Narrative:

1 aircraft (X) at FL280, crossing under traffic at FL290 (Y). Aircraft at FL280, filed for FL350, was about to enter another center. FL310 was requested and approved. Controller came back from land line call and climbed lower aircraft without consideration for higher. Possible distraction to resolve this conflict and move to other sits only contributing factor.

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Original NASA ASRS Text

Title: CTLR FORGETS ABOUT HIGHER TFC AND CLBS AN ACR THROUGH OCCUPIED ALT. LOSS OF SEPARATION OCCURRED.

Narrative: 1 ACFT (X) AT FL280, XING UNDER TFC AT FL290 (Y). ACFT AT FL280, FILED FOR FL350, WAS ABOUT TO ENTER ANOTHER CTR. FL310 WAS REQUESTED AND APPROVED. CTLR CAME BACK FROM LAND LINE CALL AND CLBED LOWER ACFT WITHOUT CONSIDERATION FOR HIGHER. POSSIBLE DISTR TO RESOLVE THIS CONFLICT AND MOVE TO OTHER SITS ONLY CONTRIBUTING FACTOR.

Data retrieved from NASA's ASRS site as of July 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.