Narrative:

On descent/arrival; at approximately FL250; the right (number 2) engine fire warning light illuminated with the corresponding bell. The first officer was the pilot flying and accomplished the immediate action items. Prior to shutdown; there were no abnormal indications on the number 2 engine. We declared an emergency with center and indicated our intention to land at destination. We accomplished the engine fire; severe damage; separation checklist and the single engine landing checklist. I briefly informed the flight attendants that we had shut down an engine; but that there was no immediate concern. I also informed the passengers of the same; while comforting them that the aircraft flies fine on one engine; and that we would be landing shortly. We received vectors to final and then were cleared a visual approach. We flew the prescribed 15 flap approach and landed uneventfully. We cleared the runway and had the fire crews inspected the engine. Once cleared by the fire chief; we taxied to the gate and deplaned the passengers. As a note; this was our second flight on this aircraft this morning. Prior to the first flight; the fire detection panel tested 'bad' on the B loop for the number 2 engine. We had the B loop deferred prior to that flight. I believe this plane had a faulty fire detection system.

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Original NASA ASRS Text

Title: B737 Captain experiences a right engine fire warning during descent with the First Officer flying. The engine is shut down in accordance with QRH procedures and the flight continues to destination for a single engine landing. The Captain believes the warning was false as the B loop had been deferred prior to the first flight of the day.

Narrative: On descent/arrival; at approximately FL250; the right (Number 2) Engine Fire Warning light illuminated with the corresponding bell. The First Officer was the Pilot Flying and accomplished the immediate action items. Prior to shutdown; there were no abnormal indications on the Number 2 engine. We declared an emergency with Center and indicated our intention to land at destination. We accomplished the Engine Fire; Severe Damage; Separation Checklist and the Single Engine Landing Checklist. I briefly informed the flight attendants that we had shut down an engine; but that there was no immediate concern. I also informed the Passengers of the same; while comforting them that the aircraft flies fine on one engine; and that we would be landing shortly. We received vectors to final and then were cleared a visual approach. We flew the prescribed 15 flap approach and landed uneventfully. We cleared the runway and had the fire crews inspected the engine. Once cleared by the Fire Chief; we taxied to the gate and deplaned the passengers. As a note; this was our second flight on this aircraft this morning. Prior to the first flight; the fire detection panel tested 'bad' on the B loop for the Number 2 engine. We had the B loop deferred prior to that flight. I believe this plane had a faulty fire detection system.

Data retrieved from NASA's ASRS site as of July 2013 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.