American Airlines flights were cleared to fly by regulators early Tuesday after a brief grounding due to systemwide technical issue. Just before 7 a.m. Eastern time, the Federal Aviation Administration ordered all American Airlines flights grounded in the U.S. at the airline’s request. American had reported a technical issue affecting its entire system with millions traveling for the holiday. The ground stop, according to the time stamps on the FAA’s orders, lasted exactly one hour. The groundings couldn’t come at a worse time for the millions of travelers expected to fly over the next 10 days.