Narrative:

During preflight, we discovered the #1 nacelle cowl anti-ice valve was discovered open and we referred to company MEL and coordinated with company for contract maintenance. Mechanic stated he deactivated wing and engine anti-ice circuit breakers to close valves. Valves indicated closed. We loaded passenger and pushed and started engines. The right engine started normally, however, when the right generator was placed on line, the left bus fell off the APU. Checked circuit breakers and didn't see any open. Captain also checked. Verified APU was still running. Captain suggested starting #1 and we should be able to regain the left bus. Being relatively new, I had some reservations about starting until we solved the abnormal. But we were late, so I deferred to his experience. During start attempt on #1 engine, no light off occurred. We put the fuel control lever to cutoff and waited for N1 to wind down so we could motor. At this point the tug driver pointed out to us that he observed some smoke on the left engine. We assumed it was residue from the aborted start attempt. We decided the engine wasn't going to start and asked the tug driver to pull us back to the gate. While he was pulling us, he stated that we had a fire in the left engine. There were no indications of engine fire in the cockpit, but we still pulled the handle and discharged 1 bottle and made a call for fire equipment. The captain requested the passenger remain seated and announced we had a problem starting the left engine and stand by for further instruction. The fire department was on scene almost immediately and were directed to the left engine. They extinguished a small tail pipe fire. With the fire safely out, we requested stairs for the right forward door and the captain directed an orderly deplanement. Aircraft was turned over for maintenance. They discovered an unlabeled circuit breaker open on the G5 rack. This circuit breaker isn't readily visible at the time but affected the APU generator control. This may have resulted in the hung slow or no start. Only 1 ignitor would have been only pwred by battery if at all. Corrective action at best, include labeling and functions of G5 racks in reference manuals.

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Original NASA ASRS Text

Title: FLC OF A B737-200 EXPERIENCED AN ENG FIRE AFTER AN IGNITION MALFUNCTION CAUSED THE ENG TO NOT START. THE CREW DISCHARGED 1 FIRE BOTTLE AND CALLED UPON THE FIRE DEPT TO SECURE THE REST. THE PAX WERE ORDERLY DEPLANED ASAP.

Narrative: DURING PREFLT, WE DISCOVERED THE #1 NACELLE COWL ANTI-ICE VALVE WAS DISCOVERED OPEN AND WE REFERRED TO COMPANY MEL AND COORDINATED WITH COMPANY FOR CONTRACT MAINT. MECH STATED HE DEACTIVATED WING AND ENG ANTI-ICE CIRCUIT BREAKERS TO CLOSE VALVES. VALVES INDICATED CLOSED. WE LOADED PAX AND PUSHED AND STARTED ENGS. THE R ENG STARTED NORMALLY, HOWEVER, WHEN THE R GENERATOR WAS PLACED ON LINE, THE L BUS FELL OFF THE APU. CHKED CIRCUIT BREAKERS AND DIDN'T SEE ANY OPEN. CAPT ALSO CHKED. VERIFIED APU WAS STILL RUNNING. CAPT SUGGESTED STARTING #1 AND WE SHOULD BE ABLE TO REGAIN THE L BUS. BEING RELATIVELY NEW, I HAD SOME RESERVATIONS ABOUT STARTING UNTIL WE SOLVED THE ABNORMAL. BUT WE WERE LATE, SO I DEFERRED TO HIS EXPERIENCE. DURING START ATTEMPT ON #1 ENG, NO LIGHT OFF OCCURRED. WE PUT THE FUEL CTL LEVER TO CUTOFF AND WAITED FOR N1 TO WIND DOWN SO WE COULD MOTOR. AT THIS POINT THE TUG DRIVER POINTED OUT TO US THAT HE OBSERVED SOME SMOKE ON THE L ENG. WE ASSUMED IT WAS RESIDUE FROM THE ABORTED START ATTEMPT. WE DECIDED THE ENG WASN'T GOING TO START AND ASKED THE TUG DRIVER TO PULL US BACK TO THE GATE. WHILE HE WAS PULLING US, HE STATED THAT WE HAD A FIRE IN THE L ENG. THERE WERE NO INDICATIONS OF ENG FIRE IN THE COCKPIT, BUT WE STILL PULLED THE HANDLE AND DISCHARGED 1 BOTTLE AND MADE A CALL FOR FIRE EQUIP. THE CAPT REQUESTED THE PAX REMAIN SEATED AND ANNOUNCED WE HAD A PROB STARTING THE L ENG AND STAND BY FOR FURTHER INSTRUCTION. THE FIRE DEPT WAS ON SCENE ALMOST IMMEDIATELY AND WERE DIRECTED TO THE L ENG. THEY EXTINGUISHED A SMALL TAIL PIPE FIRE. WITH THE FIRE SAFELY OUT, WE REQUESTED STAIRS FOR THE R FORWARD DOOR AND THE CAPT DIRECTED AN ORDERLY DEPLANEMENT. ACFT WAS TURNED OVER FOR MAINT. THEY DISCOVERED AN UNLABELED CIRCUIT BREAKER OPEN ON THE G5 RACK. THIS CIRCUIT BREAKER ISN'T READILY VISIBLE AT THE TIME BUT AFFECTED THE APU GENERATOR CTL. THIS MAY HAVE RESULTED IN THE HUNG SLOW OR NO START. ONLY 1 IGNITOR WOULD HAVE BEEN ONLY PWRED BY BATTERY IF AT ALL. CORRECTIVE ACTION AT BEST, INCLUDE LABELING AND FUNCTIONS OF G5 RACKS IN REF MANUALS.

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.