Narrative:

I mechanic X was about to service an aircraft with [engine] oil when the crew lead asked me to help a co-worker in the deferral action of a hydraulic shut-off valve (sov). I approached my fellow mechanic Y; asking what needed to be done. Mechanic Y told me to take off the hydraulic pump from the left engine while she took the parts necessary for the deferral out of the 'fly away' kit. Mechanic Y instructed me to install the blank-off plate in the mount [on the engine accessory case] where the hydraulic pump was installed and to secure it along with cannon plug. After I installed this plate and capped the [hydraulic] quick disconnect outlets; I asked if she needed any further assistance. Mechanic Y replied that all she needed to do was to place the hydraulic pump in the 'fly-away' kit. I proceeded to put my tools and toolbox away. With four minutes left before clock-out time; she approached me asking to sign a job card for the task which I was unaware that existed. I signed the blocks required; but failed to see the part where it mentioned the spline plug being installed before the plate. It was determined that the error was made by an emergency landing that the aircraft had to make at ZZZ1 airport due to the [engine oil] leakage. This is to the best of my knowledge lack of communication between co-workers. I assisted my co-worker by following her instructions; she had the paperwork and failed to inform me about the job card; also failed to provide the parts needed to perform the task. I failed to pay the necessary attention at the end of the day to the job card when filling [out] the [sign-off] blocks. Lack of knowledge and experience was also a factor. I've been employed for several months in this company and have never worked on the engine section of these [crj-700] aircraft. Also mechanic Y explained to me that she has never performed this procedure [either]. Some of these mistakes might have been caused by stress and fatigue because it was at the end of the night and my co-worker expressed to me that these plane had to be at the gate [in a half hour]. [Recommend] better communication between mechanics when working as a team; especially if one joins another in the middle of the task; pay more time and attention to job cards when completing them even under stress.

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Original NASA ASRS Text

Title: Two Line Aircraft Maintenance Technicians (AMTs) report about a company CRJ-700 aircraft that had to divert in flight due to oil quantity loss on Number 1 Engine. They had previously removed the Engine Driven Hydraulic Pump (EDP) on the Accessory Gear Box (AGB) and had been 'pushing' to meet a morning departure schedule.

Narrative: I Mechanic X was about to service an aircraft with [engine] oil when the Crew Lead asked me to help a co-worker in the Deferral Action of a hydraulic Shut-Off Valve (SOV). I approached my fellow Mechanic Y; asking what needed to be done. Mechanic Y told me to take off the hydraulic pump from the left engine while she took the parts necessary for the deferral out of the 'Fly Away' kit. Mechanic Y instructed me to install the Blank-Off Plate in the mount [on the Engine Accessory Case] where the hydraulic pump was installed and to secure it along with Cannon plug. After I installed this plate and capped the [hydraulic] quick disconnect outlets; I asked if she needed any further assistance. Mechanic Y replied that all she needed to do was to place the hydraulic pump in the 'Fly-Away' kit. I proceeded to put my tools and toolbox away. With four minutes left before clock-out time; she approached me asking to sign a Job Card for the task which I was unaware that existed. I signed the blocks required; but failed to see the part where it mentioned the Spline Plug being installed before the plate. It was determined that the error was made by an emergency landing that the aircraft had to make at ZZZ1 airport due to the [engine oil] leakage. This is to the best of my knowledge lack of communication between co-workers. I assisted my co-worker by following her instructions; she had the paperwork and failed to inform me about the Job Card; also failed to provide the parts needed to perform the task. I failed to pay the necessary attention at the end of the day to the Job Card when filling [out] the [sign-off] blocks. Lack of knowledge and experience was also a factor. I've been employed for several months in this company and have never worked on the engine section of these [CRJ-700] aircraft. Also Mechanic Y explained to me that she has never performed this procedure [either]. Some of these mistakes might have been caused by stress and fatigue because it was at the end of the night and my co-worker expressed to me that these plane had to be at the gate [in a half hour]. [Recommend] better communication between mechanics when working as a team; especially if one joins another in the middle of the task; pay more time and attention to Job Cards when completing them even under stress.

Data retrieved from NASA's ASRS site as of July 2013 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.