Narrative:

I was assigned to work on a crj-700 aircraft that was scheduled for overnight maintenance. I performed a visual inspection of the system number 1 and number 2 hydraulic accumulators and found that they required removal for end cap non-destructive testing (ndt). During removal and reinstallation (right/right); I used shop rags to absorb the hydraulic fluid that normally leaks when this task is performed. When finished I did a thorough inspection for tools and materials. All appeared cleared. I asked a mechanic Y to inspect the aft bay before the 311-door was closed; to 'make sure I didn't leave anything in there.' he performed a visual inspection and declared it clear; he then counter-signed all my work cards.two days later; I was called to the [maintenance] office and shown a picture; taken in ZZZ1 of a shop rag jammed in the rudder pulley system. I have no explanation of 'why.' procedures were followed; other employees performed tasks in the aft bay. None of them carried shop rags; but they had opportunity to see a rag left behind. No one reported anything and all performance testing showed nothing out of the ordinary. I am not certain that I am responsible for this occurrence; but the possibility is there.

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Original NASA ASRS Text

Title: Two Mechanics were informed that a shop rag was found jammed in the Rudder Pulley System in the Aft Equipment Bay of a CRJ-700 aircraft after they both had signed-off for the area to be free of FOD material.

Narrative: I was assigned to work on a CRJ-700 aircraft that was scheduled for overnight maintenance. I performed a Visual Inspection of the System Number 1 and Number 2 Hydraulic Accumulators and found that they required removal for end cap Non-Destructive Testing (NDT). During Removal and Reinstallation (R/R); I used shop rags to absorb the hydraulic fluid that normally leaks when this task is performed. When finished I did a thorough inspection for tools and materials. All appeared cleared. I asked a Mechanic Y to inspect the Aft Bay before the 311-Door was closed; to 'make sure I didn't leave anything in there.' He performed a Visual Inspection and declared it clear; he then counter-signed all my work cards.Two days later; I was called to the [Maintenance] Office and shown a picture; taken in ZZZ1 of a shop rag jammed in the Rudder Pulley System. I have no explanation of 'why.' Procedures were followed; other employees performed tasks in the Aft Bay. None of them carried shop rags; but they had opportunity to see a rag left behind. No one reported anything and all Performance Testing showed nothing out of the ordinary. I am not certain that I am responsible for this occurrence; but the possibility is there.

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.