U.S. air traffic controllers will be offered the opportunity to stay past their mandatory retirement age of 56, U.S. Transportation Secretary Sean Duffy told Fox News on Thursday in the wake of the Washington plane crash.

They must have two to four years of experience before full certification. Once in the job, the hours are long, and the pay is low until they gain experience.

President Trump says he thinks a more modern air traffic control computer system could have prevented last week’s deadly collision between a passenger jet and Army helicopter.