Narrative:

While taxiing for takeoff, during delayed engine start procedure, a fire erupted in the left engine. There were no cockpit indications of any problems, other than no egt rise. We were alerted of the fire by another aircraft taxiing behind us. Fire was extinguished by motoring the engine with no further problems experienced. However, emergency equipment was called out, and followed us on our return to the gate. Maintenance found a failed 'B' ignition system.

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Original NASA ASRS Text

Title: ACFT EQUIP PROB. FAILED B IGNITION SYS ENG FIRE.

Narrative: WHILE TAXIING FOR TKOF, DURING DELAYED ENG START PROC, A FIRE ERUPTED IN THE L ENG. THERE WERE NO COCKPIT INDICATIONS OF ANY PROBS, OTHER THAN NO EGT RISE. WE WERE ALERTED OF THE FIRE BY ANOTHER ACFT TAXIING BEHIND US. FIRE WAS EXTINGUISHED BY MOTORING THE ENG WITH NO FURTHER PROBS EXPERIENCED. HOWEVER, EMER EQUIP WAS CALLED OUT, AND FOLLOWED US ON OUR RETURN TO THE GATE. MAINT FOUND A FAILED 'B' IGNITION SYS.

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.