The APU was run when it was placarded inoperative.

Attributes
ACN	275725
Time
Date	199406
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mem
State Reference	TN
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	DC-10 30F
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	climbout : takeoff ground : preflight landing other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 200 flight time total : 9000 flight time type : 4000
ASRS Report	275725
Person 2
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : instrument pilot : atp pilot : commercial pilot : flight engineer
Experience	flight time last 90 days : 50 flight time total : 8000 flight time type : 1500
ASRS Report	275812
Events
Anomaly	aircraft equipment problem : critical non adherence : published procedure non adherence : far non adherence other
Independent Detector	other other : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

APU was placarded inoperative. Captain came on aircraft and initiated start with an inoperative sticker and MEL number posted. This start possibly caused damage to fire bottle from heat from APU causing a thermal discharge of the fire bottle on the #2 engine. It is not conclusive that the damage was caused from this start. Do not ignore MEL inoperative stickers on equipment. If placarded, do not use. Supplemental information from acn 275812: the captain wanted to start the APU due to the heat and humidity. The APU was deferred inoperative due to the APU door not opening. The captain turned on the APU switch and the door open light came on. I said that I would check the APU door to see if it was actually open. The APU inlet door was open. It is the door which activates the APU door open light. The captain started the APU. Maintenance said to sign off the APU. Maintenance at denver discovered that the APU exhaust door was the door in question and it was closed. A fire bottle had overheated and discharged, due to the APU exhaust door being closed during APU operation. This discharge was not indicated in the cockpit and the fire loop tested ok.

Original NASA ASRS Text

Title: THE APU WAS RUN WHEN IT WAS PLACARDED INOP.

Narrative: APU WAS PLACARDED INOP. CAPT CAME ON ACFT AND INITIATED START WITH AN INOP STICKER AND MEL NUMBER POSTED. THIS START POSSIBLY CAUSED DAMAGE TO FIRE BOTTLE FROM HEAT FROM APU CAUSING A THERMAL DISCHARGE OF THE FIRE BOTTLE ON THE #2 ENG. IT IS NOT CONCLUSIVE THAT THE DAMAGE WAS CAUSED FROM THIS START. DO NOT IGNORE MEL INOP STICKERS ON EQUIP. IF PLACARDED, DO NOT USE. SUPPLEMENTAL INFO FROM ACN 275812: THE CAPT WANTED TO START THE APU DUE TO THE HEAT AND HUMIDITY. THE APU WAS DEFERRED INOP DUE TO THE APU DOOR NOT OPENING. THE CAPT TURNED ON THE APU SWITCH AND THE DOOR OPEN LIGHT CAME ON. I SAID THAT I WOULD CHK THE APU DOOR TO SEE IF IT WAS ACTUALLY OPEN. THE APU INLET DOOR WAS OPEN. IT IS THE DOOR WHICH ACTIVATES THE APU DOOR OPEN LIGHT. THE CAPT STARTED THE APU. MAINT SAID TO SIGN OFF THE APU. MAINT AT DENVER DISCOVERED THAT THE APU EXHAUST DOOR WAS THE DOOR IN QUESTION AND IT WAS CLOSED. A FIRE BOTTLE HAD OVERHEATED AND DISCHARGED, DUE TO THE APU EXHAUST DOOR BEING CLOSED DURING APU OP. THIS DISCHARGE WAS NOT INDICATED IN THE COCKPIT AND THE FIRE LOOP TESTED OK.

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.