A strike by French air traffic controllers Thursday over the EU\'s proposed plans to centralize control of European air traffic forced airlines to cancel dozens of flights. The French Directorate General for Civil Aviation, DGAC, said today that the strike would impact flights within France, Spain, Portugal and North Africa. Other flights travelling through French airspace might not be affected, the directorate general added. As a result, DGAG asked airlines to cancel roughly 10% of the day\'s lights. Ryanair alone has cancelled 87 flights. The strike is the second since June by unions protesting the European Union\'s Single European Sky initiative. The largest union USAC-CGT did not join in the action, which was called by two smaller unions, limiting the impact. The EU said centralizing the continent\'s airspace will reduce congestion and inefficiencies that cost airlines and passengers an estimated $6.6 billion a year.