Narrative:

At start of wing shift, I was assigned to assist in completing the boroscoping of #2 engine on aircraft. The boroscoping had been started by day shift mechanics. An unknown foreman was discussing a nicked blade with company engineers located in san francisco, ca. It was determined the blade was within limits and the boroscoping continued. There was no paperwork generated on what had been started by day shift or the condition of the blade, only verbal commentary to me. After the boroscoping was completed and the plugs were being installed, a foreign part, not normal with plugs was found and an investigation commenced to determine its origin. It was found to be part of an igniter lead. The engine hot section was scrutinized for missing plugs and safety wire and none located and engine cowling closed. A&P reviewed the paperwork (maintenance manual 72-00-41) and found the job to be complete. The aircraft was taxied to the terminal for outbound trip. Departed at XA36, no leakage was reported by dispatching mechanic. After takeoff the low oil pressure light illuminated and flight crew noted loss of oil quantity and returned to field. During investigation it was learned that the accessory gear box drive cover had been left off. The corrective action was to replace the o-ring on the gear box cover and install same. Also, checked chip detectors and found to be clean. Added 16 quarts of oil. Ran engine at cruise power for 10 mins. Leak checked engine and rechked chip detectors, finding no discrepancies with either. Upon inspection of paperwork, it was discovered there was no TOD (task oriented document) as with other engine types. The only mention of replacing the drive cover was in the middle of MM 72-00- 41 page 206 which refers back to the cover removal procedure. In my opinion, I feel that with such an important procedure, there should be a TOD and specific replacement direction for the accessory gear box cover rather than referring the mechanic back to the removal section of the manual.

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Original NASA ASRS Text

Title: FLC OF MLG ACFT SHUT DOWN 1 ENG DUE TO LOSS OF OIL PRESSURE AND RETURNED TO ORIGINAL ARPT.

Narrative: AT START OF WING SHIFT, I WAS ASSIGNED TO ASSIST IN COMPLETING THE BOROSCOPING OF #2 ENG ON ACFT. THE BOROSCOPING HAD BEEN STARTED BY DAY SHIFT MECHS. AN UNKNOWN FOREMAN WAS DISCUSSING A NICKED BLADE WITH COMPANY ENGINEERS LOCATED IN SAN FRANCISCO, CA. IT WAS DETERMINED THE BLADE WAS WITHIN LIMITS AND THE BOROSCOPING CONTINUED. THERE WAS NO PAPERWORK GENERATED ON WHAT HAD BEEN STARTED BY DAY SHIFT OR THE CONDITION OF THE BLADE, ONLY VERBAL COMMENTARY TO ME. AFTER THE BOROSCOPING WAS COMPLETED AND THE PLUGS WERE BEING INSTALLED, A FOREIGN PART, NOT NORMAL WITH PLUGS WAS FOUND AND AN INVESTIGATION COMMENCED TO DETERMINE ITS ORIGIN. IT WAS FOUND TO BE PART OF AN IGNITER LEAD. THE ENG HOT SECTION WAS SCRUTINIZED FOR MISSING PLUGS AND SAFETY WIRE AND NONE LOCATED AND ENG COWLING CLOSED. A&P REVIEWED THE PAPERWORK (MAINT MANUAL 72-00-41) AND FOUND THE JOB TO BE COMPLETE. THE ACFT WAS TAXIED TO THE TERMINAL FOR OUTBOUND TRIP. DEPARTED AT XA36, NO LEAKAGE WAS RPTED BY DISPATCHING MECH. AFTER TKOF THE LOW OIL PRESSURE LIGHT ILLUMINATED AND FLC NOTED LOSS OF OIL QUANTITY AND RETURNED TO FIELD. DURING INVESTIGATION IT WAS LEARNED THAT THE ACCESSORY GEAR BOX DRIVE COVER HAD BEEN LEFT OFF. THE CORRECTIVE ACTION WAS TO REPLACE THE O-RING ON THE GEAR BOX COVER AND INSTALL SAME. ALSO, CHKED CHIP DETECTORS AND FOUND TO BE CLEAN. ADDED 16 QUARTS OF OIL. RAN ENG AT CRUISE PWR FOR 10 MINS. LEAK CHKED ENG AND RECHKED CHIP DETECTORS, FINDING NO DISCREPANCIES WITH EITHER. UPON INSPECTION OF PAPERWORK, IT WAS DISCOVERED THERE WAS NO TOD (TASK ORIENTED DOCUMENT) AS WITH OTHER ENG TYPES. THE ONLY MENTION OF REPLACING THE DRIVE COVER WAS IN THE MIDDLE OF MM 72-00- 41 PAGE 206 WHICH REFERS BACK TO THE COVER REMOVAL PROC. IN MY OPINION, I FEEL THAT WITH SUCH AN IMPORTANT PROC, THERE SHOULD BE A TOD AND SPECIFIC REPLACEMENT DIRECTION FOR THE ACCESSORY GEAR BOX COVER RATHER THAN REFERRING THE MECH BACK TO THE REMOVAL SECTION OF THE MANUAL.

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.