The FAA on Friday proposed two separate civil penalties against SkyWest Airlines totaling $1.23 million for alleged safety violations stemming from inadequate maintenance work on six of the company’s Bombardier CRJs. The FAA claimed the company operated two aircraft on a total of 15,969 flights, despite the company’s failure to inspect the cargo door skins for potential cracks at the intervals required in a 2006 airworthiness directive. The AD specifically focused on potential cracks that could affect safety of flight after fatigue testing identified cracks on similar aircraft. Failure to comply with the AD meant the entire aircraft was unairworthy.

The agency also cited SkyWest for its failure to inspect the main landing gear components on four other CRJs at the required wear intervals. The FAA said SkyWest operated the four aircraft on more than 6,700 flights past inspection due dates. The agency has given SkyWest 30 days to respond to the allegations.