A newspaper investigation has found that Allegiant Air's planes are four times as likely to break down in flight as those operated by other major U.S. airlines.
The Tampa Bay Times report published Wednesday said Las Vegas-based Allegiant's jets were forced to make unexpected landings at least 77 times in 2015 for serious mechanical failures.
None of the incidents prompted enforcement action from the Federal Aviation Administration, which doesn't compare airline breakdown records to look for warning signs.
Times reporters built a database of more than 65,000 records from the FAA.
The newspaper reports that during interviews at the company's Las Vegas headquarters, Allegiant acknowledged that its planes break down too often and said the company is changing the way it operates.