(Reuters) - US Airways Group (>> US Airways Group Inc) was fined $1.2 million by the U.S. Department of Transportation on Monday for not providing adequate wheelchair assistance to passengers at airports in Philadelphia and Charlotte, North Carolina.

The agency, in a statement, said the fine was one of the largest it has ever made in a disability case.

The DOT said it found infractions regarding wheelchair-assistance requirements in 2011 and 2012 at the two airports. It studied about 300 passenger complaints, and found that the airline's use of electric carts and wheelchairs to carry passengers between gates required frequent transfers and caused lengthy delays.

US Airways, which hopes to merge with American Airlines (>> AMR Corporation) and form the world's largest carrier, said it has made improvements to its disability assistance program since the complaints cited by the DOT.

"We are investing $2 million per year in continuous enhancements to our technology, staffing and training," US Airways said in a statement.

(Reporting by Karen Jacobs in Atlanta; Editing by Leslie Gevirtz)

Stocks treated in this article : US Airways Group Inc, AMR Corporation