British Airways (BAB) said Friday that all of its striking Heathrow Airport (search) workers were returning to work after a 24-hour walkout that saw all flights canceled at the airport and about 70,000 travelers stranded.
The airline said it would operate "a limited number of aircraft" starting at 8 p.m. London time.
But it warned that the disruption caused by more than 500 canceled flights at one of the world's busiest airports would continue for many hours.
"We face a complex logistical challenge with at least 100 aircraft and 1,000 flying crew out of position," said BA's customer services director, Mike Street. "As a result it will take some time to return to a normal flying program."
About 1,000 baggage handlers and other ground staff walked out Thursday in support of workers fired by catering firm Gate Gourmet (search). Analysts warned the airline faced losses of tens of millions of dollars.
About 1,000 passengers spent the night on floors and in seating areas at the airport, BA said, while about 4,000 had been put up in hotels nearby. Incoming flights were diverted to airports as far away as Newcastle in northern England and Glasgow, Scotland.
BA Chief Executive Rod Eddington (search) said the situation was "regrettable in the extreme."
"This is not our dispute," Eddington said. "Our customers must come first and everyone involved in creating this chaotic situation must come to their senses."
But many of the passengers who spent the night on floors and lounge benches, and faced hours-long lines to make alternative flight arrangements, blamed the airline.
"I'm too polite a lady to say what I think of British Airways," said Daphne Morley, a resident of Melbourne, Australia, attempting to fly to St. Petersburg, Russia. "Our luggage is somewhere in Neverland. There's no chance of change of clothing or anything."
Others took it all in stride. A group of Portuguese Boy Scouts fashioned a makeshift shelter out of luggage trolleys and sleeping bags inside Heathrow's Terminal 1.
"We are all a little frustrated, but we can't do anything about it so we don't let it bother us," said Jimmy Kakoo, one of the Scouts.
Qantas, Finnair, British Mediterranean and Sri Lankan Airlines, all of which use BA ground staff, also canceled their flights from Heathrow on Friday.
Heathrow management warned that the disruption would last for days.
"People are saying we won't get out of here until Monday or Tuesday," said Sally Hater, a resident of Cambridge, Vt., who was trying to get a flight to Boston. "We had to wait four hours last night just to get hotel accommodation. They gave us phone numbers, but you can't reach them. They're useless."
Police with submachine guns patrolled the airport as usual. The Metropolitan Police (search) said the strike had led to an escalation of security at Heathrow. A spokeswoman said the force was prepared to send in more officers to keep the peace if passengers became unruly.
There was a ripple effect around the world, as passengers due to fly to London found themselves stuck.
"We've been here for three hours, and no one has said anything about hospitality, or sorry," said Rick Doehring, due to fly to London from Paris' Charles de Gaulle airport (search) en route to Detroit. "It is getting tiring."
The chaos grew from a dispute between catering workers and Gate Gourmet, which provides onboard meals for British Airways flights. The workers' union said the company had fired 800 workers on Wednesday after an unofficial strike. The company said 667 workers had been dismissed.
BA baggage handlers and loaders represented by the same union as the catering staff — the Transport and General Workers Union (search) — stopped work in sympathy with their colleagues.
Some Gate Gourmet staff were astounded at the scale of disruption.
"I didn't expect the BA staff to join us, but we are very happy about it," said Gary Mullins, 37, a loader for the company.
"We don't wish to cause them any more [aggravation] than we have to," he said of the passengers. "But it's something that has to be done."
Gate Gourmet, which is undertaking restructuring amid financial losses, said it was trying to resolve the dispute.
The caterer, which is owned by the Fort Worth, Texas, buyout firm Texas Pacific Group (search), reported a loss of $41.25 million last financial year, and was expecting a $44.84 million loss for the current year.
This is the third consecutive year that BA has suffered a disruption at the height of the summer holiday season. Last August, thousands of disgruntled vacationers were stranded at Heathrow after the airline canceled scores of flights because of staff shortages and technical hitches.
In July 2003, an unofficial walkout by several hundred check-in staff disrupted thousands of passengers and cost BA tens of millions of dollars.
Henk Potts, an analyst at Barclays Stockbrokers, said the latest dispute could cost the airline 10 million pounds ($18 million) a day.
In its last financial year, which ended in March, British Airways PLC earned 251 million pounds ($467.31 million), up from 130 million pounds in the previous year. Full-year revenue rose 3.3 percent to 7.8 billion pounds ($14.49 billion).
BA's U.S. shares fell 34 cents to $52.49 in afternoon trading on the New York Stock Exchange.