Air traffic control staffing shortages have sparked widespread disruptions at several major airports around the country.
Sydney, Melbourne and Perth airports have all been impacted, with Airservices Australia issuing an urgent alert on Tuesday morning to warn travellers to expect delays of up to an hour.
More than one quarter of all flights in and out of the three airports are impacted, with ground delays expected to continue throughout the day in Melbourne, while restrictions at Sydney Airport are due to lift at 2pm.
Sydney Airport has also been battered by strong winds, with 40km/h wind gusts forcing Qantas to already cancel at least three flights.
'Strong winds are affecting operations at Sydney Airport and flight delays are expected throughout the day,' Airservices Australia said.
One passenger told Daily Mail it was 'frustrating' after their flight to Canberra was delayed 'twice'.
'The airport needs to step up their game and sort this out - this is not good enough,' they said.
Passengers are urged to check their flight status before heading to the airport.
Passengers face major delays at Sydney and Melbourne airports after air traffic control staffing shortages caused widespread disruption
Ground delays are expected to continue throughout the day in Melbourne and Sydney
'We thank passengers for their patience and understanding,' Airservices Australia said.
The delays come amid growing safety concerns at Sydney Airport after a crew member was injured in the second tarmac near-miss in as many weeks.
Two employees were stood down for mandatory testing after a Jetstar flight departing Sydney Airport for the Gold Coast almost collided with a Qatar Airways plane on Sunday morning.
The Australian Transport Safety Bureau has launched a formal investigation into the incident, while Airservices Australia chief executive Rob Sharp was summoned to Canberra for emergency talks with the federal government.
He apologised for the series of flight delays at Sydney Airport in recent days.
'I want to assure the public that safety is not compromised when issues with staffing levels occur,' Sharp said.
'We put in place measures that reduce the traffic levels to ensure safety, but this can lead to flight delays.'
He added that recruitment of air traffic controllers is tracking well, despite warnings of widespread shortages.
Jetstar and Qatar planes were involved in a near-miss while taxiing on the runway at Sydney Airport on Sunday morning
'However we understand that any delay has an impact on passengers and we are committed to making further improvements, particularly in Sydney,' Mr Sharp said.
'While concerted recruitment efforts in recent years have enabled us to grow air traffic controller numbers to a record high, the demands on our workforce have also grown significantly.'
Federal Transport Minister Catherine King was confident Airservices would adopt the necessary changes.
'We've had a very constructive discussion about measures they are putting in place to ensure there is better rostering at Sydney Airport,' she said.
'What happened over the weekend, they accept, was unacceptable for passengers in particular.'
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