Narrative:

Time on position has been really heavy in our center for a long time. I believe this was a big factor -- just very tired; no doubt fatigue played a big role. Aircraft #1 was level FL310 northbound; aircraft #2 was at FL340 direct tlh. I descended aircraft to FL280. Once I realized they were a conflict; I issued traffic alert; turned and continued descending the aircraft till separation was re-established.

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Original NASA ASRS Text

Title: JAX CTLR EXPERIENCED LTSS AT FL310 WHEN DSNDING ACFT THROUGH OCCUPIED ALT; CITING FATIGUE AND TIME ON POS AS CONTRIBUTORY.

Narrative: TIME ON POS HAS BEEN REALLY HVY IN OUR CTR FOR A LONG TIME. I BELIEVE THIS WAS A BIG FACTOR -- JUST VERY TIRED; NO DOUBT FATIGUE PLAYED A BIG ROLE. ACFT #1 WAS LEVEL FL310 NBOUND; ACFT #2 WAS AT FL340 DIRECT TLH. I DSNDED ACFT TO FL280. ONCE I REALIZED THEY WERE A CONFLICT; I ISSUED TFC ALERT; TURNED AND CONTINUED DSNDING THE ACFT TILL SEPARATION WAS RE-ESTABLISHED.

Data retrieved from NASA's ASRS site as of January 2009 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.