Delays occurred first in Chicago, New York, Miami and Boston and spread to Dallas, Atlanta, Detroit and Washington, D.C. Southwest Airlines lifted an internal ground stop at 7:05 Eastern that had been implemented for about 40 minutes. Almost 500 Southwest flights were delayed by 7:45 a.m., according to flight tracking website FlightAware. “Southwest Airlines has issued a ground stop this morning as a result of a technology outage involving a vendor that provides aircraft weight and balance data,” the airline said in a statement.
About 150 flights of United Express were also impacted. Delta said that the outage prevented some of its Delta Connection flights from leaving on time. The issue has been resolved. “Earlier this morning, AeroData had a technical issue that impacted a few of our regional carriers,” American spokesman Ross Feinstein said in a statement. “This technical issue has been resolved. We apologize to our customers for the inconvenience.” Passengers complained about the delays on Twitter.