What happened
On 29 September 2023, a runway conflict occurred at Mildura Airport involving a Lancair, registered VH-VKP, and a QantasLink Dash 8-315, registered VH-TQZ. The Dash 8 was in the process of taking off from runway 09 when it crossed the intersection of runway 36. At the same time, the Lancair was lined up for departure on runway 36. The pilot of the Lancair halted the aircraft on the runway after being alerted to the conflicting traffic by the Dash 8 crew and another aircraft in the vicinity.
The investigation
The investigation examined the breakdown in situational awareness and communication between the two crews. The Dash 8 crew was managing several airborne aircraft during a busy departure phase, which led to a heavy focus on maintaining separation with overhead traffic. This intense focus resulted in a state of inattentual deafness, where the crew failed to perceive the Lancair taxiing on a different runway.
Furthermore, the investigation found that the Lancair pilot's radio call regarding entering and back-tracking on runway 36 was partially lost due to an over-transmission. This prevented other pilots from recognizing the potential hazard. Additionally, the use of the VHF COM 2 radio by the Dash 8 crew for local communications resulted in reduced signal strength and clarity, making it difficult for other airfield users to receive or interpret their transmissions.
Findings
- The Dash 8 crew was preoccupied with coordinating separation for other airborne aircraft, leading to a lack of awareness regarding the Lancair on the ground.
- An over-transmission caused the Lancair's position and intentions to be only partially communicated to the field.
- Radio reception and transmission strength for the Dash 8 was degraded due to the use of the VHF COM 2 radio and geographical shielding from buildings and topography.
- The lack of a requirement for mandatory rolling calls increased the risk of aircraft being unaware of each other immediately before takeoff.
- There was no published guidance from the manufacturer regarding the limitations of the Dash 8 VHF COM 2 radio for ground-based communications.