ATLANTA (AP) - The Federal Aviation Administration says the problem has been fixed, but for the second time in 15 months, a glitch in its flight plan system has triggered cancellations and delays that are still affecting flights across the nation.

The FAA says the problem began early this morning and involved the system that collects airlines' flight plans. That forced airline dispatchers to send plans to air traffic controllers, who have been entering them manually into the system. The outage also affected traffic management, including ground stops and ground delays.

Hartsfield-Jackson Atlanta International Airport has been particularly affected by today's troubles. Chicago and Washington, D.C., are also reporting delays. Passengers are being asked to check the status of their flights online before going to airports.

The FAA collects flight plans at two centers, one in the Salt Lake City area and the other in the Atlanta area. A software glitch at the Georgia facility in August of last year delayed hundred of flights across the country.