European airports made tentative steps toward resuming flights on Tuesday after five days cut off from global air traffic by a huge ash cloud, but much airspace stayed closed after reports of a new plume.
Italy, Switzerland and France reopened their airports early on Tuesday though many flights remained cancelled and in Italy only a handful took off, mainly for domestic destinations. Hungary opened its airspace completely, effective immediately.
But Britain's National Air Traffic Service, which controls UK airspace, said much of Britain's airspace would remain closed to flights below 20,000 feet (6,000 metres) until 1800 GMT at the earliest after air traffic controllers warned a new ash cloud from Iceland's volcano was headed for major air routes.
It said it would make another statement around 1400 GMT.
Poland, which had reopened four airports on Monday, closed them again on Tuesday, as well as shutting the northern part of its airspace to transit flights.
A handful of flights took off from Scottish airports after the restrictions were eased at 0600 GMT. However, a Glasgow airport spokesman said it would close from 1200 GMT until further notice because of the spreading ash cloud.
"It's really just Scottish domestic flights, maybe a couple of international ones, there's one going to Iceland -- yes, it's ironic, isn't it?" said Glasgow airport information officer Steven Boyle.
Germany said it would mostly maintain its no-fly zone until 1800 GMT.
The European Union announced on Monday its members had reached a deal to cut the size of the no-fly zone from 0600 GMT on Tuesday under pressure from frustrated airlines losing an estimated $250 million a day.
But exactly how national authorities would split European airspace into areas where aircraft could fly or not was not clear, and many countries were adopting a cautious approach.
Britain's NATS said in an overnight statement that the volcano eruption was strengthening and a new ash cloud was spreading south and east towards Britain.
"This demonstrates the dynamic and rapidly changing conditions in which we are working," it said.
The meteorological office in Iceland said the volcano, though erupting steadily, was actually emitting less ash and more lava than previously, creating a lower cloud of ash.
Meteorologist Bjorn Einarsson said the emission of more lava meant the volcano, erupting under the Eyjafjallajokull glacier about 120 km (75 miles) southeast of the capital Reykjavik, was producing less ash.
"The tremors in the volcano have been slightly increasing, but that does not give any indication of the amount of the ash cloud. It has changed into a lava producing eruption," he told Reuters.
"The ash cloud is much less because you do not have the water to mix with it. You can still have a lot of tremors going around the volcano because the lava is coming out," he added.
He said the existence of a new plume might be due to the time it took for the cloud to travel from the north Atlantic island to other areas.
"Ash that came up yesterday might be arriving today," he said.
Under the EU deal, flights may be permitted in areas with a lower concentration of ash, subject to local assessments and scientific advice.
Airlines had declared numerous test flights problem-free over the past days, but experts disagree over how to measure the ash and who should decide it is safe to fly. A British Airways jet lost power in all four engines after flying through an ash cloud above the Indian Ocean in 1982.
Eurocontrol said it expected up to 9,000 flights to have operated in Europe on Monday, a third of normal volume.
IATA officials said the economic impact on aviation was greater than after the Sept. 11, 2001 attacks on the United States.
Industry losses worldwide for passenger airlines and cargo companies could reach as much as $3 billion from the cloud, Helane Becker, an analyst with Jesup & Lamont Securities, told Reuters Insider on Monday. For U.S. airlines, she estimated the impact at $400 million to $600 million.
Firms dependent on fast air freight were feeling the strain.
South Korea's Incheon International Airport, the world's fourth-busiest cargo handler in 2008, suffered 3,216 tonnes of lost shipments to Europe from April 16-19, the country's customs agency said.
Twenty inbound and 25 outbound cargo flights had been cancelled. Among those suffering were computer chip and electronics suppliers such as Samsung Electronics and Hynix Semiconductor.
Kenya's flower exporters, which account for a third of EU imports, said they were losing up to $2 million a day.
Thousands of people stranded in Asia were offered a glimmer of hope on Tuesday after the first flights started to take off. A Lufthansa aircraft left Beijing around noon local time (0400 GMT) bound for Frankfurt, the first flight to northern Europe to leave China since late last week.
At least five more flights, bound for London, Paris, Rome and Munich, operated by British Airways, Lufthansa and Air China, were scheduled to leave later in the day.
Millions of people have had travel disrupted or been stranded and forced to make long, expensive attempts to reach home by road, rail and sea, as well as missing days at work and school at the end of the busy Easter holiday season.
Some said they made the best of an unfortunate situation.
"There are much worse places than that to be stuck so we had a pretty good time," said a visitor to Paris from New York who only gave his name as Gabriel. He arrived last Tuesday and was supposed to fly back to New York on Friday.
British businessman Chris Thomas, trying to get home from Los Angeles since Thursday, flew to Mexico City and then aimed to fly to Madrid and spend $2,000 to rent a car for the 14-hour drive to Paris. He was booked on the Eurostar Channel tunnel train to London, and then planned to drive four hours to Wales.
"It's all a bit crazy but you have to err on the side of caution," Thomas said. "Nobody wants to be on the first plane to go down in a volcanic cloud."
Businesses have had to find alternative ways of operating. Communications provider Cisco Systems said companies were turning to videoconferencing to connect executives.
Britain was deploying three navy ships, including an aircraft carrier, to bring its citizens home from continental Europe. The British travel agents' association ABTA estimated 150,000 Britons were stranded abroad. Washington said it was trying to help 40,000 Americans stuck in Britain.
Related news reports:Last Mod: 21 Nisan 2010, 13:04