Tens of thousands of stranded Qantas Airways passengers worldwide scrambled to get to their destinations yesterday after the airline abruptly grounded its global fleet over a dispute with striking workers. Australia’s government sought a court order to force the flagship carrier’s planes back in the air.

Australian officials expressed frustration over the sudden action by the world’s 10th-largest airline and asked an emergency arbitration hearing to order Qantas to fly in Australia’s economic interests.

“It’s not our place to start allocating responsibility, but what I also know is there is a better way to resolve these matters ... than locking your customers out,” Australian Assistant Treasurer Bill Shorten told reporters ahead of the arbitration hearing in the southern city of Melbourne. “We want more common sense than that.”

About 70,000 passengers fly Qantas each day, and they were stuck in airports around the world trying to make alternate arrangements after Qantas announced Saturday that it had grounded all flights until unions reach an agreement with the company.

Qantas already had reduced and rescheduled flights for weeks after union workers struck and refused to work overtime out of worries that a restructuring plan would move some of Qantas’ 35,000 jobs overseas.

German tourist Michael Messmann was trying to find a way home from Singapore on Sunday. He and his wife spent five weeks traveling around Australia but found their connecting flight home to Frankfurt suddenly canceled.

“I don’t know the details of the dispute, but it seems like a severe reaction by the airline to shut down all their flights. That seems a bit extreme,” said Messmann, 68. “After five weeks of traveling, we just want to go home.”

Australian business traveler Graeme Yeatman, however, sided with the airline, even though he was also trying to find a new flight home to Sydney on Sunday after his flight was canceled.

“I think the unions have too much power over Qantas. Even though this is an inconvenience for me, I’m glad the airline is drawing a line in the sand,” said Yeatman, 41.

A court heard testimony Sunday in an emergency arbitration hearing called by the government.

Qantas CEO Alan Joyce said the airline could be flying again within hours if the three arbitration judges rule to permanently terminate the grounding and the unions’ strike action.

The unions want the judges to rule for a suspension so that the strikes can be resumed if their negotiations with the airline fail.

In testimony to the court Sunday, Qantas executive Lyell Strambi said that suspending the staff lockout for three months could endanger aircraft safety.

He said crews could be distracted or angered by the risk to their future earnings of another lockout, which could cause fatigue and degrade personal performance.

“That could lead to conflicts in the cockpit — an array of things,” Strambi told the tribunal.

“Action is suspended for a period of time, but the threat of action doesn’t go away,” Strambi said. “The genie is out of the bottle.”

Planes in the air continued to their destinations when the grounding was announced, and at least one taxiing flight stopped on the runway, a passenger said. Among the stranded passengers are 17 world leaders attending a Commonwealth summit in the western Australian city of Perth.

When the grounding was announced, 36 international and 28 domestic Australian flights were in the air, the airline said.

Qantas said 108 airplanes were being grounded at 22 airports, but did not say how many flights were involved.

The lockout was expected to have little impact in the United States. Only about 1,000 people fly daily between the US and Australia, said aviation consultant Michael Boyd.

Los Angeles International Airport spokeswoman Diana Sanchez said she was not aware of any passengers stranded at the airport because of the strike.

Five Los Angeles-bound Qantas flights were already in the air when the lockout began and arrived as scheduled, she said, but the airline canceled the rest of the weekend’s flights to and from Los Angeles, including six arrivals and six departures on Sunday.

Booked passengers were being rescheduled on a 24-hour basis, with Qantas handling any costs in transferring bookings to other airlines, said Qantas spokesman Tom Woodward.

Bookings already had collapsed after unions warned travelers to fly other airlines through the busy Christmas-New Year period.

Joyce told a news conference in Sydney that the unions’ actions had created a crisis for Qantas.

“They are trashing our strategy and our brand,” the chief executive said. “They are deliberately destabilizing the company, and there is no end in sight.”

Union leaders criticized the action as extreme. Qantas is among the most profitable airlines in the world, but Joyce estimated that the grounding would cost the carrier $20 million a day.

The grounding of the largest of Australia’s four national domestic airlines will take a major economic toll and could disrupt the national Parliament, due to resume in Canberra on Tuesday after a two-week recess. Qantas’ budget subsidiary Jetstar continues to fly.

Prime Minister Julia Gillard said her government would help the Commonwealth leaders fly home after 17 were due to fly out of Perth on Qantas planes over the next couple of days.

“They took it in good spirits when I briefed them about it,” Gillard told reporters.