United Airlines domestic flights were grounded for 2 hours by computer outage

All of United Airlines’ domestic flights were grounded for more than two hours Sunday night because of a computer outage, the Federal Aviation Administration said.

International flights weren’t affected by the ground stop, which the FAA said was issued at United’s request.

The sources said the flights were grounded due to a problem with the communication system that airplanes use to send information to United operations. Aircraft Communications Addressing and Reporting System, or ACARS, is used to record and transmit a range of information, including departure times, as well as weight and balance, which is used to calculate takeoff speeds.