Emergency in flight, APU startup on approach (checklist item), over temperature, then fire light and...

Attributes
ACN	108096
Time
Date	198904
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : psp
State Reference	CA
Altitude	msl bound lower : 6000 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : psp
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 150 flight time total : 3800 flight time type : 200
ASRS Report	108096
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 170 flight time total : 4200 flight time type : 500
ASRS Report	107850
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : declared emergency flight crew : overcame equipment problem
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

We were on a visibility approach for psp, runway 30, right downwind, descending through 6000' and 210 KTS when I (copilot) activated the APU (final item on descent checklist). The light off on the start seemed to have a normal temperature acceleration momentarily, then the gauge pegged to 730 degrees C, a hot start, but within starting limits. A low oil pressure light was also initially observed momentarily, however it extinguished after a second. 2 or 3 seconds after the RPM and temperature of the APU had stabilized we got an APU fire light and bell. I then proceeded with our emergency drill for APU fire, by shutting off the APU and pressing the APU fire extinguisher switch. The fire light went out. We then proceeded with the abnormal checklist and completed that on final approach. The captain called the tower for fire trucks to standby and notified the F/a's of our problem. After T/D the fire trucks observed the aircraft externally and reported no fire or smoke visible from the tail. After the passenger were deboarded, the mechanics determined the likely cause of the fire was a fuel line leak.

Original NASA ASRS Text

Title: EMERGENCY IN FLT, APU STARTUP ON APCH (CHECKLIST ITEM), OVER TEMPERATURE, THEN FIRE LIGHT AND WARNING BELL.

Narrative: WE WERE ON A VIS APCH FOR PSP, RWY 30, RIGHT DOWNWIND, DSNDING THROUGH 6000' AND 210 KTS WHEN I (COPLT) ACTIVATED THE APU (FINAL ITEM ON DSCNT CHKLIST). THE LIGHT OFF ON THE START SEEMED TO HAVE A NORMAL TEMP ACCELERATION MOMENTARILY, THEN THE GAUGE PEGGED TO 730 DEGS C, A HOT START, BUT WITHIN STARTING LIMITS. A LOW OIL PRESSURE LIGHT WAS ALSO INITIALLY OBSERVED MOMENTARILY, HOWEVER IT EXTINGUISHED AFTER A SECOND. 2 OR 3 SECS AFTER THE RPM AND TEMP OF THE APU HAD STABILIZED WE GOT AN APU FIRE LIGHT AND BELL. I THEN PROCEEDED WITH OUR EMER DRILL FOR APU FIRE, BY SHUTTING OFF THE APU AND PRESSING THE APU FIRE EXTINGUISHER SWITCH. THE FIRE LIGHT WENT OUT. WE THEN PROCEEDED WITH THE ABNORMAL CHKLIST AND COMPLETED THAT ON FINAL APCH. THE CAPT CALLED THE TWR FOR FIRE TRUCKS TO STANDBY AND NOTIFIED THE F/A'S OF OUR PROB. AFTER T/D THE FIRE TRUCKS OBSERVED THE ACFT EXTERNALLY AND RPTED NO FIRE OR SMOKE VISIBLE FROM THE TAIL. AFTER THE PAX WERE DEBOARDED, THE MECHS DETERMINED THE LIKELY CAUSE OF THE FIRE WAS A FUEL LINE LEAK.

Data retrieved from NASA's ASRS site as of August 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.

Emergency in flight, APU startup on approach (checklist item), over temperature, then fire light and warning bell.