Narrative:

On takeoff runway 27R at atl, loud buffeting and vibration was encountered. No cockpit indications or warnings. Declared an emergency. Returned to land on runway 9R uneventfully. While taxiing in, ramp control notified us that the cargo door was open. Cause: ramp and flight crew failed to assure cargo door was closed. Contributing factors: cargo door light in cockpit was inoperative (deferred). I believe that this situation would not have occurred if the cargo door light had not been deferred per the MEL. Supplemental information from acn 352123: I was going through aircraft log and found the cargo warning light deferred. Paperwork said the 'cargo door light will not extinguish' but the light was extinguished. Major mistake assuming it was closed and locked.

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Original NASA ASRS Text

Title: AN ACR LTT TOOK OFF WITH A CARGO DOOR OPEN.

Narrative: ON TKOF RWY 27R AT ATL, LOUD BUFFETING AND VIBRATION WAS ENCOUNTERED. NO COCKPIT INDICATIONS OR WARNINGS. DECLARED AN EMER. RETURNED TO LAND ON RWY 9R UNEVENTFULLY. WHILE TAXIING IN, RAMP CTL NOTIFIED US THAT THE CARGO DOOR WAS OPEN. CAUSE: RAMP AND FLC FAILED TO ASSURE CARGO DOOR WAS CLOSED. CONTRIBUTING FACTORS: CARGO DOOR LIGHT IN COCKPIT WAS INOP (DEFERRED). I BELIEVE THAT THIS SIT WOULD NOT HAVE OCCURRED IF THE CARGO DOOR LIGHT HAD NOT BEEN DEFERRED PER THE MEL. SUPPLEMENTAL INFO FROM ACN 352123: I WAS GOING THROUGH ACFT LOG AND FOUND THE CARGO WARNING LIGHT DEFERRED. PAPERWORK SAID THE 'CARGO DOOR LIGHT WILL NOT EXTINGUISH' BUT THE LIGHT WAS EXTINGUISHED. MAJOR MISTAKE ASSUMING IT WAS CLOSED AND LOCKED.

Data retrieved from NASA's ASRS site as of July 2007 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.