Narrative:

Aircraft #1 was a cle departure cleared direct yxu by cle approach due to a need to establish some form of separation with another departure also handed off to me. Aircraft #1 was climbed to 17000 ft upon contact. Controller at adjacent sector called to request aircraft #1 be stopped in climb to 13000 ft for aircraft #2, which was being handed off to me level 14000 ft sebound, landing 7g2 (an airport in close proximity). I complied with the request, amending aircraft #1's climb to 13000 ft and obtained control for lower on aircraft #2 respect aircraft #1. Aircraft #1 was changed over to adjacent sector's frequency. I turned my attention to other matters at hand, including issuing special holding instructions to pit arrs due to aco VOR outage. The data block on aircraft #1 was dropped by me due to clutter upon leaving the confines of my airspace. Later I descended aircraft #2 to 12000 ft without an approved means of separation from aircraft #1. Conflict alert activated with aircraft #2 indicating altitude of 13200 ft and lateral distance approximately 3.9 mi and increasing. No evasive action was taken upon observing that separation was being re-established and that safety was not a factor.

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Original NASA ASRS Text

Title: LOSS OF SEPARATION BTWN A DH8 CLBING TO OR LEVEL AT 13000 FT AND A PA24 DSNDING FROM 14000 FT.

Narrative: ACFT #1 WAS A CLE DEP CLRED DIRECT YXU BY CLE APCH DUE TO A NEED TO ESTABLISH SOME FORM OF SEPARATION WITH ANOTHER DEP ALSO HANDED OFF TO ME. ACFT #1 WAS CLBED TO 17000 FT UPON CONTACT. CTLR AT ADJACENT SECTOR CALLED TO REQUEST ACFT #1 BE STOPPED IN CLB TO 13000 FT FOR ACFT #2, WHICH WAS BEING HANDED OFF TO ME LEVEL 14000 FT SEBOUND, LNDG 7G2 (AN ARPT IN CLOSE PROX). I COMPLIED WITH THE REQUEST, AMENDING ACFT #1'S CLB TO 13000 FT AND OBTAINED CTL FOR LOWER ON ACFT #2 RESPECT ACFT #1. ACFT #1 WAS CHANGED OVER TO ADJACENT SECTOR'S FREQ. I TURNED MY ATTN TO OTHER MATTERS AT HAND, INCLUDING ISSUING SPECIAL HOLDING INSTRUCTIONS TO PIT ARRS DUE TO ACO VOR OUTAGE. THE DATA BLOCK ON ACFT #1 WAS DROPPED BY ME DUE TO CLUTTER UPON LEAVING THE CONFINES OF MY AIRSPACE. LATER I DSNDED ACFT #2 TO 12000 FT WITHOUT AN APPROVED MEANS OF SEPARATION FROM ACFT #1. CONFLICT ALERT ACTIVATED WITH ACFT #2 INDICATING ALT OF 13200 FT AND LATERAL DISTANCE APPROX 3.9 MI AND INCREASING. NO EVASIVE ACTION WAS TAKEN UPON OBSERVING THAT SEPARATION WAS BEING RE-ESTABLISHED AND THAT SAFETY WAS NOT A 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.