American Airlines flights were cleared to fly by regulators early Tuesday after a brief grounding due to a 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. In social media replies to frustrated travelers, the airline said: “Our team is currently working to rectify this. Your continued patience is appreciated.” The company has not issued a press release explaining the issue and an email was not immediately