Narrative:

Taxi after aircraft released from maintenance to location for deice procedures. Initially 2-3 inches of powdered snow on aircraft. Taxi included a check-out of braking action on the runway, which was partially plowed. During high speed taxi, snow departed wings and fuselage. No snow remained after taxi to the deice station. Some snow was apparently ingested by the APU. This caused an automatic-shutdown. The shutdown resulted in an 'APU' status message which would normally require an APU inspection, however, since the crew was aware of the probable snow ingestion and likely starving of APU for air (temporarily), the status message was erased. The ground crew was told to advise the supervising FAA personnel (maintenance), but this did not happen for 3 days. The pilot in the left seat and manipulating the controls was an FAA pilot. Normally this status message would be cleared by maintenance, but the flight crew mistakenly thought that snow was the cause of the automatic-shutdown. The APU later was started per recommended procedures and ran normally. On subsequent flts the APU was unusually noisy and an inspection found foreign object damage due to a duct clamp coming off. Used poor judgement in not having maintenance inspect APU right away. May have already been damaged.

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Original NASA ASRS Text

Title: THE APU AUTO SHUTDOWN. THE FLC CONCLUDED THE AUTO SHUTDOWN WAS A NORMAL RESULT OF SNOW INGESTION. THE CREW ELECTED NOT TO FOLLOW THE REQUIRED PROCS OF HAVING THE APU INSPECTED BY MAINT PRIOR TO STARTING THE APU AFTER AN AUTO SHUTDOWN. THE APU HAD FOREIGN OBJECT DAMAGE DUE TO A DUCT CLAMP COMING OFF.

Narrative: TAXI AFTER ACFT RELEASED FROM MAINT TO LOCATION FOR DEICE PROCS. INITIALLY 2-3 INCHES OF POWDERED SNOW ON ACFT. TAXI INCLUDED A CHK-OUT OF BRAKING ACTION ON THE RWY, WHICH WAS PARTIALLY PLOWED. DURING HIGH SPD TAXI, SNOW DEPARTED WINGS AND FUSELAGE. NO SNOW REMAINED AFTER TAXI TO THE DEICE STATION. SOME SNOW WAS APPARENTLY INGESTED BY THE APU. THIS CAUSED AN AUTO-SHUTDOWN. THE SHUTDOWN RESULTED IN AN 'APU' STATUS MESSAGE WHICH WOULD NORMALLY REQUIRE AN APU INSPECTION, HOWEVER, SINCE THE CREW WAS AWARE OF THE PROBABLE SNOW INGESTION AND LIKELY STARVING OF APU FOR AIR (TEMPORARILY), THE STATUS MESSAGE WAS ERASED. THE GND CREW WAS TOLD TO ADVISE THE SUPERVISING FAA PERSONNEL (MAINT), BUT THIS DID NOT HAPPEN FOR 3 DAYS. THE PLT IN THE L SEAT AND MANIPULATING THE CTLS WAS AN FAA PLT. NORMALLY THIS STATUS MESSAGE WOULD BE CLRED BY MAINT, BUT THE FLC MISTAKENLY THOUGHT THAT SNOW WAS THE CAUSE OF THE AUTO-SHUTDOWN. THE APU LATER WAS STARTED PER RECOMMENDED PROCS AND RAN NORMALLY. ON SUBSEQUENT FLTS THE APU WAS UNUSUALLY NOISY AND AN INSPECTION FOUND FOREIGN OBJECT DAMAGE DUE TO A DUCT CLAMP COMING OFF. USED POOR JUDGEMENT IN NOT HAVING MAINT INSPECT APU RIGHT AWAY. MAY HAVE ALREADY BEEN DAMAGED.

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.