Will Volcanic Ash Stop? Some Flight Restrictions Relaxed as Icelandic Eruption Continues

May 19, 2010— -- Flying to and around Europe these days can seem a bit like spinning a roulette wheel as governments there periodically impose flying bans because of ash from Iceland's Eyjafjallajokul volcano.

On Monday alone, 1,000 flights were canceled mostly in Britain and the Netherlands.

But now, British aviation authorities are loosening their restrictions so that more planes can fly during the eruption.

Just how long the volcano will continue spewing dangerous ash into the skies over Europe is anyone's guess. Scientists monitoring the eruption at Eyjafjallajokul are still detecting dozens of small earthquakes beneath the volcano, suggesting that magma is still building up from deep in the earth and will continue to feed the volcano.

And let's not forget that the last time Eyjafjallajokul erupted, in December 1821, it did not stop for nearly 14 months.

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So with the key summer travel months nearly here, the United Kingdom's Civil Aviation Authority -- facing political pressure and accusations it overreacted -- has decided to change its threshold for what it deems safe conditions for flying.

The CAA created a new "Time Limited Zone" that approved airlines can fly through briefly at higher ash concentrations. The new rules, which went into effect Tuesday, allow flights if there are up to 0.004 grams of ash per cubic meter of air, twice the prior limit.

The British government said it created the new rules after talking with aircraft and engine manufacturers, establishing what level of ash planes can safely handle.

"Unprecedented situations require new measures and the challenge faced should not be underestimated," Andrew Haines, the head of the CAA said in announcing the new rules.

Haines added that the default procedure for aircraft to avoid ash completely "doesn't work in our congested airspace" and that "the world's top scientists tell us that we must not simply assume the effects of this volcano will be the same as others elsewhere."

"Its proximity to the U.K., the length of time it is continuously erupting and the weather patterns are all exceptional features," he said.

New British Ash Cloud Rules

The head of discount airline Flybe said the rules will make a giant difference. On Monday, the airline had to cancel 380 flights because of the ash restrictions. With the new rules in place, Flybe said it would have only had to cancel 21 flights.

"This level of cancellation would be more akin to a weather event and therefore much more bearable for customers and the industry," Flybe CEO Jim French said.

The less-restrictive rules come as a campaign by the airlines against the government regulators intensifies.

The airlines estimate that they have lost $1.7 billion so far since Eyjafjallajokul started erupting April 14. More than 100,000 flights have been cancelled, leaving millions of passengers stranded. Other flights have been delayed by hours, taking costly, out-of-the way routes to avoid the ash cloud.

The International Air Transport Association, which represents 230 airlines accounting for 93 percent of the world's scheduled international air traffic, blasted government authorities Tuesday morning, saying that it was time for governments to revamp their policies and allow more flights.

"This problem is not going away any time soon. The current European-wide system to decide on airspace closures is not working," said Giovanni Bisignani, head of the airline association. "The result is the unnecessary closure of airspace. Safety is always our number-one priority. But we must make decisions based on facts, not on uncorroborated theoretical models."

The steps by Britain yesterday, as well more-lenient policies by the French government, were noted by Bisignani, who called for more testing and data.

More than 200,000 flights have operated in European airspace identified as having the potential presence of ash, the airline association said. But not one of those airplanes has reported significant ash presence, something verified by post-flight aircraft and engine inspections.

"We have lost confidence in the ability of Europe's governments to make effective and consistent decisions. Using the same data, different countries have come to different conclusions on opening or closing airspace," said Bisignani. "Ultimately the industry needs a decision-making process for ash clouds similar to the one used for all other operational disruptions."