Date: 201205
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Light: Daylight
Aircraft: Regional Jet 200 ER/LR (CRJ200)
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Taxi
Aircraft component: Rudder Control System
Reporter organization: Air Carrier
Reporter function: Lead Technician
Reporter qualification: Maintenance Airframe; Maintenance Powerplant
Human factors: Situational Awareness; Distraction; Confusion; Communication Breakdown; Workload
Second reporter function: Technician
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Pre-flight
Result: Flight Crew Returned To Gate; General Maintenance Action
Contributing factors: Chart Or Publication; Aircraft; Company Policy; Weather; Procedure; Manuals; Human Factors; Equipment / Tooling
Primary problem: Human Factors

Narrative: Mechanic X was performing cable tensions on the aileron; rudder and elevators of Aircraft X; a CRJ-200 aircraft. Mechanic Y and Mechanic Z were waiting for Mechanic X to finish Tension Checks before they performed the Function Check of the Rudder Power Control Unit (PCU). Mechanic Y said he was waiting on the rig pins for the Functional Check of the Rudder PCUs; so I; Lead Mechanic X; told Mechanic X that we needed to pin the rudder for the Rudder PCU Task; so we would remove them after completion. (At this time I was going through all the Task Cards to see what needed completion and what was completed before dayshift left at XB:30 pm; there were about 90-Task Cards total). We would not do the Rudder PCU Task card till after lunch (XA:00 pm).I found out from another person four days later that Aircraft X had to return to gate because the rudder would not move. It was determined that the rudder rig pins were left in. After looking at the Rudder PCU Task Card; it was discovered rig pins were not needed; it only called for the Rudder Rig Kit installation. It is not necessary to perform a Travel Check of the rudder after the Rudder PCU Task; so if the pins were left in it would not be known. We do not make a write-up for rig pins being installed due to the fact that Task Cards have a block to sign for the removal of them. However; we sometimes encounter more then one Task Card requiring the same items to be pinned; but there might be three people doing three different tasks; sometimes crossing over into different shifts with turnovers.It should be required that the person installing the rig pins for a specific item make a write-up in our maintenance tracking system stating the pins are installed; regardless if the Task Card has a [sign-off] block for it.


Second narrative: Knowingly left forward and aft Rudder Quadrant rig pins in Aircraft X after finishing Rudder Tension Check Task Card... I and Mechanic Y were both assigned to the same Aircraft X. I was finishing up a Rudder Tension Check Task card late in my shift (day shift). Mechanic Y works Second Shift and was about three hours into his scheduled shift. He had just started setting up for a Rudder Backlash Task Card. At the time I thought his Task Card called for all the rudder quadrant pins to be installed; plus one more in the tail. So as I wrapped up my paperwork I decided to initial the [sign-off] block on the task card where it states to remove all the [rig] pins and check for free rudder movement; thinking when Mechanic Y was finished; he would remove all the rig pins. I found out after I came back from my weekend that he was responsible for only one rig pin; which goes thru the Rudder Limiter in the tail. Mechanic Y did nothing wrong here. Therefore; I thought it was okay to sign-off my Task Card and enter it into our Maintenance Tracking System. As a result; the installed rig pins went unnoticed until Aircraft X was leaving the gate. The flight crew noticed the rudder pedals were in a locked condition. That resulted in the aircraft returning to the gate. Subsequently; Maintenance personnel found the pins still installed in the rudder quadrants.I should have just left the task card [sign-off] block open; where it states to remove all rig pins. I just assumed my co-worker was going to pull the pins when he was finished. This assumption; and by not telling my co-worker a second time about the [rig] pin status before I left for the day; caused this incidental; excessive [high] temperatures.


Synopsis: Two Mechanics and one Lead Mechanic report about their involvement with a CRJ-200 aircraft that returned to the gate after a flight crew noticed the rudder pedals were in a locked condition. The CRJ had just been released from a Heavy Check the day before. Rig pins had not been removed from the rudder pedal quadrants.