Narrative:

On apr/xa/01 air carrier aircraft xyz was scheduled for overnight maintenance at ZZZ. An overnight check card was assigned. While performing the scheduled check the mechanic noted 3 first stage fan blades with FOD in the left engine. He reported his findings to me as I was the lead mechanic in charge that evening. I proceeded to look up the allowable damage limits for the first stage fan blades in the JT8D maintenance manual as the MD80 aircraft uses the JT8D-217 engine. Only 1 JT8D maintenance manual exists and is labeled 'JT8D maintenance manual complete/reel 1 of 1.' I printed a copy of the maintenance manual limits and requirements for the mechanic to use for evaluation. 2 of the 3 blades fell in an area requiring a 20 hour fly-back limit. The maintenance supervisor, MD80 technician desk foreman and workload planner were advised of this problem and requirements. The mechanic was able to dress the blade damage in accordance with the JT8D maintenance manual specifications. Logbook entries requiring 20 flight hour fly-back limit and 1 florescent penetrant inspection were made. 2 damage file entries were also made recording this problem with maintenance manual references. The aircraft was released for service later that morning. 5 days later, I was shown a letter informing us of a mistake we had made in gathering our reference materials. The letter stated that the JT8D maintenance manual we used did not apply to the JT8D-217 engine and that the MD80 maintenance manual contained the specifications that we should have used. Applicable damage limits were the same except for a note under inspection check that required a borescope inspection of the 6TH and 7TH stage compressor. This requirement was not part of the JT8D maintenance manual and as a result a borescope inspection was not accomplished. Subsequent inspection found damage requiring engine replacement. In order to prevent future error the JT8D maintenance manual should be relabeled to note the exception of the -217 engine. Callback conversation with reporter revealed the following information: the reporter stated the engine manufacturer's maintenance manual is used for all the carrier's engines except for the JT8D-217 engine. The reporter said no notes are in the engine maintenance manual directing the technician to search the aircraft maintenance manual chapter 72 for the JT8D-217 limits. The reporter said the engine manual reader printer tape was labeled JT8D manual complete reel 1 of 1. The reporter stated the company is now acting on a correction.

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Original NASA ASRS Text

Title: AN MD80 WAS DISPATCHED IN NON COMPLIANCE WITH L ENG FAN BLADE DAMAGE DEFERRED USING THE WRONG MANUAL AUTH CAUSED BY PUB DEFICIENCY.

Narrative: ON APR/XA/01 ACR ACFT XYZ WAS SCHEDULED FOR OVERNIGHT MAINT AT ZZZ. AN OVERNIGHT CHK CARD WAS ASSIGNED. WHILE PERFORMING THE SCHEDULED CHK THE MECH NOTED 3 FIRST STAGE FAN BLADES WITH FOD IN THE L ENG. HE RPTED HIS FINDINGS TO ME AS I WAS THE LEAD MECH IN CHARGE THAT EVENING. I PROCEEDED TO LOOK UP THE ALLOWABLE DAMAGE LIMITS FOR THE FIRST STAGE FAN BLADES IN THE JT8D MAINT MANUAL AS THE MD80 ACFT USES THE JT8D-217 ENG. ONLY 1 JT8D MAINT MANUAL EXISTS AND IS LABELED 'JT8D MAINT MANUAL COMPLETE/REEL 1 OF 1.' I PRINTED A COPY OF THE MAINT MANUAL LIMITS AND REQUIREMENTS FOR THE MECH TO USE FOR EVALUATION. 2 OF THE 3 BLADES FELL IN AN AREA REQUIRING A 20 HR FLY-BACK LIMIT. THE MAINT SUPVR, MD80 TECHNICIAN DESK FOREMAN AND WORKLOAD PLANNER WERE ADVISED OF THIS PROB AND REQUIREMENTS. THE MECH WAS ABLE TO DRESS THE BLADE DAMAGE IN ACCORDANCE WITH THE JT8D MAINT MANUAL SPECS. LOGBOOK ENTRIES REQUIRING 20 FLT HR FLY-BACK LIMIT AND 1 FLORESCENT PENETRANT INSPECTION WERE MADE. 2 DAMAGE FILE ENTRIES WERE ALSO MADE RECORDING THIS PROB WITH MAINT MANUAL REFS. THE ACFT WAS RELEASED FOR SVC LATER THAT MORNING. 5 DAYS LATER, I WAS SHOWN A LETTER INFORMING US OF A MISTAKE WE HAD MADE IN GATHERING OUR REF MATERIALS. THE LETTER STATED THAT THE JT8D MAINT MANUAL WE USED DID NOT APPLY TO THE JT8D-217 ENG AND THAT THE MD80 MAINT MANUAL CONTAINED THE SPECS THAT WE SHOULD HAVE USED. APPLICABLE DAMAGE LIMITS WERE THE SAME EXCEPT FOR A NOTE UNDER INSPECTION CHK THAT REQUIRED A BORESCOPE INSPECTION OF THE 6TH AND 7TH STAGE COMPRESSOR. THIS REQUIREMENT WAS NOT PART OF THE JT8D MAINT MANUAL AND AS A RESULT A BORESCOPE INSPECTION WAS NOT ACCOMPLISHED. SUBSEQUENT INSPECTION FOUND DAMAGE REQUIRING ENG REPLACEMENT. IN ORDER TO PREVENT FUTURE ERROR THE JT8D MAINT MANUAL SHOULD BE RELABELED TO NOTE THE EXCEPTION OF THE -217 ENG. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ENG MANUFACTURER'S MAINT MANUAL IS USED FOR ALL THE CARRIER'S ENGS EXCEPT FOR THE JT8D-217 ENG. THE RPTR SAID NO NOTES ARE IN THE ENG MAINT MANUAL DIRECTING THE TECHNICIAN TO SEARCH THE ACFT MAINT MANUAL CHAPTER 72 FOR THE JT8D-217 LIMITS. THE RPTR SAID THE ENG MANUAL READER PRINTER TAPE WAS LABELED JT8D MANUAL COMPLETE REEL 1 OF 1. THE RPTR STATED THE COMPANY IS NOW ACTING ON A CORRECTION.

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.