Southwest flights were grounded across America for the second time in four months Tuesday because of a technical problem, according to federal aviation officials and the airline.
This time, it was a firewall failure -- and the stoppage, mercifully, was brief.
The trouble appeared to start around 10:30 a.m., when the FAA tweeted that Southwest had asked it to halt all departing flights. The airline described the problem as technical and acknowledged the ground stop on Twitter.
"We have had to implement a ground stop as a result of intermittent issues that were experienced, and we should hopefully be resuming our operation as soon as possible. I apologize for any inconvenience this may cause, but we'll be here for you if you need any assistance," Southwest tweeted.
A bevy of tweets from frustrated Twitter users followed. Southwest offered its "sincere apologies" to all of them.
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The stoppage lasted about 30 minutes, with the FAA confirming the issue had been resolved shortly after 11 a.m.
Some travelers hardly appeared mollified by the relative brevity of Tuesday's problems compared with the winter ones.
According to Flight Aware, about 30% of Southwest Airlines' more than 1,200 scheduled flights were affected.
An NBC affiliate reporter was among the impacted travelers.
Southwest later explained the technical glitch was a firewall failure that caused "data connection issues."
"Early this morning, a vendor-supplied firewall went down and connection to some operational data was unexpectedly lost," the airline said in a statement. Southwest Teams worked quickly to minimize flight disruptions."
"We ask that travelers use Southwest.com to check flight status or visit a Southwest Airlines Customer Service Agent at the airport for assistance with travel needs," the statement continued. "We appreciate the patience of our Customers and Employees during this morning’s brief disruption."
Tuesday's air travel woes come after another technical glitch caused an epic travel nightmare for thousands upon thousands of travelers across the U.S. over the holiday season. About 70% of scheduled flights were affected in that case. The days-long debacle was the subject of federal hearings and ongoing regulatory inquiry.
Earlier this year, the airline said it had committed to spending more than $1 billion on technology as a response to the system failures that resulted in flight cancellations nationwide.
