Airbus 318/319/320/321 Undifferentiated
Maintenance Airframe; Maintenance Powerplant
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Aircraft; Procedure; Human Factors
I am submitting this [report] as informational. [A mechanic said] he has serious concerns about contract maintenance being performed in ZZZZ. He stated the following: that he worked on Aircraft X after it returned to ZZZ after left engine oil loss. He was assigned to investigate the oil loss and discovered the Chip Detector o-ring had been installed incorrectly (when installed incorrectly one can see green indicating improper installation) and when he followed up with [Maintenance Control] he discovered the Chip Detector and o-ring had been serviced in ZZZZ. I asked why is he telling me this so much later after the event and he said 'because it just happened again today on Aircraft Y'. He went on to state: he got involved today on Aircraft Y because ZZZ mechanics were investigating an engine oil leak after the aircraft returned to the airport and it seemed familiar to him. Upon further investigation and experience they found the Oil Filter Drain Plug o-ring improperly installed and once again green was showing. He went on to state the aircraft had the work card performed in station ZZZZ by contract maintenance.According to the ZZZ mechanic; he expressed the contractor in ZZZZ either lacks the training or skill level necessary to safely complete the chip detector cards on Airbus aircraft. He explained the housing is aluminum and that the mechanics in ZZZZ may be applying too much torque to the detector when it is installed in the housing.Ensure training of contract maintenance and FAA oversight of contract maintenance is on par with what is required of [the company] in the United States. He also stated that maybe the contractors are not applying the correct torque due to the specified torque value not being converted correctly.
Airbus A320 Series Technician reported that aircraft maintained by foreign contractor have excessive oil loss due to improper maintenance.