Congress last year awarded $12.5 billion towards modernizing the aging ATC system. More is needed for software updates, said Secretary Sean Duffy. WASHINGTON, April 21 (Reuters) - U.S. Transportation Secretary Sean Duffy said he was seeking $10 billion from Congress for the next phase of a massive effort to modernize America’s aging air traffic control system and reduce systemic flight disruptions. Last year, Congress awarded $12.5 billion for the project to replace outdated technology and