Narrative:

During pushback, the APU generator dropped offline. While trying to re-establish electrical power to aircraft to continue flight (ie, engine start) operations, a ground crew member signaled to the captain that there was an APU fire. The captain verbally confirmed with ground personnel the fire signal, and visually noted smoke near the rear of the aircraft. The APU fire handle was pulled by the captain, and 1 bottle was discharged as a precaution since there were no cockpit indications of an APU fire (ie, APU fire handle, lights, nor fire bell). Ground personnel immediately noted that the flames were gone, and that no further smoke was noticed. I ran the APU fire QRH checklist while the captain requested the crash fire rescue equipment vehicles as a precaution from ground control. Once all indications of smoke or flames were determined to be gone, we were towed back to the gate. A subsequent maintenance inspection by contract maintenance indicated scorching and heat damage to the underside of the right elevator, and the aircraft required further inspection by air carrier maintenance prior to release for next flight. During our ground time in msy, heavy rain fell for 10-15 mins prior to our pushback, and a strong tailwind was present during ground operations. Hands-up play by ground crew member whose vantage point in operations office afforded best view of tailpipe torching incident. Evacuation may have become necessary had the ground personnel on the scene, which may have caused injury to passenger and crew unnecessarily.

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Original NASA ASRS Text

Title: B737-400 CREW HAD THE APU TORCH, TO THE POINT THE ACFT'S R ELEVATOR WAS DAMAGED.

Narrative: DURING PUSHBACK, THE APU GENERATOR DROPPED OFFLINE. WHILE TRYING TO RE-ESTABLISH ELECTRICAL PWR TO ACFT TO CONTINUE FLT (IE, ENG START) OPS, A GND CREW MEMBER SIGNALED TO THE CAPT THAT THERE WAS AN APU FIRE. THE CAPT VERBALLY CONFIRMED WITH GND PERSONNEL THE FIRE SIGNAL, AND VISUALLY NOTED SMOKE NEAR THE REAR OF THE ACFT. THE APU FIRE HANDLE WAS PULLED BY THE CAPT, AND 1 BOTTLE WAS DISCHARGED AS A PRECAUTION SINCE THERE WERE NO COCKPIT INDICATIONS OF AN APU FIRE (IE, APU FIRE HANDLE, LIGHTS, NOR FIRE BELL). GND PERSONNEL IMMEDIATELY NOTED THAT THE FLAMES WERE GONE, AND THAT NO FURTHER SMOKE WAS NOTICED. I RAN THE APU FIRE QRH CHKLIST WHILE THE CAPT REQUESTED THE CFR VEHICLES AS A PRECAUTION FROM GND CTL. ONCE ALL INDICATIONS OF SMOKE OR FLAMES WERE DETERMINED TO BE GONE, WE WERE TOWED BACK TO THE GATE. A SUBSEQUENT MAINT INSPECTION BY CONTRACT MAINT INDICATED SCORCHING AND HEAT DAMAGE TO THE UNDERSIDE OF THE R ELEVATOR, AND THE ACFT REQUIRED FURTHER INSPECTION BY ACR MAINT PRIOR TO RELEASE FOR NEXT FLT. DURING OUR GND TIME IN MSY, HEAVY RAIN FELL FOR 10-15 MINS PRIOR TO OUR PUSHBACK, AND A STRONG TAILWIND WAS PRESENT DURING GND OPS. HANDS-UP PLAY BY GND CREW MEMBER WHOSE VANTAGE POINT IN OPS OFFICE AFFORDED BEST VIEW OF TAILPIPE TORCHING INCIDENT. EVACUATION MAY HAVE BECOME NECESSARY HAD THE GND PERSONNEL ON THE SCENE, WHICH MAY HAVE CAUSED INJURY TO PAX AND CREW UNNECESSARILY.

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.