A strike by air traffic controllers forced cancellations of more than 60 percent of flights around France and disrupted travel elsewhere in Europe on Wednesday, as workers protested a plan to simplify Europe's patchwork airspace.
More than 2,000 flights were canceled in France as more workers joined the second day of the strike, according to the civil aviation authority. The walkout started Tuesday and is scheduled to end by Thursday.
The umbrella union for air traffic controllers said 11 countries would take part. The biggest walkout was in France, but had a ripple effect on other European countries.
Britain saw delays primarily related to the French strike. The carrier easyJet canceled 66 flights going to France or passing through its airspace.
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Heathrow Airport, Europe's busiest, said that roughly two-thirds of its 66 daily flights to and from France had been canceled.
Air traffic controllers are upset at the airspace streamlining plan in part because it would hand more air traffic services to private companies. They fear the plan will threaten passenger safety and their jobs, and claim the EU is yielding to industry pressure to cut costs.
At the heart of the dispute is the idea of a single European sky consolidating the Continent's hodgepodge air traffic control systems under a sole authority, turning its many scattered air traffic zones into a few regional blocs, opening up bidding on services like weather forecasting and navigation, and easing what European officials say is a looming capacity crunch.
About 27,000 flights a day now cross European airspace, for a total of over 9 million a year and most are flying under air traffic management systems that were designed in the 1950s, the European Commission said.
Air France, in a statement Wednesday, warned passengers to delay all travel on short- or medium-distance flights until Friday or later, "because of a hardening of the labor movement."
It said it is trying to maintain its long-haul flights, and that it hopes to gradually return to normal Thursday.
At Paris' Charles de Gaulle Airport, red "canceled" notices filled information screens Wednesday and stranded passengers crowded on benches to sleep.
Frenchman Denis Irinee spent the day trying to get home to Montpellier in southern France after vacationing in Asia.
"It's a huge mess," he said. "They promised us flights here and there, but they were all canceled one after another, so in theory we will not have any flights to go home to Montpellier today."
—By The Associated Press