Narrative:

During preflts, flight attendant/pilot briefing in progress in the first class cabin. Aircraft ground power was lost. When I went to the cockpit to investigate, I found all APU fire warnings, bells and lights activated. The APU had automatically shut down and the APU fire bottle had automatically discharged. I ordered the flight attendants off the aircraft (no passenger were on board). I called ewr ground control and called for fire truck/crash fire rescue equipment assistance. I informed them the aircraft was empty and I could not see the tail of the aircraft. Subsequent maintenance investigation found no evidence of fire. Possible computer card fault or APU fault. Aircraft was subsequently redispatched with APU inoperative and APU fire bottle discharged per MEL. ETOPS flight plan changed from 180 mins to 120 mins.

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Original NASA ASRS Text

Title: B777-200 CREW HAD AN APU FIRE WARNING WHICH RESULTED IN AN APU AUTO SHUTDOWN AND AN AUTO AGENT DISCHARGE.

Narrative: DURING PREFLTS, FLT ATTENDANT/PLT BRIEFING IN PROGRESS IN THE FIRST CLASS CABIN. ACFT GND PWR WAS LOST. WHEN I WENT TO THE COCKPIT TO INVESTIGATE, I FOUND ALL APU FIRE WARNINGS, BELLS AND LIGHTS ACTIVATED. THE APU HAD AUTOMATICALLY SHUT DOWN AND THE APU FIRE BOTTLE HAD AUTOMATICALLY DISCHARGED. I ORDERED THE FLT ATTENDANTS OFF THE ACFT (NO PAX WERE ON BOARD). I CALLED EWR GND CTL AND CALLED FOR FIRE TRUCK/CFR ASSISTANCE. I INFORMED THEM THE ACFT WAS EMPTY AND I COULD NOT SEE THE TAIL OF THE ACFT. SUBSEQUENT MAINT INVESTIGATION FOUND NO EVIDENCE OF FIRE. POSSIBLE COMPUTER CARD FAULT OR APU FAULT. ACFT WAS SUBSEQUENTLY REDISPATCHED WITH APU INOP AND APU FIRE BOTTLE DISCHARGED PER MEL. ETOPS FLT PLAN CHANGED FROM 180 MINS TO 120 MINS.

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.