They want to know why the industry’s tech systems haven’t been modernized.

By Christopher Tkaczyk
Updated: January 21, 2017
Chip Somodevilla/Getty Images

Airline tech outages have caused system-wide flight delays and cancelations this summer, stranding thousands of passengers across the U.S.—and Senators Richard Blumenthal (D-Conn.) and Edward Markey (D-Mass.) want to know what the heck is going on.

The senators sent letters to 13 major airlines on Tuesday, expressing concern about the industry's tech failures. They cited last week's Delta Air Lines debacle, which saw some travelers stuck for days, and Southwest's outage in July.

They also want to know why fewer passengers are being re-booked on competing carriers—a practice known as interlining. In recent years, there has been less cooperation between the major carriers, which have also been reducing capacity. Last year, Delta dropped its agreement with American Airlines after the two companies couldn’t agree on a pricing structure.

"Now that four carriers control approximately 85 percent of domestic capacity,"Blumenthal and Markey​ wrote, "all it takes is one airline to experience an outage and thousands of passengers could be stranded, resulting in missed business meetings, graduations, weddings, funerals, and other prepaid events." The letters ask questions about each airline's safeguards and plans for a backup in the event of an outage.

The antiquated IT systems of major U.S. carriers are a result of years of industry consolidation. Airlines have put their resources into integration instead of upgrades, and merging those old, complex systems has created temperamental and increasingly unstable networks. Most airline reservations systems rely on an IBM operating system that was built in the 1960s.

It's incredibly expensive and complicated to replace airline computer systems. Scott Nason, the former CIO of American Airlines Group, says long-term investments in computer technology were a tough sell when he worked there. "Most airlines were on the verge of going out of business for many years, so investment of any kind had to have short pay-back periods," he told Reuters.

Earlier this summer, Markey and Blumenthal wrote to airlines to urge them to stop charging baggage fees, blaming them for causing long delays at airport security lines as more passengers bring carry-on baggage to avoid additional costs. So far none of the airlines have acquiesced.

Christopher Tkaczyk is the Senior News Editor at Travel + Leisure. Follow him on Twitter and Instagram at @ctkaczyk.