Narrative:

Descending towards destination airport, we attempted to start the APU unsuccessfully. 2ND attempt was successful. Upon transfering packs to APU bleed air source a strong odor of raw fuel filled the cabin and cockpit. I and first officer donned our oxygen masks and executed QRH procedures. Declared an emergency and landed. We turned off the APU and put the packs back on engine bleed air which cleared the smell. After landing crash fire rescue equipment and myself determined we could not see any fuel leaking. Maintenance later found fuel pooled at the bottom of the APU fire containment box. Incidently the same problem seems to have happened on 01/01/fri. Callback conversation with reporter revealed the following information: the reporter stated the strong odor of fuel required the use of oxygen masks in the cockpit. The reporter said it was like someone dumped a bucket of kerosene in the cabin aisle. The reporter stated the APU had been reported in the logbook 4 or 5 times for hard starting and smell or fumes in the cabin. The reporter said a contract mechanic checked the power unit and found fuel pooled in the bottom of the APU shroud. The reporter said the fuel was cleaned up and the auxiliary power was deferred per the MEL. The reporter stated he followed the airplane maintenance history and it was again reported causing fumes or an odor in the cabin.

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Original NASA ASRS Text

Title: A CL65 ON APCH, AT 5000 FT APU STARTED AND PACKS SWITCHED TO APU PNEUMATIC AIR WHEN CABIN FILLED WITH STRONG ODOR OF RAW FUEL.

Narrative: DESCENDING TOWARDS DEST ARPT, WE ATTEMPTED TO START THE APU UNSUCCESSFULLY. 2ND ATTEMPT WAS SUCCESSFUL. UPON TRANSFERING PACKS TO APU BLEED AIR SOURCE A STRONG ODOR OF RAW FUEL FILLED THE CABIN AND COCKPIT. I AND FO DONNED OUR OXYGEN MASKS AND EXECUTED QRH PROCS. DECLARED AN EMER AND LANDED. WE TURNED OFF THE APU AND PUT THE PACKS BACK ON ENG BLEED AIR WHICH CLRED THE SMELL. AFTER LNDG CFR AND MYSELF DETERMINED WE COULD NOT SEE ANY FUEL LEAKING. MAINT LATER FOUND FUEL POOLED AT THE BOTTOM OF THE APU FIRE CONTAINMENT BOX. INCIDENTLY THE SAME PROB SEEMS TO HAVE HAPPENED ON 01/01/FRI. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE STRONG ODOR OF FUEL REQUIRED THE USE OF OXYGEN MASKS IN THE COCKPIT. THE RPTR SAID IT WAS LIKE SOMEONE DUMPED A BUCKET OF KEROSENE IN THE CABIN AISLE. THE RPTR STATED THE APU HAD BEEN RPTED IN THE LOGBOOK 4 OR 5 TIMES FOR HARD STARTING AND SMELL OR FUMES IN THE CABIN. THE RPTR SAID A CONTRACT MECH CHKED THE PWR UNIT AND FOUND FUEL POOLED IN THE BOTTOM OF THE APU SHROUD. THE RPTR SAID THE FUEL WAS CLEANED UP AND THE AUXILIARY PWR WAS DEFERRED PER THE MEL. THE RPTR STATED HE FOLLOWED THE AIRPLANE MAINT HISTORY AND IT WAS AGAIN RPTED CAUSING FUMES OR AN ODOR IN THE CABIN.

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.