DALLAS         -         Southwest Airlines continues to fly airplanes with safety concerns while federal officials do a poor job overseeing the airline, a government watchdog said Tuesday. The airline has flown more than 150,000 flights on 88 jets it bought on the used-plane market and which had unconfirmed maintenance histories, the Transportation Department’s inspector general said in a report. That put more than 17 million passengers at risk, according to the report. In 2017, FAA inspectors began finding “potentially serious gaps” in Southwest’s process for verifying the condition of the planes, including major repairs that weren’t documented and maintenance records that didn’t meet FAA standards. Meeting U.S. standards normally takes up to four weeks per plane, but people hired by Southwest approved 71 of the planes on the same day, the inspector general said. Southwest said 80 of the planes have been inspected and returned to flying, and the last eight are undergoing maintenance. The FAA gave the airline until this summer to bring the planes in compliance with federal rules because it accepted Southwest’s argument that the issues were low safety risks, the inspector general said. The watchdog office added that FAA has not given its inspectors enough guidance on reviewing risk assessments and evaluating an airline’s safety culture. “As a result, FAA cannot provide assurance that the carrier operates at the highest degree of safety in the public’s interest, as required by law,” the inspector general said.

That is so even though “FAA representatives — ranging from senior executives to local inspectors — expressed concerns about the safety culture at Southwest Airlines.”

Southwest said it has taken steps to address the report’s key findings, and it “adamantly” disagreed with the critique of its safety culture.

“Southwest maintains a culture of compliance, recognizing the safety of our operation as the most important thing we do,” airline spokeswoman Brandy King said in a statement. The airline works “to improve each and every day, any implication that we would tolerate a relaxing of standards is absolutely unfounded.”

The report is another setback for the FAA, which is being investigated by Congress for its approval of the Boeing 737 Max, the plane that was grounded after two crashes killed 346 people. Critics have said the agency is too cozy with airlines and aircraft manufacturers.