UPDATE: (CNN) -- American Airlines' computer systems are back online, but the carrier expects more flight delays and cancelations for the rest of Tuesday, American Airlines said in a written statement.
American Airlines has instituted a "system-wide ground delay" until 5 p.m. ET, the airline tweeted Tuesday.
Earlier, the airline reported a problem with its reservation and booking tool, noting the network was experiencing "intermittent outages."
American estimates it flies about 275,000 passengers a day and receives more than 239,000 reservations calls.
CNN's Devon Sayers contributed to this report.
Copyright 2013 Scripps Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
One person will win a three-year lease on a 2013 Honda Civic Lx Sedan automatic.
Click to see the latest mugshots, plus this week's wanted fugitives.
This feature packed upgrade brings you faster performance, easier navigation, and stunning improvements to photos, video and readability.
Latest Money Headlines
After a Consumer Watchdog investigation, the Department of Transportation took action against a Pompano Beach moving company.