A PSA Airlines Canadair CRJ-900 on behalf of American Airlines, registration N547NN performing flight AA-5209 from Charlotte,NC to Cincinnati,KY (USA), was climbing out of Charlotte's runway 36C when the crew declared emergency reporting a gear disagree issue subsequently advising the gear didn't want to come up. The crew stopped the climb at 8000 feet and returned to Charlotte for a safe landing on runway 36C about 20 minutes after departure.
The aircraft remained on the ground for about 2 hours, then departed again and reached Cincinnati with a delay of 110 minutes.