B767-300 and 300 ER
Maintenance Airframe; Maintenance Avionics; Maintenance Repairman; Maintenance Powerplant
Maintenance Avionics 9.5
Distraction; Situational Awareness; Time Pressure; Troubleshooting
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Returned To Departure Airport; General Flight Cancelled / Delayed; General Maintenance Action
Human Factors; Procedure
I was co-signing for a Mechanic that had installed a rack. When checking out the install; I believed it to be good. I missed a connector that was not fully engaged as did the Quality Assurance (QA) Inspector. Due to the circumstances; I personally; time constraints or not; will be more thorough with my inspection of work performed before signing for anyone.
An Avionics Technician was informed a B767-300 aircraft had returned to field (air turnback); after he had co-signed for the work performed by another Mechanic. He had missed a connector that was not fully engaged on an avionics rack.