Ireland and Britain's air traffic control organisations have jointly agreed the creation of a new flying zone to limit the disruption caused by ash emitted by an Icelandic volcano.
The new "Time Limited Zone" came into operation place over UK and Irish airspace from midday today, allowing airlines to fly through areas of medium ash density that were previously off limits.
The decision followed the grounding of 1,000 flights in parts of northern Europe yesterday because prevailing winds pushed a cloud of volcanic ash from Iceland across parts of the region.
Thousands of Irish air passengers experienced disruption with Dublin one of the worst-affected airports in Europe, with almost 200 flights cancelled yesterday morning, affecting the travel plans of some 17,000 people.
Although Cork and Shannon airports remained open, there were delays and flight cancellations because of closures elsewhere. A complete schedule of flights did, however, resume yesterday afternoon after the Irish Aviation Authority (IAA) lifted restrictions on airspace
Several of Europe's busiest airports, including London's Heathrow and Schiphol in Amsterdam, were also closed for several hours due to fears the ash could damage jet engines and bring down aircraft.
Eurocontrol, the European air traffic agency, said about 1,000 flights out of a total of 28,000 in Europe had been cancelled yesterday, but said the situation was improving.
The volcano, under the Eyjafjallajokull glacier in Iceland, has been erupting for weeks and shows no sign of weakening.
Last month the volcano's ash prompted a number of European countries to close their airspace for nearly a week and travel chaos ensued in Europe and beyond.
British Airways chief executive Willie Walsh said the closure was a "gross over-reaction” to a very minor risk. "It can be managed and we don't need these blanket closures," he told reporters in London.
Iceland's meteorological service said in a statement that the plume of ash was reaching an altitude of seven to nine km and geophysicist Magnus Tumi Gudmundsson of the University of Iceland said the volcano was producing ash unabated.
"Our calculations indicate that when the plume rises up to 6-7 km, the volcano is producing 150-200 tonnes (of ash) per second. When it reaches 8-9 km the production is likelier to be around 400 tonnes per second," he said on state radio. "There are no signs of the eruption slowing down yet," he added.
More than 100,000 flights were cancelled across Europe last month because the volcanic ash formed a cloud over the continent. Millions of people were stranded and airlines, already battered by the global economic downturn, lost $1.7 billion, the International Air Transport Association (Iata) has said.
Iata said today European aviation authorities urgently need to revise their airspace rules to minimise disruption.
"This problem is not going away any time soon. The current European-wide system to decide on airspace closures is not working," said Iata director general Giovanni Bisignani.
"Safety is always our number one priority. But we must make decisions based on facts, not on uncorroborated theoretical models," he said in a statement.
Iata, whose 230 airline members include Lufthansa and Cathay Pacific, called for more robust data collection, improved decision-making and urgency to tackle the problem.
More than 200,000 flights had operated in European airspace identified as having the potential presence of ash but not one had reported the significant presence of ash, as verified by engine inspections after the flight, it said.
Iata said yesterday that international traffic would decline by four per cent in April because of the disruption. It has estimated that a six-day shutdown of European airspace in April cost carriers $1.7 billion in lost revenues.
Before the eruption, Iata had forecast that airlines would lose $2.8 billion this year after losing $9.4 billion in 2009.
Additional reporting: Reuters