Brussels Airport’s gradual recovery from the March 22 terrorist attacks took a hit as walkouts by Belgian air-traffic controllers disrupted flights at the hub. The strike began after Belgocontrol management and labor unions reached an agreement to extend the effective working age of traffic controllers to at least 58, Belgium’s air-traffic-control agency said in a statement on Tuesday. The Guild union was behind the walkouts, according to Belgocontrol. The staffing shortage, which also affected operations at Ryanair Holdings Plc’s Belgian base south of Brussels in Charleroi, led Brussels Airport to cancel all takeoffs and landings from about 4:30 p.m. local time on Tuesday before a gradual resumption at about 5:45 p.m. The terminal continued to operate at a reduced rate with about 50 flights canceled Wednesday morning, Brussels Airport said in a statement. “If actions continue, more flight cancellations are to be expected,” it said. Tighter Security Following the terrorist attacks, Brussels Airport currently has a maximum capacity of 225 departing flights per day, about two-thirds of regular traffic in April, as tighter security arrangements have been put in place. The tougher checks and makeshift infrastructure restrict maximum check-in capacity at the airport to 800 passengers per hour. The International Air Transport Association, which represents more than 250 carriers that account for over 80 percent of global air traffic, lashed out at the walkout. “This action by air-traffic controllers is a kick in the teeth for all the airline and airport staff who have worked so hard to reconnect Brussels to the world after the appalling terrorist attack,” IATA Director General Tony Tyler said in an e-mailed statement from Geneva. “It is the height of irresponsibility.”