Narrative:

Medium large transport X was inbound to dca on the bucko 3 arrival with a clearance to cross druzz at 15000'. Mlt Y at FL200 was swbnd on J6 with a radar handoff to R5 with the xfer of communications completed. At about CA22 I observed the C/a between the 2 aircraft. At about XA23 I turned medium large transport X 15 degrees left to ensure sep. Because of medium large transport X ground speed, the turn was insufficient and sep was lost.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR HAS LESS THAN STANDARD SEPARATION BETWEEN ACR MLG DESCENDING ON ARR ROUTE AND AN ENROUTE MLT.

Narrative: MLG X WAS INBND TO DCA ON THE BUCKO 3 ARR WITH A CLRNC TO CROSS DRUZZ AT 15000'. MLT Y AT FL200 WAS SWBND ON J6 WITH A RADAR HDOF TO R5 WITH THE XFER OF COMS COMPLETED. AT ABOUT CA22 I OBSERVED THE C/A BTWN THE 2 ACFT. AT ABOUT XA23 I TURNED MLG X 15 DEGS LEFT TO ENSURE SEP. BECAUSE OF MLG X GND SPD, THE TURN WAS INSUFFICIENT AND SEP WAS LOST.

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.