WASHINGTON—Progress toward completing FAA’s NextGen air traffic control (ATC) modernization program is lagging, U.S. Transportation Secretary Elaine Chao told the Aero Club of Washington in a June 13 address. “Since 2007, there have been 39 audits of NextGen implementation by the Transportation Department [DOT] Inspector General, and six are currently ongoing,” said Chao, according to a copy of her prepared remarks. “The system still has not been fully ...