Narrative:

ZFW passed inbound to sjt approach on atx X deviating around thunderstorms at 8000'. Atx Y departed sjt, climbing to 7000'. ZFW advised that atx X was at 6700'. ZFW also wanted to know if sjt approach was talking to the aircraft. Sjt was not at that time. Within 15 seconds, atx X called me and said he was out of 6700'. Sjt approach then asked atx X to say again his assigned altitude and present altitude. Atx X responded 6300', and then said he was level 8000'. At that point, atx Y and atx X had each other in sight and I gave visibility climb and descent. Atx Y told sjt approach that atx X had passed just under him and was not at 8000' as the pilot had said, but in fact at 6100'.

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Original NASA ASRS Text

Title: ATX CAME IN CLOSE PROX TO OPPOSITE DIRECTION TRAFFIC.

Narrative: ZFW PASSED INBND TO SJT APCH ON ATX X DEVIATING AROUND TSTMS AT 8000'. ATX Y DEPARTED SJT, CLBING TO 7000'. ZFW ADVISED THAT ATX X WAS AT 6700'. ZFW ALSO WANTED TO KNOW IF SJT APCH WAS TALKING TO THE ACFT. SJT WAS NOT AT THAT TIME. WITHIN 15 SECS, ATX X CALLED ME AND SAID HE WAS OUT OF 6700'. SJT APCH THEN ASKED ATX X TO SAY AGAIN HIS ASSIGNED ALT AND PRESENT ALT. ATX X RESPONDED 6300', AND THEN SAID HE WAS LEVEL 8000'. AT THAT POINT, ATX Y AND ATX X HAD EACH OTHER IN SIGHT AND I GAVE VIS CLB AND DSCNT. ATX Y TOLD SJT APCH THAT ATX X HAD PASSED JUST UNDER HIM AND WAS NOT AT 8000' AS THE PLT HAD SAID, BUT IN FACT AT 6100'.

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.