Narrative:

While at FL300 in cruise configuration the amber cas message fuel imbalance came on. The fuel level showed about 4800 lbs in the left wing and about 3500 lbs in the right wing. First officer took the radios and I complied with the QRH for fuel imbalance message. At the direction of the QRH we diverted to the nearest suitable airport and an emergency was declared. Flight attendant was notified of the diversion and the possibility of a fuel leak. The flight was descended to 11;000 ft and turned direct to the diversion airport. The flight was about 40 NM south of the diversion airport at the time of the incident. After the QRH was complete and while on about a 20 NM final to runway 23L; I assumed pilot flying duties. The flight was operating in VMC at the time of landing and a visual approach was made. Upon disconnection of autopilot the left wing was felt to be heavy. The aircraft was configured at flaps 20 and the vref speed was about 160 KIAS. Upon landing and roll out there were no indications of any problems and braking action was normal. I taxied clear of the runway onto the taxiway for the fire department to have a look at the plane. The fire department informed me that they did see some fuel vapor and drips on the right wing. Due to the fact that the fuel leak was minor at the time; I decided to continue the taxi to the ramp area in order to safely deplane the passengers. The first indication that was noticed was the amber cas message. At the time of takeoff when the before takeoff check was made of the imbalance was about 200 lbs difference. It is unknown at this time why the imbalance occurred. The auto crossflow was not able to correct the imbalance and manual was not attempted in case there was a leak in the right wing or engine. The fuel flow was checked at cruise power settings and observed to be close to even on left and right engines. Once on the ground and passengers deplaned the manual crossflow was able to correct the imbalance. At the direction of the QRH the fuel crossflow was put into manual and the transfer of fuel from left wing to right wing was stopped. Landing was made with about 4500 lbs in the left wing and 3300 lbs in the right wing.

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Original NASA ASRS Text

Title: CRJ200 flight crew experiences fuel imbalance CAS message at FL300. A fuel leak is suspected and the crew elects to divert to the nearest suitable airport.

Narrative: While at FL300 in cruise configuration the Amber CAS message FUEL IMBALANCE came on. The fuel level showed about 4800 lbs in the left wing and about 3500 lbs in the right wing. First Officer took the radios and I complied with the QRH for Fuel Imbalance message. At the direction of the QRH we diverted to the nearest suitable airport and an emergency was declared. Flight Attendant was notified of the diversion and the possibility of a fuel leak. The flight was descended to 11;000 ft and turned direct to the diversion airport. The flight was about 40 NM south of the diversion airport at the time of the incident. After the QRH was complete and while on about a 20 NM final to runway 23L; I assumed pilot flying duties. The flight was operating in VMC at the time of landing and a visual approach was made. Upon disconnection of autopilot the left wing was felt to be heavy. The aircraft was configured at Flaps 20 and the Vref speed was about 160 KIAS. Upon landing and roll out there were no indications of any problems and braking action was normal. I taxied clear of the runway onto the taxiway for the fire department to have a look at the plane. The fire department informed me that they did see some fuel vapor and drips on the right wing. Due to the fact that the fuel leak was minor at the time; I decided to continue the taxi to the ramp area in order to safely deplane the passengers. The first indication that was noticed was the amber CAS message. At the time of takeoff when the before takeoff check was made of the imbalance was about 200 lbs difference. It is unknown at this time why the imbalance occurred. The auto crossflow was not able to correct the imbalance and manual was not attempted in case there was a leak in the right wing or engine. The fuel flow was checked at cruise power settings and observed to be close to even on left and right engines. Once on the ground and passengers deplaned the manual crossflow was able to correct the imbalance. At the direction of the QRH the fuel crossflow was put into manual and the transfer of fuel from left wing to right wing was stopped. Landing was made with about 4500 lbs in the left wing and 3300 lbs in the right wing.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.