FRANKFURT AM MAIN, GERMANY – FEBRUARY 17: An Airbus A-380 of Singapore Airlines is pictured at Frankfurt International Airport on February 17, 2012 in Frankfurt am Main, Germany. The GdF union (German Gewerkschaft der Flugsicherung), which represents air traffic control employees, says workers overseeing operations on the tarmac at Germany’s busiest airport will walk off the job from 3 p.m. on Thursday, and from 8 a.m. to 10 p.m. on Friday. GdF is engaged in a dispute with airport operator Fraport over pay and working conditions for some 200 ground workers. (Photo by Ralph Orlowski/Getty Images)