Narrative:

I returned to sector from break. Sector was much too busy. I plugged into D side, called ZOB air hi sector and mgw low sector, and asked them to hold the rest of the inbound traffic until we got things worked out. Just after that the 'right' controller descended air carrier X through air carrier Y. Both aircraft on vectors multiple data block overlaps. It now seems to be policy to staff to 1 man sectors but workload changes faster than help can become available. Supplemental information from acn 251805: I was working an arrival sector that feeds iad Z. Iad Z had requested 20 mi in trail to dca. I had 5 aircraft to dca strung out but the first 3 were only separated by 10 mi. I took the second aircraft, air carrier X at 16000 ft, and gave him a 360 degree turn. I then was vectoring behind the first arrival to get 20 mi in trail. While all this was happening, I had 3 more arrs to bwi that were deviating for WX. 3 more propellers inbound to dulles. An overflt landing mdt. A departure climbing into all the other traffic. But my main concern is I didn't have any help! My supervisor, prior to this happening, had said that I needed help. He never did anything about it. Only when I started shouting 'this isn't working' did he start to try and get me some help. It was way too late. Air carrier X was heading 270 degrees away from the arrival fix and the air carrier Y jet was being vectored back on course to be #2 in the sequence. Air carrier X was descended to 15000 ft, conflict alert activated but by the time I saw it, separation was lost (approximately 3.5 mi, 500 ft).

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Original NASA ASRS Text

Title: ACR X DSCNT TO OCCUPIED ALT HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: I RETURNED TO SECTOR FROM BREAK. SECTOR WAS MUCH TOO BUSY. I PLUGGED INTO D SIDE, CALLED ZOB AIR HI SECTOR AND MGW LOW SECTOR, AND ASKED THEM TO HOLD THE REST OF THE INBOUND TFC UNTIL WE GOT THINGS WORKED OUT. JUST AFTER THAT THE 'R' CTLR DSNDED ACR X THROUGH ACR Y. BOTH ACFT ON VECTORS MULTIPLE DATA BLOCK OVERLAPS. IT NOW SEEMS TO BE POLICY TO STAFF TO 1 MAN SECTORS BUT WORKLOAD CHANGES FASTER THAN HELP CAN BECOME AVAILABLE. SUPPLEMENTAL INFO FROM ACN 251805: I WAS WORKING AN ARR SECTOR THAT FEEDS IAD Z. IAD Z HAD REQUESTED 20 MI IN TRAIL TO DCA. I HAD 5 ACFT TO DCA STRUNG OUT BUT THE FIRST 3 WERE ONLY SEPARATED BY 10 MI. I TOOK THE SECOND ACFT, ACR X AT 16000 FT, AND GAVE HIM A 360 DEG TURN. I THEN WAS VECTORING BEHIND THE FIRST ARR TO GET 20 MI IN TRAIL. WHILE ALL THIS WAS HAPPENING, I HAD 3 MORE ARRS TO BWI THAT WERE DEVIATING FOR WX. 3 MORE PROPS INBOUND TO DULLES. AN OVERFLT LNDG MDT. A DEP CLBING INTO ALL THE OTHER TFC. BUT MY MAIN CONCERN IS I DIDN'T HAVE ANY HELP! MY SUPVR, PRIOR TO THIS HAPPENING, HAD SAID THAT I NEEDED HELP. HE NEVER DID ANYTHING ABOUT IT. ONLY WHEN I STARTED SHOUTING 'THIS ISN'T WORKING' DID HE START TO TRY AND GET ME SOME HELP. IT WAS WAY TOO LATE. ACR X WAS HDG 270 DEGS AWAY FROM THE ARR FIX AND THE ACR Y JET WAS BEING VECTORED BACK ON COURSE TO BE #2 IN THE SEQUENCE. ACR X WAS DSNDED TO 15000 FT, CONFLICT ALERT ACTIVATED BUT BY THE TIME I SAW IT, SEPARATION WAS LOST (APPROX 3.5 MI, 500 FT).

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.