Narrative:

Mlt X wbound 310, large transport Y nebound 250 (60 mi apart at this point) mlt X descended to 250 air carrier jet same direction just below at 240 descending. Mlt X turned to 220 degree heading to vector south of day inbound (air carrier). Air carrier left 240, mlt X was then cleared 240 and direct ffo (approximately 275 degree heading) which put him in confliction with large transport Y, unnoticed at this point. Conflict alert activated mlt X was turned to 180 degree heading. Large transport Y was turned to 360 degree heading, but did not respond. Mlt X was then descended 220. Traffic was called. Mlt X reported traffic in sight and leaving 235. Mlt X was then switched to low sector frequency. Ape hi sector working 20 aircraft (very complex), weather no factor, a slow moving small transport at FL250 in to cross over the top at 249 to cle, and pit inbounds northeast corner of sector caused several climbers to be stopped at 240 forcing inbounds over top of cle. This situation may have diverted my attention from mlt X. Callback conversation with reporter revealed the following information: reporter gave type aircraft involved and proximity of traffic. Also specified the location of the incident as 30 southwest ape. Sector was fully staffed with D controller and tracker. Traffic volume was heavy and slow moving small transport in high altitude structure was creating more workload and very distracting.

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Original NASA ASRS Text

Title: ARTCC CTLR HAD LESS THAN STANDARD SEPARATION BETWEEN MLT DESCENDING THROUGH ALT OF ENROUTE LGT.

Narrative: MLT X WBOUND 310, LGT Y NEBOUND 250 (60 MI APART AT THIS POINT) MLT X DESCENDED TO 250 ACR JET SAME DIRECTION JUST BELOW AT 240 DESCENDING. MLT X TURNED TO 220 DEG HEADING TO VECTOR SOUTH OF DAY INBOUND (ACR). ACR LEFT 240, MLT X WAS THEN CLRED 240 AND DIRECT FFO (APPROX 275 DEG HEADING) WHICH PUT HIM IN CONFLICTION WITH LGT Y, UNNOTICED AT THIS POINT. CONFLICT ALERT ACTIVATED MLT X WAS TURNED TO 180 DEG HEADING. LGT Y WAS TURNED TO 360 DEG HEADING, BUT DID NOT RESPOND. MLT X WAS THEN DESCENDED 220. TFC WAS CALLED. MLT X REPORTED TFC IN SIGHT AND LEAVING 235. MLT X WAS THEN SWITCHED TO LOW SECTOR FREQ. APE HI SECTOR WORKING 20 ACFT (VERY COMPLEX), WEATHER NO FACTOR, A SLOW MOVING SMT AT FL250 IN TO CROSS OVER THE TOP AT 249 TO CLE, AND PIT INBOUNDS NE CORNER OF SECTOR CAUSED SEVERAL CLIMBERS TO BE STOPPED AT 240 FORCING INBOUNDS OVER TOP OF CLE. THIS SITUATION MAY HAVE DIVERTED MY ATTN FROM MLT X. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING INFORMATION: REPORTER GAVE TYPE ACFT INVOLVED AND PROX OF TFC. ALSO SPECIFIED THE LOCATION OF THE INCIDENT AS 30 SW APE. SECTOR WAS FULLY STAFFED WITH D CTLR AND TRACKER. TFC VOLUME WAS HEAVY AND SLOW MOVING SMT IN HIGH ALT STRUCTURE WAS CREATING MORE WORKLOAD AND VERY DISTRACTING.

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.