WASHINGTON _ A week after a computer failure caused a worldwide service meltdown at Delta Air Lines, two senators have asked all domestic carriers to explain how resilient their information technology systems are.
Sens. Richard Blumenthal of Connecticut and Ed Markey of Massachusetts, Democrats on the Senate Committee on Science, Commerce and Transportation, wrote to 13 airlines to express concern that there aren't enough backups in place to prevent service disruptions like the ones that paralyzed Delta last week and Southwest Airlines last month.
The senators also questioned the airlines on their vulnerability to cyberattacks.
Delta canceled more than 2,100 flights last week, more than it had in the first seven months of the year.
Experts questioned last week why the airlines failed to put adequate backup systems in place. Industry consolidation has turned airline computer systems into a complex jumble.
While the U.S. Department of Transportation and the Department of Homeland Security regulate aviation safety and security, they have very little oversight of airline service.
The senators noted that just four carriers _ Delta, American, United and Southwest _ now control 85 percent of domestic air travel, and a disruption experienced by just one can wreak havoc across the entire aviation network.
"In light of these recent technology issues," they wrote, "we encourage you to ensure that your IT systems have the appropriate safeguards and backups in place to withstand power outages, technological glitches, cyberattacks and other hazards that can adversely affect IT systems."
Blumenthal and Markey also demanded that the airlines offer better rebooking options or compensation to inconvenienced travelers.
"Air carriers should rebook interested passengers on another airline or on a different mode of transportation without charging customers additional costs or fees and should provide passengers with full reimbursement and compensation, including for any needed meals and lodging," they wrote.
Delta did offer passengers delayed more than three hours last week a $200 travel voucher and the ability to rebook flights without the customary change fees. The airline also provided hotel vouchers to passengers who were delayed overnight.
Early Aug. 8, what the airline is calling "a power control module" _ and what a Georgia Power spokesman described as essentially a fuse box _ malfunctioned at the airline's data center in Atlanta, causing a power surge and a loss of power. Backup systems did not work as intended, and the airline was unable to check in and board passengers or dispatch aircraft.
The airline didn't resume normal operations until three days later.
On July 20, a Southwest computer router failed, taking down the company's website and grounding 2,300 flights over four days. Southwest's backup systems also didn't work properly.
Blumenthal and Markey asked the carriers to respond to their questions by Sept. 16.
