Narrative:

A possible loss of separation between 7000 and 8000' with 4 to 5 miles. When climbing aircraft was approximately 8 miles away from level flight aircraft, I told the climbing aircraft to descend to 7000' and to expedite down. Between 4 and 5 miles a possibility of a loss of separation may have occurred.

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Original NASA ASRS Text

Title: CTLR CLIMBED ACFT THROUGH ALT OF ANOTHER ACFT RESULTING IN LOSS OF SEPARATION. OPERATIONAL ERROR.

Narrative: A POSSIBLE LOSS OF SEPARATION BTWN 7000 AND 8000' WITH 4 TO 5 MILES. WHEN CLBING ACFT WAS APPROX 8 MILES AWAY FROM LEVEL FLT ACFT, I TOLD THE CLBING ACFT TO DSND TO 7000' AND TO EXPEDITE DOWN. BTWN 4 AND 5 MILES A POSSIBILITY OF A LOSS OF SEPARATION MAY HAVE OCCURRED.

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.