EMB ERJ 170/175 ER/LR
Maintenance Airframe; Maintenance Powerplant
Situational Awareness; Troubleshooting
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Maintenance
Flight Crew Overcame Equipment Problem; General Flight Cancelled / Delayed; General Maintenance Action
Procedure; Human Factors; Aircraft
I was informed by my supervisor that an aircraft I worked on as an inspector had a #1 Engine [Vibration] Amber during climb. Pilot ran QRH and after 5 min. amber went away. Message came up again in cruise. Pilot ran QRH again after power reduction. We sent a crew of 2 for a road trip to address the issue along with what looks like had a bird strike event on said engine. The corrective action was that they found engine fan blades 21 and 23 on left engine to have bumpers missing and found later at the units hub.On my first day of the week on ZZZ Company hangar; I was informed by the supervisor that we had an aircraft with a dual engine blade and blade pin replacement due to flight crew reporting L/H (left hand) engine amber LP (Low Pressure) vibration of 4.0 on climb. I was the inspector on duty. When I got to work; all engine blades and pins had been removed. They had one mechanic per each engine and I was the inspector for both. We performed all maintenance IAW (in accordance with) ST Cards and maintenance manuals as required. I was there for the installation of all blades from start to finish; including bumper gap inspection.I am submitting this report in case of an assumption that we might have deviated from any maintenance procedure. We did not. This is a way for me to tell my side of the situation. Like I said I was there for all the installation process and I believe that if somehow the bumpers where incorrectly installed it would have reflected on the blade gap checks and at the time they were all within engine specs. It is also important to notice that said aircraft had a bird strike ingestion event resulting in some blade damage on said engine location. I hope this information helps. Thank you.
Inspector reported two fan blade bumpers were left out after reinstalling the left hand engine fan blades after routine maintenance. This caused excessive vibration on the left hand engine on climb out.