Narrative:

I attempted to start the APU on aircraft. After 3 unsuccessful attempts a mechanic boarded the aircraft and announced the APU was on fire. I immediately depowered the aircraft and exited. There was no indication of an APU fire in the cockpit. The APU was placarded as inoperative. Callback conversation with reporter revealed the following: asked reporter if there was an APU fire procedure to be followed. He said there was, but he never used it because he never got an APU fire warning. He said the APU was damaged but there was no airframe damage. He said that, after deplaning, the mechanic reboarded the aircraft, powered it up and discharged the fire bottle into the APU. This reduced but did not extinguish the fire. Other ground personnel used a ramp fire extinguisher to finally extinguish the fire. There was comment that the fire extinguishing agent did more damage than the fire.

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Original NASA ASRS Text

Title: LTT HAD AN APU FIRE WHILE PARKED ON THE RAMP.

Narrative: I ATTEMPTED TO START THE APU ON ACFT. AFTER 3 UNSUCCESSFUL ATTEMPTS A MECH BOARDED THE ACFT AND ANNOUNCED THE APU WAS ON FIRE. I IMMEDIATELY DEPOWERED THE ACFT AND EXITED. THERE WAS NO INDICATION OF AN APU FIRE IN THE COCKPIT. THE APU WAS PLACARDED AS INOP. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: ASKED RPTR IF THERE WAS AN APU FIRE PROC TO BE FOLLOWED. HE SAID THERE WAS, BUT HE NEVER USED IT BECAUSE HE NEVER GOT AN APU FIRE WARNING. HE SAID THE APU WAS DAMAGED BUT THERE WAS NO AIRFRAME DAMAGE. HE SAID THAT, AFTER DEPLANING, THE MECH REBOARDED THE ACFT, POWERED IT UP AND DISCHARGED THE FIRE BOTTLE INTO THE APU. THIS REDUCED BUT DID NOT EXTINGUISH THE FIRE. OTHER GND PERSONNEL USED A RAMP FIRE EXTINGUISHER TO FINALLY EXTINGUISH THE FIRE. THERE WAS COMMENT THAT THE FIRE EXTINGUISHING AGENT DID MORE DAMAGE THAN THE FIRE.

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.