Narrative:

I was pilot flying with an initial operator experience (IOE) captain student in left seat. Lost right overwing fuel filler cap at rotation. Initial report from tower was smoke coming from right engine. No fire/failure was indicated. Aircraft behind us then told us it was fuel coming from right wing. Commuting captain informed flight attendants of loss of fuel cap. Performed fuel leak checklist after declaring an emergency with approach and diverted to a nearby airport. Approach notified operations for us and we requested crash fire rescue equipment. [I] [briefed] flight attendants. Because of large fuel imbalance and unknown status of fuel leak I exercised captain's authority and expedited landing at the nearby airport. Isolated fuel tank; did not finish fuel leak checklist which called for a flaps 20 landing. Landed overweight at flaps 45; 71;000 pounds speed card. Actual weight was probably close to 69;000 pounds. Performed all normal checklists and verified runway landing performance; landed with 200 FPM descent rate; rolled out to end of runway; met by crash fire rescue equipment who inspected aircraft for active fuel leak and any fire hazard. None was found; taxied to gate and deplaned. The cause is unknown because aircraft was fueled by normal single point fueling method. No problems were indicated to me by fuelers.

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Original NASA ASRS Text

Title: CRJ700 flight crew is informed of fuel loss from the right wing during rotation. An EICAS Fuel Imbalance message is noted and crew elects to divert to an airport with a longer runway; without running the fuel leak checklist to its completion.

Narrative: I was pilot flying with an Initial Operator Experience (IOE) Captain student in left seat. Lost right overwing fuel filler cap at rotation. Initial report from Tower was smoke coming from right engine. No fire/failure was indicated. Aircraft behind us then told us it was fuel coming from right wing. Commuting Captain informed flight attendants of loss of fuel cap. Performed Fuel Leak checklist after declaring an emergency with Approach and diverted to a nearby airport. Approach notified Operations for us and we requested CFR. [I] [briefed] Flight Attendants. Because of large fuel imbalance and unknown status of fuel leak I exercised Captain's authority and expedited landing at the nearby airport. Isolated fuel tank; did not finish Fuel Leak checklist which called for a flaps 20 landing. Landed overweight at flaps 45; 71;000 LBS speed card. Actual weight was probably close to 69;000 LBS. Performed all normal checklists and verified runway landing performance; landed with 200 FPM descent rate; rolled out to end of runway; met by CFR who inspected aircraft for active fuel leak and any fire hazard. None was found; taxied to gate and deplaned. The cause is unknown because aircraft was fueled by normal single point fueling method. No problems were indicated to me by fuelers.

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.