The Federal Aviation Administration rejected Republic Airways' proposal to slash the number of hours its pilots would need to become co-pilots.
Pilots currently need at least 1,500 hours of experience to fly a commercial airliner.
Republic Airways reportedly wanted to FAA to cut the requirement to 750 for pilots who graduated from its Lift Academy. That would be on par with the requirements for pilots who have military experience.
The FAA reportedly concluded that Lift Academy does not provide enough training to permit a reduction in flight experience.
Republic Airways says it operates 1,000 flights per day in 100 U.S. cities. It is a regional carrier for American, Delta, and United.
The Regional Airline Association supported Republic Airways' proposal. However, the largest pilot's union in the world, the Air Line Pilots Association, opposed the change in training hours.