Narrative:

I observed a beacon code coming up from mexico. I can't recall if it was me or my D side that tracked the aircraft. Apparently what happened was the aircraft was tracked up using his beacon code. Unfortunately there was an aircraft in my sector who also had the same code. When the aircraft was tracked up it stole the data tag from aircraft X and placed it on the one in mexico. Shortly thereafter I go on break without realizing what had happened. So aircraft X continued on to the next sector as a mode C intruder. I suppose if the system is capable of noticing two aircraft have the same beacon code maybe there could be an additional safety measure built in to identify aircraft with the same code within a certain proximity of each other.

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Original NASA ASRS Text

Title: ZAB Controller observes a beacon coded target. Another aircraft in his sector had the same beacon code. The original flight was tracked as a Mode-C intruder.

Narrative: I observed a beacon code coming up from Mexico. I can't recall if it was me or my D side that tracked the aircraft. Apparently what happened was the aircraft was tracked up using his beacon code. Unfortunately there was an aircraft in my sector who also had the same code. When the aircraft was tracked up it stole the data tag from Aircraft X and placed it on the one in Mexico. Shortly thereafter I go on break without realizing what had happened. So Aircraft X continued on to the next sector as a mode C intruder. I suppose if the system is capable of noticing two aircraft have the same beacon code maybe there could be an additional safety measure built in to identify aircraft with the same code within a certain proximity of each other.

Data retrieved from NASA's ASRS site 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.