U.S. airlines were working their way through hundreds of delayed flights Monday after a data disruption temporarily suspended takeoffs across the country.

Southwest Airlines Co. was particularly hard hit, as the carrier voluntarily grounded all its planes for 40 minutes during the technology glitch at AeroData Inc., a provider of aircraft weight and balance information. Delays affected 992 of Southwest’s flights, according to data tracker FlightAware.com, representing about a quarter of the airline’s 4,000 daily flights.

“Because of our size and scope, and combined with our ground stop, it had a pretty big impact to our operation,” said Dan Landson, a Southwest spokesman.

The intermittent problem affected the regional partners of Delta Air Lines Inc. and United Continental Holdings Inc. American Airlines Group Inc. said some of its commuter affiliates were affected.

The interruption lasted for about 48 minutes starting at 5:24 a.m. in Washington, the Federal Aviation Administration said in a statement. The weight and balance information provided by AeroData is needed for flight planning, the agency said. Mainline and regional carriers were affected to varying degrees.

Details of an aircraft’s weight, and how the weight is distributed, are required before a flight can take off. Such calculations also must be approved by airline dispatchers in remote offices, complicating flight schedules if communications or computer systems crash. Calls to AeroData weren’t immediately returned.

United said 150 flights by its United Express regional carriers were delayed.

“Some flights that were affected have departed, and we’re working to get all affected flights back on schedule,” the carrier said in a statement. Delta said it didn’t expect any cancellations among the Delta Connection flights delayed by the outage.