Narrative:

On the downwind portion of the arrival; in preparation for the ILS; we were cleared to begin a descent from 6;000 ft to 4;000 ft MSL. The cloud tops were approximately 5;500 ft. As we began the descent; I retarded the throttle slightly and pushed the nose over. At the moment of throttle reduction; a considerable rollback of power was noted. Additionally; at the same moment; the engine fire warning light illuminated and the warning horn also went off. The warning light illumination and horn sounding lasted for an approximately 2-3 seconds. The power returned to the power setting I selected seconds after the occurrence. Seconds later; the engine fire warning light illuminated again; along with the warning horn; for an additional 2-3 seconds. During the duration of the event; all engine instruments remained within safe limits. Despite this; we did not want to risk the lives of our passengers or ourselves by continuing the flight longer than necessary. Given the portion of the arrival we were on; we knew we would continue the flight for 10-15 NM prior to receiving a vector inbound to intercept the ILS. With this in mind and the seriousness of the possibility of an engine fire; we [advised ATC]; noted fuel on board; and souls on board. We immediately received a vector to turn left to 360 degrees and a further descent down to 2;500 ft. After a second vector to turn 330 degrees; I intercepted the localizer while continuing the descent. As we neared the airport I intercepted the glideslope and successfully completed the ILS. No engine fire was present upon landing; all engine instruments remained within safe limits.

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Original NASA ASRS Text

Title: Cessna 208 First Officer reported receiving an engine fire warning on approach; but no evidence of fire was found after landing.

Narrative: On the downwind portion of the arrival; in preparation for the ILS; we were cleared to begin a descent from 6;000 ft to 4;000 ft MSL. The cloud tops were approximately 5;500 ft. As we began the descent; I retarded the throttle slightly and pushed the nose over. At the moment of throttle reduction; a considerable rollback of power was noted. Additionally; at the same moment; the engine fire warning light illuminated and the warning horn also went off. The warning light illumination and horn sounding lasted for an approximately 2-3 seconds. The power returned to the power setting I selected seconds after the occurrence. Seconds later; the engine fire warning light illuminated again; along with the warning horn; for an additional 2-3 seconds. During the duration of the event; all engine instruments remained within safe limits. Despite this; we did not want to risk the lives of our passengers or ourselves by continuing the flight longer than necessary. Given the portion of the arrival we were on; we knew we would continue the flight for 10-15 NM prior to receiving a vector inbound to intercept the ILS. With this in mind and the seriousness of the possibility of an engine fire; we [advised ATC]; noted fuel on board; and souls on board. We immediately received a vector to turn left to 360 degrees and a further descent down to 2;500 ft. After a second vector to turn 330 degrees; I intercepted the localizer while continuing the descent. As we neared the airport I intercepted the glideslope and successfully completed the ILS. No engine fire was present upon landing; all engine instruments remained within safe limits.

Data retrieved from NASA's ASRS site 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.