Narrative:

Numerous departures (XXX airlines) departed rdu (runway 23) making wide left turns climbing to FL230 and above. Traffic was inbound rdu via argal intersection V66 and via oxford intersection V3. A fellow controller passing by declined his break and offered assistance. I glady accepted as it started to get busy. Small transport Z requested clearance and departed runway 1 wbound to clt climbing to 12000'. Small transport Z was given a vector nwbound to remain clear of traffic inbound from the southwest at 4000'. Mlt X was given reroute away from head on air carrier departures via tyi V213 wallo V56 fay-fbg. Gsb echo MOA was active up to FL200 (acrobatic area southeast of rdu southwest to tyi). 2 mlt's were inbound to gsb via rdu heading 090 degrees radar vector clear of traffic and direct gsb, one at 16000' and one at 23000' (mlt Y). All the aircraft being handled at this time, with the exception of a few, were climbing and descending (16 at the time of the incident, probably more before) on a scope with a 60 mi range (diameter). Needless to say, it became very busy and very hectic. Required a considerable amount of coordination and sep. Small transport Z was kept in constant vigilance climbing in the face of air carrier jet departures requiring continual coordination with rdu approach control. During this time I remember saying after turning mlt Y to heading 120 degrees, 'I have a clear shot, I'm descending him to 11000'.' our attention was directed back to small transport Z and mlt Y descended approximately 2 mi in front of mlt X at 16000'. They say the C/a went off, I did not see it.

Google
 

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION WHEN MLT Y IS DESCENDED THROUGH THE ALT OF MLT X WITH INSUFFICIENT LATERAL SEPARATION.

Narrative: NUMEROUS DEPS (XXX AIRLINES) DEPARTED RDU (RWY 23) MAKING WIDE LEFT TURNS CLBING TO FL230 AND ABOVE. TFC WAS INBND RDU VIA ARGAL INTXN V66 AND VIA OXFORD INTXN V3. A FELLOW CTLR PASSING BY DECLINED HIS BREAK AND OFFERED ASSISTANCE. I GLADY ACCEPTED AS IT STARTED TO GET BUSY. SMT Z REQUESTED CLRNC AND DEPARTED RWY 1 WBOUND TO CLT CLBING TO 12000'. SMT Z WAS GIVEN A VECTOR NWBOUND TO REMAIN CLR OF TFC INBND FROM THE SW AT 4000'. MLT X WAS GIVEN REROUTE AWAY FROM HEAD ON ACR DEPS VIA TYI V213 WALLO V56 FAY-FBG. GSB ECHO MOA WAS ACTIVE UP TO FL200 (ACROBATIC AREA SE OF RDU SW TO TYI). 2 MLT'S WERE INBND TO GSB VIA RDU HDG 090 DEGS RADAR VECTOR CLR OF TFC AND DIRECT GSB, ONE AT 16000' AND ONE AT 23000' (MLT Y). ALL THE ACFT BEING HANDLED AT THIS TIME, WITH THE EXCEPTION OF A FEW, WERE CLBING AND DSNDING (16 AT THE TIME OF THE INCIDENT, PROBABLY MORE BEFORE) ON A SCOPE WITH A 60 MI RANGE (DIAMETER). NEEDLESS TO SAY, IT BECAME VERY BUSY AND VERY HECTIC. REQUIRED A CONSIDERABLE AMOUNT OF COORD AND SEP. SMT Z WAS KEPT IN CONSTANT VIGILANCE CLBING IN THE FACE OF ACR JET DEPS REQUIRING CONTINUAL COORD WITH RDU APCH CTL. DURING THIS TIME I REMEMBER SAYING AFTER TURNING MLT Y TO HDG 120 DEGS, 'I HAVE A CLR SHOT, I'M DSNDING HIM TO 11000'.' OUR ATTN WAS DIRECTED BACK TO SMT Z AND MLT Y DSNDED APPROX 2 MI IN FRONT OF MLT X AT 16000'. THEY SAY THE C/A WENT OFF, I DID NOT SEE IT.

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.