Narrative:

Immediately after takeoff, we received a fire warning on the left engine. After retarding the throttle, the warning stopped. Left engine was shut down as a precaution, we declared an emergency and landed at jfk. I was flying initially, but the captain did the single engine approach and landing. Upon inspection, a broken anti-ice duct was found to have been blowing hot bleed air on the fire detect loops. The duct was replaced and the flight continued as planned.

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Original NASA ASRS Text

Title: ACR MLG ENGINE FIRE WARNING IN CLIMB. INFLT SHUTDOWN. DIVERTED TO ALTERNATE ARPT AND LANDED. EMERGENCY DECLARED.

Narrative: IMMEDIATELY AFTER TKOF, WE RECEIVED A FIRE WARNING ON THE LEFT ENGINE. AFTER RETARDING THE THROTTLE, THE WARNING STOPPED. LEFT ENGINE WAS SHUT DOWN AS A PRECAUTION, WE DECLARED AN EMER AND LANDED AT JFK. I WAS FLYING INITIALLY, BUT THE CAPT DID THE SINGLE ENGINE APCH AND LNDG. UPON INSPECTION, A BROKEN ANTI-ICE DUCT WAS FOUND TO HAVE BEEN BLOWING HOT BLEED AIR ON THE FIRE DETECT LOOPS. THE DUCT WAS REPLACED AND THE FLT CONTINUED AS PLANNED.

Data retrieved from NASA's ASRS site as of August 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.