Narrative:

DC10-10 aircraft arrived in ZZZ for night layover. Aircraft had an MEL on the #1 engine thrust reverser (T/right) that was worked on here and after troubleshooting and replacing the overpressure shutoff valve the item was repaired and the MEL was cleared/closed. Aircraft departed ZZZ the following nigh on normal revenue flight for ZZZ1. The aircraft flew several legs for three days; [when] during a transit through ZZZ2 station; aircraft line maintenance noticed some sheet metal damage on the upper aft edge of both left and right thrust reverser translating cowl; ring tertiary structure at tab structure. ZZZ2 maintenance accomplished an engineering order (east.O.) temporary repair and dispatched aircraft. Apparently both upper metal inoperative indication tabs were still installed and caused some minor sheet metal damage when the thrust reverser deployed. These two upper tabs may have been overlooked during our reactivation of the thrust reverser prior to troubleshooting in ZZZ. The lower tabs were not installed and I made a mental note of that at the time. These tabs; to the best of my knowledge; are not required to be installed under the MEL reference that was used by ZZZ2 when they originally deferred the T/right. When these tabs were required to be used; all four are installed with the lower being the most visible by a person standing on the ground next to the aircraft. During reactivation of the T/right prior to troubleshooting; not seeing the lower tabs installed was expected and may have caused me to not look at [or] for the upper tabs to see if they were installed.

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Original NASA ASRS Text

Title: A Line Mechanic reports about sheet metal damage to the upper aft edge of both the left and right Thrust Reverser Translating Cowl Ring; Tertiary Structure on # 1 engine. The Thrust Reverser upper Inoperative Indication Tabs were still installed after the thrust reversers had been reactivated on their company DC-10 aircraft.

Narrative: DC10-10 Aircraft arrived in ZZZ for night layover. Aircraft had an MEL on the #1 Engine Thrust Reverser (T/R) that was worked on here and after troubleshooting and replacing the Overpressure Shutoff Valve the item was repaired and the MEL was cleared/closed. Aircraft departed ZZZ the following nigh on normal revenue flight for ZZZ1. The Aircraft flew several legs for three days; [when] during a transit through ZZZ2 station; Aircraft Line Maintenance noticed some sheet metal damage on the upper aft edge of both left and right Thrust Reverser Translating Cowl; Ring Tertiary Structure at Tab structure. ZZZ2 Maintenance accomplished an Engineering Order (E.O.) temporary repair and dispatched aircraft. Apparently both upper metal Inoperative Indication Tabs were still installed and caused some minor sheet metal damage when the thrust reverser deployed. These two upper tabs may have been overlooked during our reactivation of the Thrust Reverser prior to troubleshooting in ZZZ. The Lower Tabs were not installed and I made a mental note of that at the time. These Tabs; to the best of my knowledge; are not required to be installed under the MEL reference that was used by ZZZ2 when they originally deferred the T/R. When these tabs WERE required to be used; all four are installed with the lower being the most visible by a person standing on the ground next to the aircraft. During reactivation of the T/R prior to troubleshooting; not seeing the lower tabs installed was expected and may have caused me to not look at [or] for the upper tabs to see if they were installed.

Data retrieved from NASA's ASRS site as of April 2012 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.