Narrative:

Upon gear retraction [after takeoff]; we received a master caution 'left fire det fail' (left fire detector fail). We accomplished the appropriate QRH for that indication and elected to continue the flight while monitoring engine parameters closely. The light eventually went out on its own; but then illuminated again and again. At this point we started discussing a possible return to our departure airport. Shortly after this we received a master warning and 'left engine fire' light. This light extinguished on its own; but just as before with the 'left fire det fail'; the 'left engine fire' light went on and off. We elected to keep the engine running because we figured the 'left engine fire' master warning was associated with the 'left fire det fail' light and we saw no abnormal engine indications and no fire was seen from the captain's side window. Both the master warning and master caution continued to go on and off as we made our approach into the departure airport. After landing; we taxied into the gate without either the master caution or the master warning lights. Once we shut down the left engine and we were parked at the gate; we immediately received a master warning and 'left engine fire'. This time the master warning and 'left engine fire' lights remained illuminated; and the itt was rising. We decided to back away the jet bridge; run the emergency evacuation checklist (pull left fire handle and left fire extinguisher switch) and evacuate the aircraft from the right side. I called the tower and requested crash/fire/rescue for possible left engine fire.

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Original NASA ASRS Text

Title: A SF340's Fire Warning and Fire Detections systems were both giving intermittent warnings in flight so the Captain returned to the departure airport and at the gate the Fire Warning annunciated. The Captain ordered an evacuation and called for the Airport Crash Fire Crew.

Narrative: Upon gear retraction [after takeoff]; we received a Master Caution 'L FIRE DET FAIL' (Left Fire Detector Fail). We accomplished the appropriate QRH for that indication and elected to continue the flight while monitoring engine parameters closely. The light eventually went out on its own; but then illuminated again and again. At this point we started discussing a possible return to our departure airport. Shortly after this we received a Master Warning and 'L ENG FIRE' light. This light extinguished on its own; but just as before with the 'L FIRE DET FAIL'; the 'L ENG FIRE' light went on and off. We elected to keep the engine running because we figured the 'L ENG FIRE' Master Warning was associated with the 'L FIRE DET FAIL' light and we saw no abnormal engine indications and no fire was seen from the Captain's side window. Both the Master Warning and Master Caution continued to go on and off as we made our approach into the departure airport. After landing; we taxied into the gate without either the Master Caution or the Master Warning lights. Once we shut down the left engine and we were parked at the gate; we immediately received a Master Warning and 'L ENG FIRE'. This time the Master Warning and 'L ENG FIRE' lights remained illuminated; and the ITT was rising. We decided to back away the Jet Bridge; run the emergency evacuation checklist (pull left fire handle and left fire extinguisher switch) and evacuate the aircraft from the right side. I called the Tower and requested Crash/Fire/Rescue for possible left engine fire.

Data retrieved from NASA's ASRS site as of April 2012 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.