Stranded British passengers are waiting to find out if emergency talks would end their misery, after an industrial dispute left hundreds of flights grounded.
Australia's government ordered the arbitration hearing after Qantas Airways grounded its global fleet amid a dispute with striking staff.
Prime minister Julia Gillard said her centre-left government had "taken a rare decision" to seek an end to the strike action out of necessity.
She said: "I believe it is warranted in the circumstances we now face with Qantas ... circumstances with this industrial dispute that could have implications for our national economy."
Qantas chief executive Alan Joyce said the planes could be flying again within hours if the three arbitration judges ruled to permanently terminate the grounding and the unions' strike action.
The unions want the judges to order a suspension so the strikes can be resumed if their negotiations with the national carrier fail.
On Saturday a Qantas spokesman said 600 flights had been cancelled because of the industrial action - affecting 70,000 passengers.
The strikes have cost the airline 15 million Australian dollars (£10 million) a week.
Chris Crulley, 25, from Newcastle, was on a plane taxiing on the runway at Sydney when the pilot told passengers that he had to return to the terminal to "take an important phone call".
"We're all set for the flight and settled in and the next thing - I'm stunned. We're getting back off the plane," the firefighter said from Sydney Airport.