Australia's transport ministry will establish an independent panel to examine operational challenges at Airservices Australia, the state-owned air traffic services provider, after the Australian Transport Safety Bureau (ATSB) opened investigations into four near-miss incidents at Sydney airport in July and August.

Preliminary ATSB reports into the four events — a mix of runway incursions and taxiing proximity occurrences at the country's main international gateway — identify air traffic controller staffing in Sydney Tower as a recurring line of enquiry, though the bureau has not determined whether resourcing directly contributed to any of the incidents.

The panel will "ensure Airservices is taking practical and timely action to address challenges including air traffic control workforce planning, recruitment, training, roster resilience and system improvements," the transport ministry states. It will also "provide independent assurance" that the agency is implementing "timely, enduring measures" to improve its services.

What do the preliminary reports show?

ATSB chief commissioner Angus Mitchell says the bureau is examining air traffic control involvement in each of the four incidents.

"Staff resourcing within Sydney Tower at the time of many of the occurrences has emerged as a recurring area of enquiry," Mitchell says.

The preliminary reports also note that Airservices Australia's own roster modelling predicted elevated fatigue risks for staff at the time of many of the occurrences. The ATSB "has yet to determine" whether staffing levels directly contributed to the events.

"We are examining the effectiveness of the measures in place to manage this identified risk," Mitchell states.

The investigations will scrutinise specific rostering practices, he adds:

• the combining of operational roles within the tower;
• routine reliance on overtime to fill shifts;
• training or supervision activities conducted alongside operational duties.

Which incidents are under investigation?

The four occurrences took place between late July and mid-August and involved some of the country's largest carriers.

On 27 July, a Qantas Boeing 737-800 was involved in a runway incursion after it was cleared to cross ahead of a QantasLink De Havilland Canada Dash 8 during the latter's landing roll.

Two incidents occurred on 9 August. The first was another runway incursion, involving a Qantas 737 and a Virgin Australia 737. The second, a "taxiing proximity event," saw a Jetstar Airbus A320 brake "abruptly" to avoid a Qatar Airways Boeing 777-300ER being towed. A Jetstar flight attendant fractured a wrist after falling during the braking — the only reported injury across the four events.

The fourth incident, on 18 August, involved two Qantas aircraft: an A321 freighter that had to brake to allow a 737 to pass in front of it.

What comes next?

The independent panel's review of workforce planning, roster resilience and system improvements at Airservices Australia will run alongside the ATSB's continuing investigations, with the bureau yet to establish whether the staffing pressures it has identified were causal — a question the final reports are expected to answer.