U.S. aviation regulators proposed a $4.8 million fine against cargo carrier Evergreen International Airlines for allegedly not training pilots fully on a new cockpit software system.

The Federal Aviation Administration (FAA) said privately held Evergreen allowed pilots on more than 200 flights in 2009 whose training on a the upgraded flight management system did not fully meet federal requirements.

That system is an on-board computer network that helps the crew with satellite-based navigation and can assist with engine thrust control and fuel monitoring.

Evergreen is currently in full compliance with the training regulation, the FAA said.

Evergreen said in a statement the case should never have been brought and represented a "good faith dispute" about appropriate training when the carrier changed from one flight management system to another.

The company said it would challenge the proposed fine. (Reuters)