Narrative:

Radar controller verbally coordinated with ZKC for both aircraft. Aircraft #1 was then given an altitude below what was coordinated (FL290 was coordinated but FL260 was issued). Aircraft were in ZKC airspace before conflict alert activated and we were notified. Aircraft #2 was level at FL280.

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Original NASA ASRS Text

Title: ZID ASSOCIATE CTLR OBSERVED OPERROR AT FL280 AS CTLR ASSIGNED ALT DIFFERED FROM COORD ALT WITH ADJACENT ARTCC.

Narrative: RADAR CTLR VERBALLY COORDINATED WITH ZKC FOR BOTH ACFT. ACFT #1 WAS THEN GIVEN AN ALT BELOW WHAT WAS COORDINATED (FL290 WAS COORDINATED BUT FL260 WAS ISSUED). ACFT WERE IN ZKC AIRSPACE BEFORE CONFLICT ALERT ACTIVATED AND WE WERE NOTIFIED. ACFT #2 WAS LEVEL AT FL280.

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.