Congress has left for the week without reauthorizing the Federal Aviation Administration's budget.
That means furloughs and on-going airport projects will be halted.
Specifically, the FAA says:
-- 4,000 FAA employees in 35 states, the District of Columbia, and Puerto Rico will be furloughed
-- air-traffic-control operations will NOT be affected, but engineers, scientists, analysts, office staff, etc. will be affected
-- it will not be able to collect taxes, according to the airlines.
"I'm very disappointed that Congress adjourned today without passing a clean extension of the FAA bill," Transportation Secretary Ray LaHood said in a statement. "Because of their inaction, states and airports won't be able to work on their construction projects, and too many people will have to go without a paycheck. This is no way to run the best aviation system in the world."
Earlier this week, NBC's Luke Russert explained why Congress was unable to pass an extension to keep the entire FAA open.