France halves flight schedules on air traffic control strike

France’s civil aviation authority told airlines to halve flight schedules on Friday due to a planned strike by air-traffic controllers, bringing disruption back to the country’s airports after a difficult summer.

The DGAC’s guidance came in response to a walkout called for Sept. 16 by the SNCTA union, the authority said in an emailed statement Tuesday. Minimum service rules will be in place where applicable, it said.

In spite of the preventive measures, “flight cancellations and significant delays are to be expected” everywhere in French territory, DGAC said. “Passengers who can are invited to postpone their trips,” it said.

Air France-KLM shares slumped as much as 5.6% in Paris, extending declines after the strike announcement, and traded 4.1% lower at the close. 

Airlines were forced to scrap thousands of flights this summer as airports shrank schedules in response to a staffing crisis, with the situation exacerbated by strikes among pilots, cabin crew, baggage handlers and others pressing for higher pay. Hubs in cities across Europe including London, Amsterdam and Frankfurt were among those suffering from the disruption.

DGAC said it’s working with Eurocontrol to offer alternative flight paths for airlines on Friday.