American Airlines flights are departing again after a brief IT outage led to a nationwide ground stop, according to the airline and federal officials.

American Airlines flights not in the air were being held because of an IT outage, according to an advisory from the Federal Aviation Administration.

A “technology issue briefly impacted connectivity” for some systems, the airline said in a statement. “Connectivity has been fully restored. We apologize to our customers for the inconvenience. We appreciate the efforts of our team to bring our systems back online so quickly and take care of our customers.”

Overall, the ground stop lasted about 45 minutes.