Commercial Fixed Wing
Distraction; Fatigue; Time Pressure
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors; Staffing; Weather
We had Aircraft X in ZZZ. When receiving the package; we realize there was a lot of work involved on the aircraft. There's a borescope number one engine; a bleed check number one engine and to open up number two engine to retrieve a broken borescope stem inside the motor and also a Transit Inspection Check. [Person #1] worked the borescope on number one engine; [Person #2] worked the bleed check on number one engine; and I was to retrieve the broken borescope stem T1/2 and number to motor.After opening up number two engine fan cowls and c ducts; I proceeded to install the HCU (Hydraulic Control Unit) lockout pin for safety for operation of the TR (Thrust Reverser) sleeves. After a long night of high winds blowing dust; we [were] ready to close the aircraft up at XA:00 AM in the morning. I closed the c ducts on number 2 engine and close the fan cowls and secured them. The wind must have blown the HCU [lockout pin] painted red streamer up into the motor where I did not see it when I closed the fan cowls. It was a long night with abnormal working conditions and the heavy workload. When I woke up at noon; I contacted my Manager to let him know what had happened and he called Maintenance Operations to let them know what had happened.
Maintenance Technician reported that after inspecting engine; he left the lock out pin red streamer in engine compartment.