Narrative:

We were en route dro-sna. In our climb through FL290 we had a fire indication in the left engine. The situation was handled as follows: starting with the emergency checklist and at the same time notifying ATC that we needed to descend to a suitable airport, they recommended fmn. It was close by and has the proper runway lengths. We agreed and were cleared to descend and started towards fmn. We did not declare an emergency but immediately started down to land. Proceeding we closed the throttle on the left engine to see if the fire indication would go out. It did not, so we agreed to shut down the left engine, which when completed still did not solve the problem. Then we closed the firewall shutoff which arms the fire bottles. After this procedure was completed the fire indication went out. At that time we notified ATC that our situation was stable and that our descent and landing should be normal from that time forward but they should be aware that we were single engine. We completed the engine securing checklist and returned to land without incident. After landing we pulled the cowling on the left engine to trouble-shoot the problem. The captain is an a&P and I have lots of experience working on this aircraft. We found a simple fire loop indication problem which was corrected with thermal tape. We were able to continue the flight without further incident. This was a mechanical problem and could not have been prevented or improved on by pilot technique.

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Original NASA ASRS Text

Title: ATX LTT DIVERTS TO ALTERNATE AFTER RECEIVING A FIRE WARNING FROM THE L ENG.

Narrative: WE WERE ENRTE DRO-SNA. IN OUR CLB THROUGH FL290 WE HAD A FIRE INDICATION IN THE L ENG. THE SIT WAS HANDLED AS FOLLOWS: STARTING WITH THE EMER CHKLIST AND AT THE SAME TIME NOTIFYING ATC THAT WE NEEDED TO DSND TO A SUITABLE ARPT, THEY RECOMMENDED FMN. IT WAS CLOSE BY AND HAS THE PROPER RWY LENGTHS. WE AGREED AND WERE CLRED TO DSND AND STARTED TOWARDS FMN. WE DID NOT DECLARE AN EMER BUT IMMEDIATELY STARTED DOWN TO LAND. PROCEEDING WE CLOSED THE THROTTLE ON THE L ENG TO SEE IF THE FIRE INDICATION WOULD GO OUT. IT DID NOT, SO WE AGREED TO SHUT DOWN THE L ENG, WHICH WHEN COMPLETED STILL DID NOT SOLVE THE PROB. THEN WE CLOSED THE FIREWALL SHUTOFF WHICH ARMS THE FIRE BOTTLES. AFTER THIS PROC WAS COMPLETED THE FIRE INDICATION WENT OUT. AT THAT TIME WE NOTIFIED ATC THAT OUR SIT WAS STABLE AND THAT OUR DSCNT AND LNDG SHOULD BE NORMAL FROM THAT TIME FORWARD BUT THEY SHOULD BE AWARE THAT WE WERE SINGLE ENG. WE COMPLETED THE ENG SECURING CHKLIST AND RETURNED TO LAND WITHOUT INCIDENT. AFTER LNDG WE PULLED THE COWLING ON THE L ENG TO TROUBLE-SHOOT THE PROB. THE CAPT IS AN A&P AND I HAVE LOTS OF EXPERIENCE WORKING ON THIS ACFT. WE FOUND A SIMPLE FIRE LOOP INDICATION PROB WHICH WAS CORRECTED WITH THERMAL TAPE. WE WERE ABLE TO CONTINUE THE FLT WITHOUT FURTHER INCIDENT. THIS WAS A MECHANICAL PROB AND COULD NOT HAVE BEEN PREVENTED OR IMPROVED ON BY PLT TECHNIQUE.

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