A proposal to reduce the number of hours needed to become a co-pilot was rejected by the FAA.
Republic Airways, which flies short routes for Delta, American and United, proposed to regulators in April that they be allowed to join an airline after 750 hours of flight time.
There is an exception for certain military experience that cuts the requirement in half for a new pilot to fly commercially.
The 1,500-hour rule was put in place after the Colgan Air crash. The minimum period of rest for pilots was changed following the crash.
The agency said that it considered it to be of greater public interest to ensure and maintain the level of safety provided by the foundation of an integrated aviation education.
The FAA decision comes as airlines struggle with a severe shortfall of pilots, which executives have blamed on service cuts.
Republic Airways didn't say anything.