Geologists studying the volcano in Iceland that's spewed ash over much of Europe see no sign the eruption is winding down. And prevailing winds are expected to keep carrying it over the same area.
Countries whose airspace has been affected are trying to adjust flight patterns to allow some air travel. Flights remain banned over much of Europe's airspace this weekend because of the cloud of volcanic ash.
It's the worst flight disruption since the attacks of September 11, 2001, and with planes stuck on the ground, it's costing the airline industry $200 million a day.
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The ash problem is choking the international flight schedules at New York City's international airports, causing frustration, desperation, and anger for passengers waiting for any word on when they can get out.
Traveler John Lucas from England said he was "cheesed off" by the situation, but ruminated that "it's actually one of those things, I suppose, in some ways perhaps it's a reality check, because you know, flying, I suppose, is a privilege, isn't it?"
New York City is doing something to help, offering discounted hotel rooms and cheaper transportation to and from the airport for the stranded passengers.
Mayor Michael Bloomberg announced on Friday that 15% discounts are being offered at more than 30 hotels for passengers who aren't able to get hotel vouchers through their airlines.
The delays were causing financial hardships to some travelers. Some had to check out of hotels and sleep in the airports.
"I have been staying in a hotel but have now checked out and do not know what I am going to do - I have limited financial resources here," said Anthony Adeayo, 45, who was due to travel from Britain to Nigeria with British Airways.
Others, desperate to return home or get to meetings, rushed to book a ride on ferries, in rental cars or taxis.
Hundreds of weary British travelers were forced to queue up in France for ferry tickets, and P&O Ferries said it was inundated by thousands of calls from stranded air passengers. Ferry crossings between Britain and Spain, Belgium and the Netherlands were also fully booked, while a Virgin Holidays Cruises phone operator said dozens of people have called in to ask about trans-Atlantic crossings to New York aboard the Queen Mary 2 cruiser.
A British taxi firm said it pocketed a fortune from driving a group of clients hundreds of miles to Switzerland. International trains on the continent beefed up services, and the Eurostar was running eight supplementary trains Sunday.
A Long Way Home
Frustrated European travelers stranded overseas struggled to find alternate routes home Sunday, desperate for information on flights into the continent's few airports not closed by a dangerous cloud of ash from an Icelandic volcano.
Flights into Rome, Athens and Madrid became the new hot ticket at many international airports - but after three days of travel disruptions, the backlog of passengers meant many faced waiting lists of days, even weeks.
"We'll take any flight to Europe," said Dirk Maertens, 52, slumped against a railing at Bangkok's international airport alongside his wife and 16-year-old son.
The Maertens slept on plastic seats at the airport Saturday night after their flight home to Belgium was canceled. They planned to camp out again Sunday on the off-chance that seats on the already-overbooked Thai Airways flight into Rome might open up.
"When there is a flight, you have to be quick - you have to get on it, you can't be too far away," said Claire Maertens, 49, explaining why the family won't leave the airport.
"It's so strange," she said. "One volcano, and the whole of Europe is down."
Modern Europe has never seen such a travel disruption. Millions of passengers have had plans foiled or delayed. Around the world, anxious passengers have told stories of missed weddings, business deals and holidays because of the ominous plume, which could damage airplane engines.
Some carriers, like Australia's Qantas, put passengers up in hotels, but many did not, offering instead only to refund tickets or exchange them for later flights.
Russia's foreign ministry was organizing round-the-clock consular services to arrange 72-hour visas for foreign passengers stuck at Moscow's three airports, Transportation Minister Igor Levitin said in a televised meeting.
While some airlines in Europe resorted to temporarily laying off staff to cope with lost revenue, Asian companies tried to find ways to keep as many flights as possible running.
Thai Airways, which said the disruption was costing it 100 million baht ($3 million) per day, was encouraging passengers whose flights from Bangkok were canceled to travel instead to airports in southern Europe that are still open.
"We are trying to get passengers if they can to travel to Rome, Madrid and Athens because these are the only three destinations still in operation and we don't know long the disruption will last," the company's president, Piyasvasti Amranand, said.
India's Jet Airways rerouted its flights to New York and Toronto via Athens. It was not servicing its routes to London or Brussels, however, according to airline official A.K. Sivanandan.
Qantas said Sunday that it would continue an abbreviated flight schedule on Monday and Tuesday, allowing flights that would normally go from Australia to Europe via Asian cities to run - but only as far as the Asian stops.
The airline, however, warned passengers not to fly to Asia simply to wait for their connecting European flights to open. But about 1,500 Qantas customers were stuck in Singapore, Bangkok and Hong Kong, spokeswoman Emma Kearns said Sunday. Another 400 international customers were stranded in Australia, the majority in Sydney, she said.
Many travelers said the most frustrating part was the lack of information.
In Bangkok, British business manager Chris Coomber stood in a long line at the Emirates airline counter. He and his wife have been stranded in Thailand since Friday, and they've been told the first flight available isn't until April 29.
"It hasn't been handled well by the airlines," said Coomber, 53, a business development manager from Bournemouth, England. He complained the airline had only one computer and staff member at its information counter, while empty check-in stations were still staffed.
"It's a natural phenomenon. There's not much you can do about it," he said of the volcano. "But I feel badly about how it's been organized, the lack of information and the way the airlines have treated the people who can't get back home."
His schoolteacher wife, Barbara, was eager to get back to her class - a substitute will cost her school 250 pounds ($385) a day, she fretted. But she was more understanding of the airport confusion.
"It's never happened before," she said. "So of course, no one knows how to cope."
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