 During the course of its investigation , the Federal Aviation Administration ( FAA ) discovered that tower staffing levels at Blue Grass Airport violated an internal policy as reflected in a November 16 , 2005 , memorandum requiring two controllers during the overnight shift : one in the tower working clearance , ground , and tower frequencies , and another , either in the tower or <unk> at Indianapolis Center , working <unk> ( radar ) . At the time of the accident , the single controller in the tower was performing both tower and radar duties . On August 30 , 2006 , the FAA announced that Lexington , as well as other airports with similar traffic levels , would be staffed with two controllers in the tower around the clock effective immediately . 
