Originally Published: 26 JUL 22 06:00 ET

Updated: 26 JUL 22 06:31 ET

By Matt Egan, CNN

(CNN) -- Air travel is a mess right now and Sen. Elizabeth Warren is demanding that federal regulators do something about it.

In a letter obtained first by CNN, the Massachusetts Democrat, along with California Democratic Sen. Alex Padilla, urges Transportation Secretary Pete Buttigieg to use his vast powers to protect consumers by cracking down on the airline industry. The lawmakers want the Transportation Department to "aggressively" use its authority to hold airlines accountable for surging prices, mounting cancellations and growing delays.

And they not-so-subtly point out that the recent travel chaos comes barely two years after Uncle Sam bailed out the airline industry during the Covid-19 crisis.

"After receiving tens of billions of dollars in assistance from American taxpayers," Warren and Padilla wrote in the letter sent Monday evening, "major airlines have reciprocated by dramatically increasing ticket prices and reaching new lows in their treatment of travelers."

Airlines have blamed a surge of flight cancellations on staff shortages -- including a shortage of pilots -- in the industry. Travel has also been hampered by bad weather, with more than 1,300 flights canceled on Monday alone as East Coast storms disrupted the aviation system, according to FlightAware.

Warren and Padilla urged the Transportation Department to hold airlines accountable for canceling flights, "whether due to their own poor operations and staffing practices or through intentional schemes to offer flights they know they can't staff in order to later cancel the least-profitable flights." They note that 41% of flights are delayed for reasons within airlines' control and called on the agency to issue a rule that imposes fines on airlines for the delays they cause.

"Consistently delaying flights for reasons within an airline's control is an unfair and deceptive practice," the joint letter states.

In a statement, a Transportation spokesperson said the department will continue to pressure airlines over consumer protections.

"The Department expects that when Americans buy an airline ticket, they'll get to where they need to go safely, affordably and reliably," the spokesperson said.

Airlines for America, an industry trade group, cited conditions experienced by the Covid-19 pandemic and said the industry is struggling at a time when travelers are returning to flying "at unexpectedly rapid rates."

The lawmakers took particular issue with intentional rebookings where airlines purposely oversell flights, calling for the Transportation Department to end the practice by forcing airlines to pay a "hefty fine" in addition to compensating passengers.

"When this gamble fails, it should be airlines -- not consumers -- that pay the price," Warren and Padilla write.

The Transportation Department, they note, is empowered to act as a "consumer protection watchdog," citing federal law that allows the agency to investigate unfair or deceptive practices and issue fines of up to $37,377 per violation.

Beyond penalizing airlines for flight cancellations, Warren and Padilla want regulators to stop the decades-long consolidation of the airline industry.

They urge the Transportation Department to "use its full statutory authority more vigorously" to halt "excessive consolidation," which they blame for "consistent" price hikes on consumers.

In the latest example of the shrinking number of airlines in America, low-cost carrier Spirit Airlines is in the center of a bidding war, fielding buyout offers from rivals JetBlue and Frontier Airlines.

"Decades of deregulation and consolidation have created an airline industry that routinely heaps inconvenience and abuse on consumers," the lawmakers write.