Q300 and a Piper PA-28 Cherokee at Mildura.
The incident, which the Australian Transport Safety Bureau (ATSB) classifies as ‘serious’, occurred on the early afternoon of 6 June 2023, and hinged on call-outs over the common traffic advisory frequency (CTAF) used between aircraft at non-towered aerodromes.
The pilot of the PA-28 (VH-ENL), preparing to take off from Mildura’s runway 36, was aware that the Dash 8 (VH-TQH) was taxiing on the intersecting runway 09 pending backtracking before take-off. The Dash 8 crew, however, was unaware of the PA-28.
The crew of the Dash 8 commenced their take-off roll on runway 09. The pilot of the PA-28, who assumed the Dash 8 was still backtracking, gave a rolling call and also commenced departure At the intersection of runways 09 and 36, the Dash 8 crossed 600m (1,970ft) in front of the PA-28.
The ATSB probe found that during various call-outs the PA-28 pilot misidentified the runway as ‘35’ rather than ’36.’
The inaccurate call-outs occurred as the Dash 8’s crew focused on obtaining pre-departure information from air traffic control (ATC). The volume of their CTAF was also turned down, and an over-transmission from ATC likely meant their understanding of the situation at Mildura was incomplete – owing to airport buildings, the ends of runway 09 and runway 36 are obscured from each other.
As such, the Dash 8 crew believed that the PA-28 was not at Mildura. Moreover, the Dash 8 crew did not give a rolling call-out as this was not a requirement.
The Dash 8 was carrying 33 passengers and three crew, while only the pilot was aboard the PA-28.
Following the incident, QantasLink has updated requirements to add a rolling call at CTAF aerodromes.
In addition, the ATSB is looking into potential radio interference at Mildura owing to a similar incident that occurred on 29 September 2023.
In that case, the pilot of a Lancair (VH-VKP) announced that they were lining up to take off from runway 36, but then had to hold position when the crew of another QantasLink Dash 8 Q300 (VH-TQZ) said they were already taking off on runway 09.
“Situational awareness and alerted see-and-avoid is an effective defence against collisions, and good airmanship dictates that all pilots should be looking out and not be solely reliant on the radio for traffic separation,” says the ATSB.
“Being aware of other nearby aircraft and their operational intentions is important. Remember that there may be a variety of aircraft of different sizes, flight rules, and performance levels all operating at the same time, in the same airspace.”
