B777 Undifferentiated or Other Model
Maintenance Powerplant; Maintenance Airframe
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance
General Maintenance Action
Procedure; Human Factors
I just became aware of an investigation involving the Number 1 engine on a B777. I assisted with the buildup of the engine after the engine was air shipped. According to the investigation a B-nut was found loose on one of the PT2 (Pressure Total 2) tube connections.I was sent to this field service on the red eye to help mechanics with the engine change. We arrived around XA:00 [in the morning]. The engine wasn't scheduled to arrive till the afternoon. We went to the hotel around XD:00 and returned to the hangar around XJ:00 [in the afternoon] that day. Later that day we helped unload the engine and transport it to the hangar. We started to build up the engine while still in the shipping stand. I assembled the left side of the fan case and my partner was working on the right hand side. Starting at the top; I installed everything on the left side down to about 8:00 o'clock position on the fan case where the stand interfered with any further work. The local crew was still removing the engine from wing. At this point around [XS:00] we went to the hotel and returned the next morning. Waited till around XK:00 for the crew to hang the new engine. We continued the build as soon as the engine was hung and were able to access the bottom. The PT2 line in question is made up of three sections. Not all of these sections were disassembled for shipping. Without knowing the exact location of the loose B-nut I can't say for certain that it was disconnected for shipping. To the best of my knowledge I connected and secured all the lines that were disturbed on the left side. I recall noticing that not all the PT2 tube B-nuts had provision for safety wire; which was odd since the majority of our PW (Pratt and Whitney) engines PT2 tube connections are safety wired. There was an aircraft inspector present during this time monitoring and checking the work.
Maintenance Technician reported a PT2 (Pressure Total 2) tube 'B' Nut was left loose on a Pratt and Whitney engine for a B777 aircraft.