Travel chaos not over yet
Paisley Dodds and Danica Kirka
London - Many European flights took to the skies on Tuesday for the first time in days but the travel chaos was far from over: London's airports remained shut, a massive flight backlog was growing and scientists feared that history could repeat itself with yet another volcanic eruption in Iceland.
London's airports - among the busiest in Europe and a major worldwide hub - are likely to stay closed until Wednesday, and forecasters said more delays were possible if the dense ash cloud remained over much of the country.
Airspace in Germany also remained officially closed until 18:00 GMT but a limited number of flights were allowed in at low altitude.
But it was the first day since Wednesday's eruption of Iceland's Eyjafjallajokull volcano - dormant for nearly 200 years - that travellers were given a glimmer of hope.
Cheers and applause erupted as flights took off from Paris' Charles de Gaulle Airport, Amsterdam and elsewhere.
"Everyone was screaming in the airplane from happiness," said Savvas Toumarides of Cyprus, who finally arrived in New York after getting stuck in Amsterdam for five days and missing his sister's wedding.
He said the worst part was "waiting and waiting and not knowing".
Normal by Friday
"We were in the hotel having breakfast, and we heard an aircraft take off. Everybody got up and applauded," said Bob Basso of San Diego, who has been staying near Charles de Gaulle since his flight Friday was cancelled. "There's hope."
Basso, 81, and his son had tickets for a flight to Los Angeles later on Tuesday (today).
The Eurocontrol air traffic agency in Brussels said it expected a little over half - 53% - of the 27 500 flights over Europe to go ahead Tuesday, a marked improvement over the last few days. The agency predicted close to normal takeoffs by Friday.
"The situation today is much improved," said Brian Flynn, deputy head of operations at the Brussels-based agency.
But with more than 95 000 flights cancelled in the last week alone, airlines faced the enormous task of working through the backlog to get passengers where they want to go - a challenge that could take days or even weeks.
Passengers with current tickets were being given priority - stranded passengers were being told to either pay for a new ticket, take the first available flight or to use their old ticket and wait for days, or weeks, for the first available seat.
"I'm supposed to be home, my children are supposed to be in school," said Belgian Marie-Laurence Gregoire, 41, who was travelling in Japan with her husband and three children, ages 6, 8, 10.
They said the best that British Airways could do was put them on a flight to Rome.
Trigger larger eruption
"I'm tired. I just want to go home," she said.
Although seismic activity at the volcano had increased, the ash plume appeared to be shrinking. Still, scientists were worried that the eruption could trigger an even larger eruption at the nearby Katla volcano, which sits on the massive Myrdalsjokull icecap and has erupted every 80 or so years.
Its last major eruption was in 1918.
Magnus Tumi Gudmundsson, geophysicist at the University of Iceland, said there was circumstantial evidence that an eruption could occur within the next 18 months at the nearby Katla volcano.
"We can of course expect similar (travel) disruption with the Katla eruption," he said. "But it all depends on prevailing winds."
Of the eight eruptions in the last 40 years, only the recent eruption at Eyjafjallajokull was followed by winds blowing southeast toward northern Europe.
An international pilots group warned of continued danger because of the ash, which drifted over the North Sea and was being pushed back over Britain on Tuesday by shifty north winds.
Shaking in the belly
The volcano is also grumbling - tremors, which geologists believe to be caused by magma rising through the crust, can be heard and felt as far as 25km from the crater.
"It's like a shaking in the belly. People in the area are disturbed by this," said Kristin Vogfjord, geologist at the Icelandic Met Office.
A Eurocontrol volcanic ash map on Tuesday listed the airspace between Iceland and Britain and Ireland as a no-fly zone, along with much of the Baltic Sea and surrounding area. The ash cloud also spread westward from Iceland, toward Greenland and Canada's eastern coastline.
Still, planes were being allowed to fly above 7 000m in the United Kingdom.
Flights resumed in Scotland, but only for a handful of domestic flights. Switzerland also re-opened its airspace. Some flights took off from Asia to southern Europe and planes ferried people to Europe from Cairo, where at least 17 000 people were stranded.
Airports in central Europe and Scandinavia have re-opened, and most of southern Europe remained clear, with Spain volunteering to be an emergency hub for overseas travellers trying to get home.
Spain piled on extra buses, trains and ferries to handle an expected rush of passengers.
Britain sent navy ships to Spain and France to fetch 500 troops coming home from Afghanistan and hundreds of passengers who had been stranded by the chaos.
The trip on the HMS Albion, a 173m long amphibious assault ship, will take 40 hours from Santander in northern Spain to Portsmouth, England.
Patricia Quirke of Manchester said she and nine other families drove all night across Spain to catch the Royal Navy ride.
Many Asian airports and airlines remained cautious, and most flights to and from Europe remained cancelled.
Patrizia Zotti, from Lecce, Italy, carried her 6-month-old son on her back as she waited to finally board a flight out of Tokyo on Tuesday. While happy about getting airborne at last, she was concerned about the ash.
"I've read that the exploratory flights were safe, but I'm still a bit worried," she said.Qantas cancelled
Australia's Qantas cancelled its Wednesday and Thursday flights from Asia to Frankfurt and London, as well as return flights to Asia, saying the situation was too uncertain to resume flights into Europe.
Not everyone who wanted to could get on a flight on Tuesday.
Phil Livingstone, a university student from St Helens, England spent three nights sleeping on chairs at Seoul's Incheon International Airport and living off noodles and the one meal a day authorities provided.
"Hope is high at the minute just because it's the only thing we've got," he said.
The aviation industry - facing losses of more than $1bn - has sharply criticised European governments' handling of the disruption that grounded thousands of flights on the continent.
But Gideon Ewers, spokesperson for a London-based pilots group, says historical evidence of the effects of volcanic ash demonstrates that it presents a very real threat to flight safety.
Ash and grit from volcanic eruptions can sabotage a plane, stalling engines, blocking fuel nozzles and plugging the tubes that sense airspeed.