The Transport Workers Union of America, which represents ground workers at American Airlines, said yesterday that it has reached an agreement with US Airways Group Inc. and AMR Corp. that would grant immediate raises of 4.3 percent for its members should a merger of the two carriers take place, Reuters reported yesterday. The wage increase is spelled out in a memorandum of understanding reached over the past month with representatives of senior management at US Airways and American Airlines. The memo requires bankruptcy court approval and would take effect should the court approve a merger reorganization plan for American, which sought chapter 11 protection in November 2011.