37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Attributes | |
ACN | 974115 |
Time | |
Date | 201110 |
Local Time Of Day | 1801-2400 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Light | Night |
Aircraft 1 | |
Make Model Name | B777-200 |
Operating Under FAR Part | Part 121 |
Flight Phase | Climb |
Component | |
Aircraft Component | Powerplant Fire/Overheat Warning |
Person 1 | |
Function | Technician |
Qualification | Maintenance Airframe Maintenance Powerplant |
Experience | Maintenance Technician 23 |
Events | |
Anomaly | Aircraft Equipment Problem Critical Deviation - Procedural FAR Deviation - Procedural Maintenance Deviation - Procedural Published Material / Policy |
Narrative:
I was assigned to work a B777-200 aircraft with a left engine gearbox fire/overheat loop issue. Myself and mechanic Y were working together; he did the left side half I did the right side. I installed the loop on the engine with several adel-[type] mount clamps; loosely; to leave movement for adjustment. I made the connections on the forward end of the loop with difficulty due to limited access and small hardware. While installing the rest of the loop frame mount clamps; one clamp proved to be very troublesome; I moved to the aft terminal connections while my partner worked on the problem clamp. I installed the rest of the mount clamps and checked the terminal connections. Then we closed the cowling; did the fire/overheat test which passed; and ran the engine for five minutes with still no faults or messages. I can see how I had not correctly tightened the small terminals screws in fear of snapping them off. And also missed loop frame mounts due to frustrations with various areas of the installation. The [maintenance] manual (M/M) did not list [direct mechanic] to remove the bug or the starter; if they were removed it would have made the procedure easier.
Original NASA ASRS Text
Title: After replacing the left engine Gearbox Fire/Overheat Loop on a B777-200 aircraft; a Mechanic was informed the aircraft returned to the airport.
Narrative: I was assigned to work a B777-200 aircraft with a left engine gearbox fire/overheat loop issue. Myself and Mechanic Y were working together; he did the left side half I did the right side. I installed the loop on the engine with several Adel-[type] mount clamps; loosely; to leave movement for adjustment. I made the connections on the forward end of the loop with difficulty due to limited access and small hardware. While installing the rest of the loop frame mount clamps; one clamp proved to be very troublesome; I moved to the aft terminal connections while my partner worked on the problem clamp. I installed the rest of the mount clamps and checked the terminal connections. Then we closed the cowling; did the Fire/Overheat Test which passed; and ran the engine for five minutes with still no faults or messages. I can see how I had not correctly tightened the small terminals screws in fear of snapping them off. And also missed loop frame mounts due to frustrations with various areas of the installation. The [Maintenance] Manual (M/M) did not list [direct Mechanic] to remove the bug or the starter; if they were removed it would have made the procedure easier.
Data retrieved from NASA's ASRS site as of April 2012 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.