Narrative:

I and another mechanic were assigned to work on an APU problem on an air carrier large transport. This APU unit was on a placard MEL at the time. Upon reviewing the fmr I ran the APU and found that it did not reach or even exceed the limit of 710 degree C but was running at about 660 degree C with it fully loaded down with packs, pumps and electrical power. I shut the APU down and began to accomplish a special items card and found the fuel cracking pressure to need adjustment as per card. I also replaced the APU load control thermostat and adjusted as per the special items card. Then on starting and running the APU all indications were normal at this time so I removed the placard as per the MEL. At no time was I told or saw in the maintenance manual that this was a mandatory scheduled card in the work package provided to me. It was to my understanding that an 'atbt' is a recommendation and not a mandatory requirement to accomplish. In concern of the written statement for the facted item of the fmr of accomplished atbt with the procedures I took I felt I was accomplishing the atbt within the guidelines of recommendations set out by our maintenance tech services. I researched the card and was not able to find it in the maintenance manual chapter and thought that it was put into the fmr by mistake. I feel that this card as important as it may be that it should have been scheduled and this special items card put with the aircraft work package. This could have been noted as a mandatory fixed item. Then if this couldn't be operated as per the MEL without specifically being accomplished this card that's called out.

Google
 

Original NASA ASRS Text

Title: A AND P (AIRFRAME AND PWR PLANT) MECH FOR ACR FAILS TO CORRECTLY SIGN OFF WORK DONE ON APU.

Narrative: I AND ANOTHER MECH WERE ASSIGNED TO WORK ON AN APU PROBLEM ON AN ACR LGT. THIS APU UNIT WAS ON A PLACARD MEL AT THE TIME. UPON REVIEWING THE FMR I RAN THE APU AND FOUND THAT IT DID NOT REACH OR EVEN EXCEED THE LIMIT OF 710 DEG C BUT WAS RUNNING AT ABOUT 660 DEG C WITH IT FULLY LOADED DOWN WITH PACKS, PUMPS AND ELECTRICAL PWR. I SHUT THE APU DOWN AND BEGAN TO ACCOMPLISH A SPECIAL ITEMS CARD AND FOUND THE FUEL CRACKING PRESSURE TO NEED ADJUSTMENT AS PER CARD. I ALSO REPLACED THE APU LOAD CTL THERMOSTAT AND ADJUSTED AS PER THE SPECIAL ITEMS CARD. THEN ON STARTING AND RUNNING THE APU ALL INDICATIONS WERE NORMAL AT THIS TIME SO I REMOVED THE PLACARD AS PER THE MEL. AT NO TIME WAS I TOLD OR SAW IN THE MAINT MANUAL THAT THIS WAS A MANDATORY SCHEDULED CARD IN THE WORK PACKAGE PROVIDED TO ME. IT WAS TO MY UNDERSTANDING THAT AN 'ATBT' IS A RECOMMENDATION AND NOT A MANDATORY REQUIREMENT TO ACCOMPLISH. IN CONCERN OF THE WRITTEN STATEMENT FOR THE FACTED ITEM OF THE FMR OF ACCOMPLISHED ATBT WITH THE PROCS I TOOK I FELT I WAS ACCOMPLISHING THE ATBT WITHIN THE GUIDELINES OF RECOMMENDATIONS SET OUT BY OUR MAINT TECH SVCS. I RESEARCHED THE CARD AND WAS NOT ABLE TO FIND IT IN THE MAINT MANUAL CHAPTER AND THOUGHT THAT IT WAS PUT INTO THE FMR BY MISTAKE. I FEEL THAT THIS CARD AS IMPORTANT AS IT MAY BE THAT IT SHOULD HAVE BEEN SCHEDULED AND THIS SPECIAL ITEMS CARD PUT WITH THE ACFT WORK PACKAGE. THIS COULD HAVE BEEN NOTED AS A MANDATORY FIXED ITEM. THEN IF THIS COULDN'T BE OPERATED AS PER THE MEL WITHOUT SPECIFICALLY BEING ACCOMPLISHED THIS CARD THAT'S CALLED OUT.

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.