Two Democratic senators are pressing airlines to do more to help passengers who get stuck as a result of computer breakdowns like those experienced by Delta and Southwest in recent weeks.

“We believe that, in the event of flight delays and cancellations caused by airlines, airlines should rebook interested passengers on another airline or on a different mode of transportation without charging consumers additional costs or fees and should provide passengers with full reimbursement and compensation,” Sens. Edward J. Markey of Massachusetts and Richard Blumenthal of Connecticut wrote to 13 major airlines Tuesday.

The letter includes a request for information to be provided within a month about information technology issues that have caused flight delays and cancellations, as well as the needed redundancies in place to curtail outages in the future.

“Transparency is critical, and when delays and cancellations are caused by the air carrier, customers should be eligible for a full refund and should be informed immediately of their availability,” Markey and Blumenthal wrote.

[Congress Responsible for Long Airport Lines]

A Southwest Airlines systems outage stranded passengers across the country last month. The airline was not eager to provide alternate forms of transportation. In that case, the carrier said that refunds that could be claimed for up to one year would be offered, even on nonrefundable tickets.

Delta was the most recent airline to experience significant disruptions caused by a power outage.

‎”Airlines are reaping record profits while neglecting major system weaknesses, and passengers are stuck paying the price,” Blumenthal said in a statement. “Airlines are still relying on software from the 1960s — outdated and inadequate technology prone to glitches and meltdowns that have paralyzed air travel and disrupted our global economy.”

The airlines, he said, “must invest now in 21st-century technology and commit to transparent and fair consumer protections in the event of any future breakdowns.”