The FAA has stopped work on dozens of projects and furloughed nearly 1,000 employees after Congress failed to reach an agreement on its budget.
Federal Aviation Administration Chief Randy Babbitt says he has directed controllers at all regional radar facilities to contact the towers of airports where there is only one controller on duty at night before sending planes on for landings.
Babbitt also says regional controllers have been told that if no controller can be raised at the airport, they must offer pilots the option of diverting to another airport.
The incident at Reagan is still being investigated. The air traffic controller who was on duty and asleep in the control tower has been suspended.