Narrative:

Shortly after flaps up on takeoff we experienced a flicker of the engine fire warning bell, but were unable to determine which light. We suspected #1 engine because of a previous write-up, but could not confirm. We made visibility checks on #1 and #3 engines, revealing no problems, and made an immediate smooth overweight landing on runway 24R at yyz. On roll-out we experienced a definite flicker of #1 engine fire warning light and bell. We executed the fire checklist and had the fire department make a visibility check. Since no problems were revealed we taxied to the gate. The maintenance fix was to replace the 4 fire detected loops.

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Original NASA ASRS Text

Title: ACFT EXPERIENCED INTERMITTENT FIRE BELL ACTIVATION IMMEDIATELY AFTER TKOF. RETURN TO DEP ARPT.

Narrative: SHORTLY AFTER FLAPS UP ON TKOF WE EXPERIENCED A FLICKER OF THE ENG FIRE WARNING BELL, BUT WERE UNABLE TO DETERMINE WHICH LIGHT. WE SUSPECTED #1 ENG BECAUSE OF A PREVIOUS WRITE-UP, BUT COULD NOT CONFIRM. WE MADE VIS CHKS ON #1 AND #3 ENGS, REVEALING NO PROBS, AND MADE AN IMMEDIATE SMOOTH OVERWEIGHT LNDG ON RWY 24R AT YYZ. ON ROLL-OUT WE EXPERIENCED A DEFINITE FLICKER OF #1 ENG FIRE WARNING LIGHT AND BELL. WE EXECUTED THE FIRE CHKLIST AND HAD THE FIRE DEPT MAKE A VIS CHK. SINCE NO PROBS WERE REVEALED WE TAXIED TO THE GATE. THE MAINT FIX WAS TO REPLACE THE 4 FIRE DETECTED LOOPS.

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