Narrative:

On jul/xx/97 I was assigned to the aircraft. I had taken the job of replacing the vscf (backup generator) due to the failure of the oil quantity switch. I went and printed copies of the removal and installation maintenance manual and received the part from stores that had been ordered for the aircraft by either maintenance or one of our material distributors and placed in stash. At this point, I am not 100% sure if the part was a svcable unit or a robbed unit from another aircraft the part number that was on the deferral was correct but the part received was not for the aircraft confign. Following the procedures in the maintenance manual I removed and started installation of the unit. At this point I was removed from the job and asked to run an airplane for another maintenance crew. Other members of the crew completed installation of the unit for me. Approximately 3 weeks later, our materials records department found that the wrong confign unit had been installed on the aircraft. The unit was then checked and replaced by another station without incident. I feel that my complacency of others ordering my parts for me had caused me to not verify that it was the correct part. Also, my over eagerness to work on this type may have also been a contributing factor in my judgement. Callback conversation with reporter revealed the following information: reporter stated that the maintenance manual was not specific enough on the 2 types of variable speed constant frequency AC backup power units for the 2 models of B777 aircraft. However, the illustrated parts catalog clearly noted the 2 types. The reporter advised that the unit was ordered by another company maintenance organization and was on the job when work started. Operational check was ok after installation. The reporter stated the FAA has made no contact.

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Original NASA ASRS Text

Title: A B777 WAS DISPATCHED WITH THE INCORRECT R ENG VARIABLE SPD CONSTANT FREQ AC BACKUP GENERATOR INSTALLED.

Narrative: ON JUL/XX/97 I WAS ASSIGNED TO THE ACFT. I HAD TAKEN THE JOB OF REPLACING THE VSCF (BACKUP GENERATOR) DUE TO THE FAILURE OF THE OIL QUANTITY SWITCH. I WENT AND PRINTED COPIES OF THE REMOVAL AND INSTALLATION MAINT MANUAL AND RECEIVED THE PART FROM STORES THAT HAD BEEN ORDERED FOR THE ACFT BY EITHER MAINT OR ONE OF OUR MATERIAL DISTRIBUTORS AND PLACED IN STASH. AT THIS POINT, I AM NOT 100% SURE IF THE PART WAS A SVCABLE UNIT OR A ROBBED UNIT FROM ANOTHER ACFT THE PART NUMBER THAT WAS ON THE DEFERRAL WAS CORRECT BUT THE PART RECEIVED WAS NOT FOR THE ACFT CONFIGN. FOLLOWING THE PROCS IN THE MAINT MANUAL I REMOVED AND STARTED INSTALLATION OF THE UNIT. AT THIS POINT I WAS REMOVED FROM THE JOB AND ASKED TO RUN AN AIRPLANE FOR ANOTHER MAINT CREW. OTHER MEMBERS OF THE CREW COMPLETED INSTALLATION OF THE UNIT FOR ME. APPROX 3 WKS LATER, OUR MATERIALS RECORDS DEPT FOUND THAT THE WRONG CONFIGN UNIT HAD BEEN INSTALLED ON THE ACFT. THE UNIT WAS THEN CHKED AND REPLACED BY ANOTHER STATION WITHOUT INCIDENT. I FEEL THAT MY COMPLACENCY OF OTHERS ORDERING MY PARTS FOR ME HAD CAUSED ME TO NOT VERIFY THAT IT WAS THE CORRECT PART. ALSO, MY OVER EAGERNESS TO WORK ON THIS TYPE MAY HAVE ALSO BEEN A CONTRIBUTING FACTOR IN MY JUDGEMENT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THE MAINT MANUAL WAS NOT SPECIFIC ENOUGH ON THE 2 TYPES OF VARIABLE SPD CONSTANT FREQ AC BACKUP PWR UNITS FOR THE 2 MODELS OF B777 ACFT. HOWEVER, THE ILLUSTRATED PARTS CATALOG CLRLY NOTED THE 2 TYPES. THE RPTR ADVISED THAT THE UNIT WAS ORDERED BY ANOTHER COMPANY MAINT ORGANIZATION AND WAS ON THE JOB WHEN WORK STARTED. OPERATIONAL CHK WAS OK AFTER INSTALLATION. THE RPTR STATED THE FAA HAS MADE NO CONTACT.

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.