Narrative:

During the taxi from the hangar to the gate, after entering the ramp area, the left engine fire warning system illuminated and sounded. We then applied the shutdown and extinguishing procedures as per our flight standards manual. Fire equipment was requested. After the extinguishing procedure was complete, the system was still activated, so we applied the evacuate/evacuation procedures per our flight standards manual (only the crew was aboard). The fire crew found no fire present. After crash fire rescue equipment cleared the aircraft as safe, we taxied the aircraft, on the right engine, back to the hangar. One of our company mechanics were flown in, and he worked on the aircraft for several hours. He stated he found nothing out of the ordinary, but he changed the fire control sensor as a precaution and signed off the aircraft as repaired. Our company dispatch assigned us to repos the aircraft back to iad from buf. After preflting and obtaining an IFR clearance, we taxied to runway 5 for takeoff. After being cleared for takeoff, during the takeoff roll approximately 5 KTS below V1, the left engine fire warning system activated again. We discontinued the takeoff. During the power reduction, the warning system deactivated, and all lights and bells extinguished. After clearing the runway the engine was shut down as a precautionary measure (an emergency no longer existed). We then taxied to our ramp area, where the mechanic onboard inspected the engine.

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Original NASA ASRS Text

Title: TKOF ABORTED FOR FIRE WARNING.

Narrative: DURING THE TAXI FROM THE HANGAR TO THE GATE, AFTER ENTERING THE RAMP AREA, THE L ENG FIRE WARNING SYS ILLUMINATED AND SOUNDED. WE THEN APPLIED THE SHUTDOWN AND EXTINGUISHING PROCS AS PER OUR FLT STANDARDS MANUAL. FIRE EQUIP WAS REQUESTED. AFTER THE EXTINGUISHING PROC WAS COMPLETE, THE SYS WAS STILL ACTIVATED, SO WE APPLIED THE EVAC PROCS PER OUR FLT STANDARDS MANUAL (ONLY THE CREW WAS ABOARD). THE FIRE CREW FOUND NO FIRE PRESENT. AFTER CFR CLRED THE ACFT AS SAFE, WE TAXIED THE ACFT, ON THE R ENG, BACK TO THE HANGAR. ONE OF OUR COMPANY MECHS WERE FLOWN IN, AND HE WORKED ON THE ACFT FOR SEVERAL HRS. HE STATED HE FOUND NOTHING OUT OF THE ORDINARY, BUT HE CHANGED THE FIRE CTL SENSOR AS A PRECAUTION AND SIGNED OFF THE ACFT AS REPAIRED. OUR COMPANY DISPATCH ASSIGNED US TO REPOS THE ACFT BACK TO IAD FROM BUF. AFTER PREFLTING AND OBTAINING AN IFR CLRNC, WE TAXIED TO RWY 5 FOR TKOF. AFTER BEING CLRED FOR TKOF, DURING THE TKOF ROLL APPROX 5 KTS BELOW V1, THE L ENG FIRE WARNING SYS ACTIVATED AGAIN. WE DISCONTINUED THE TKOF. DURING THE PWR REDUCTION, THE WARNING SYS DEACTIVATED, AND ALL LIGHTS AND BELLS EXTINGUISHED. AFTER CLRING THE RWY THE ENG WAS SHUT DOWN AS A PRECAUTIONARY MEASURE (AN EMER NO LONGER EXISTED). WE THEN TAXIED TO OUR RAMP AREA, WHERE THE MECH ONBOARD INSPECTED THE ENG.

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.