The Federal Aviation Administration needs more funding from Congress to complete phase one of a $10.6 billion air traffic control reform plan and has underestimated the total costs of operating the new system, a government report said Monday.

The Government Accountability Office said the FAA had not fully assessed the costs of operating the new system or set a detailed schedule for completing reforms.

The air traffic control tower at Chicago O'Hare International Airport is pictured on the day passengers board their flights for the Thanksgiving holidays, in Chicago, Illinois, November 26, 2025. REUTERS/Jim Vondruska

"In essence, the FAA is buying delivery speed at the risk of cost uncertainty and potential disruptions," the GAO report said, adding "these risks increase the likelihood of FAA repeating its history of cost overruns, delays, and unmet performance targets."

Congress previously approved $9 billion for ATC reforms in the first phase set to cost $10.6 billion. The FAA is using $1 billion from its current year budget and needs another $574 million, the GAO said.