The recent computer meltdowns at Southwest and Delta, two of the country’s most efficient and financially sound carriers, resulted in thousands of cancelled and delayed flights, disrupting the lives of hundreds of thousands of travelers. And they were just the latest incidents in what has come to seem like a systemic problem.

Why? And what are the airlines’ plans for restoring dependability to the country’s commercial aviation system?

Those are some of the questions posed by Senators Edward Markey (D-Mass.) and Richard Blumenthal (D-Conn.) in letters sent yesterday to the country’s 13 largest airlines.

We are concerned with recent reports indicating that airlines’ IT systems may be susceptible to faltering because of the way they are designed and have been maintained… As operators in this critical transportation industry, it is your responsibility to ensure that your IT systems are both reliable and resilient. Now that four air carriers control approximately 85 percent of domestic capacity, 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.

In addition to chiding the airlines for their failure to invest in their critical systems infrastructure, the Senators raised pointed questions concerning the airlines’ handling of travelers affected by the disruptions. Among them:

• List all IT outages that caused disruptions of one hour or more during the past five years. How many passengers’ flights were delayed or cancelled as a result of those outages?
• How many affected passengers were eligible to be rebooked on other airlines’ flights; and of those, how many were actually rebooked onto a different carrier?
• Does your airline notify passengers when they are eligible to be rebooked on another airline? How are they notified? If not, why not?
• What other compensation or recourse, including but not limited to lodging, food, and reimbursement, does your airline provide consumers in the event of delays and cancellations?

Good questions all. The airlines have until September 16 to provide answers.

Reader Reality Check

What questions would you add to the Senators’?

After 20 years working in the travel industry, and almost that long writing about it, Tim Winship knows a thing or two about travel. Follow him on Twitter @twinship.

This article first appeared on SmarterTravel.com, where Tim is Editor-at-Large.