Narrative:

Atx X was climbing out on arwys when he reported a near miss with unidented aircraft Y. The pilot did not say if he took any evasive action. At this same time, I was working other traffic inbound to the airport as well as identing a call up south of the airport. After the incident was reported, the unidented aircraft appeared to be changing altitudes as if to be flying above or below clouds. Additionally, when the pilot reported the incident, I then observed the traffic a mi to the left of atx X at about the same altitude flying same direction.

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Original NASA ASRS Text

Title: NMAC BETWEEN ATX AND UNKNOWN ACFT.

Narrative: ATX X WAS CLBING OUT ON ARWYS WHEN HE RPTED A NEAR MISS WITH UNIDENTED ACFT Y. THE PLT DID NOT SAY IF HE TOOK ANY EVASIVE ACTION. AT THIS SAME TIME, I WAS WORKING OTHER TFC INBND TO THE ARPT AS WELL AS IDENTING A CALL UP S OF THE ARPT. AFTER THE INCIDENT WAS RPTED, THE UNIDENTED ACFT APPEARED TO BE CHANGING ALTS AS IF TO BE FLYING ABOVE OR BELOW CLOUDS. ADDITIONALLY, WHEN THE PLT RPTED THE INCIDENT, I THEN OBSERVED THE TFC A MI TO THE LEFT OF ATX X AT ABOUT THE SAME ALT FLYING SAME DIRECTION.

Data retrieved from NASA's ASRS site as of August 2007 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.