Narrative:

I was working the west arrival position and I had aircraft X on the UJM3 arrival. The west departure controller was working aircraft Y a CRJ200; on the MEM7 departure; vectored on a 270 degree heading. Aircraft X was descending to 8000 ft MSL and aircraft Y was climbing to 7000 ft MSL. As aircraft Y leveled at 7000 ft and aircraft X was descending through 8400 ft; aircraft X reported an RA. I had already issued aircraft X the CRJ2 traffic; but I reissued the traffic and directed aircraft X to maintain 8000 ft when able. I then asked aircraft X if the RA advised him to climb. Aircraft X responded that the RA did advise a climb. At this time; the departure controller advised that aircraft Y also received an RA and descended because of it. There was never less than 1000 ft of vertical separation.

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Original NASA ASRS Text

Title: MEM CTLR DESCRIBED AN EVENT BETWEEN A DESCENDING ARR AND CLIMBING DEP; SEPARATED AS REQUIRED AND ISSUED TFC; BUT BOTH EXPERIENCING TCAS RA.

Narrative: I WAS WORKING THE W ARR POS AND I HAD ACFT X ON THE UJM3 ARR. THE W DEP CTLR WAS WORKING ACFT Y A CRJ200; ON THE MEM7 DEP; VECTORED ON A 270 DEG HDG. ACFT X WAS DSNDING TO 8000 FT MSL AND ACFT Y WAS CLBING TO 7000 FT MSL. AS ACFT Y LEVELED AT 7000 FT AND ACFT X WAS DSNDING THROUGH 8400 FT; ACFT X RPTED AN RA. I HAD ALREADY ISSUED ACFT X THE CRJ2 TFC; BUT I REISSUED THE TFC AND DIRECTED ACFT X TO MAINTAIN 8000 FT WHEN ABLE. I THEN ASKED ACFT X IF THE RA ADVISED HIM TO CLB. ACFT X RESPONDED THAT THE RA DID ADVISE A CLB. AT THIS TIME; THE DEP CTLR ADVISED THAT ACFT Y ALSO RECEIVED AN RA AND DSNDED BECAUSE OF IT. THERE WAS NEVER LESS THAN 1000 FT OF VERT SEPARATION.

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.