A Piedmont Embraer ERJ-145 on behalf of American Airlines, registration N634AE performing flight AA-4764 from Charlotte,NC to Lexington,KY (USA), was climbing out of Charlotte when the crew declared emergency reporting fumes on board further explaining there was a smell on board, that was not normal. The aircraft stopped the climb at about 9000 feet and returned to Charlotte for a safe landing on runway 18C about 15 minutes after departure.
A replacement ERJ-145 registration N645AE reached Lexington with a delay of about 3 hours.
The occurrence aircraft remained on the ground for about 17.4 hours, then departed for positioning flight to Salisbury,MD (USA) but needed to declare emergency and return to Charlotte again landing safely about 7 minutes after departure.