Narrative:

On initial stages of descent (approximately 50 mi north) into ZZZ #2 engine fire warning illuminated and alarmed. Appropriate checklists were complete and both fire extinguisher bottles were discharged. Fire warning lights remained illuminated. Captain contacted flight attendant B to visually verify for any signs of fire; smoke; or leaking fluids. Flight attendant replied back negative on all accounts. Remaining checklists were completed. Delay vectors were requested of ATC and received for the purposes of completing those checklists. Both runways served by ILS's were closed and an RNAV xx was done to comply with checklist requiring vertical guidance for the approach and landing. Landing was completed without incident. Engine fire warning went out on touchdown. Maintenance indicated a failure of the forward fire detection loop. As is the case many times checklists don't cover all aspects of a situation. In this case a judgement was made that there was a very high likelihood no fire existed. In this case the crew determined that the risk level was higher of a further compounding incident by not doing all relevant checklist and landing immediately than the risk of a fire that probably didn't exist. Had the engine really been burning and been unable to extinguish we could have landed more quickly. This was reminiscent of a dash 8-100 that had an uncontrolled #2 engine fire many yrs ago. This weighed very heavily on my mind as we progressed through this problem.

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Original NASA ASRS Text

Title: DASH8 FLT CREW REPORTS ENG FIRE WARNING DURING DESCENT WHICH DOES NOT EXTINGUISH AFTER SHUTDOWN AND TWO FIRE BOTTLES. FLT ATTENDANT REPORTS NO VISIBLE FIRE AND FLT CREW LANDS SAFELY AT DESTINATION.

Narrative: ON INITIAL STAGES OF DSCNT (APPROX 50 MI N) INTO ZZZ #2 ENG FIRE WARNING ILLUMINATED AND ALARMED. APPROPRIATE CHKLISTS WERE COMPLETE AND BOTH FIRE EXTINGUISHER BOTTLES WERE DISCHARGED. FIRE WARNING LIGHTS REMAINED ILLUMINATED. CAPT CONTACTED FLT ATTENDANT B TO VISUALLY VERIFY FOR ANY SIGNS OF FIRE; SMOKE; OR LEAKING FLUIDS. FLT ATTENDANT REPLIED BACK NEGATIVE ON ALL ACCOUNTS. REMAINING CHKLISTS WERE COMPLETED. DELAY VECTORS WERE REQUESTED OF ATC AND RECEIVED FOR THE PURPOSES OF COMPLETING THOSE CHKLISTS. BOTH RWYS SERVED BY ILS'S WERE CLOSED AND AN RNAV XX WAS DONE TO COMPLY WITH CHKLIST REQUIRING VERT GUIDANCE FOR THE APCH AND LNDG. LNDG WAS COMPLETED WITHOUT INCIDENT. ENG FIRE WARNING WENT OUT ON TOUCHDOWN. MAINT INDICATED A FAILURE OF THE FORWARD FIRE DETECTION LOOP. AS IS THE CASE MANY TIMES CHKLISTS DON'T COVER ALL ASPECTS OF A SITUATION. IN THIS CASE A JUDGEMENT WAS MADE THAT THERE WAS A VERY HIGH LIKELIHOOD NO FIRE EXISTED. IN THIS CASE THE CREW DETERMINED THAT THE RISK LEVEL WAS HIGHER OF A FURTHER COMPOUNDING INCIDENT BY NOT DOING ALL RELEVANT CHKLIST AND LNDG IMMEDIATELY THAN THE RISK OF A FIRE THAT PROBABLY DIDN'T EXIST. HAD THE ENG REALLY BEEN BURNING AND BEEN UNABLE TO EXTINGUISH WE COULD HAVE LANDED MORE QUICKLY. THIS WAS REMINISCENT OF A DASH 8-100 THAT HAD AN UNCTLED #2 ENG FIRE MANY YRS AGO. THIS WEIGHED VERY HEAVILY ON MY MIND AS WE PROGRESSED THROUGH THIS PROB.

Data retrieved from NASA's ASRS site as of January 2009 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.