Narrative:

I assumed the manual position (D37) at XX21Z, after having been briefed on sector status and traffic. This was near the end of a busy afternoon push. I went about catching up on 'loose ends,' dead wood (old tickets), etc. I heard the radar controller issue a couple of vectors, so I turned my attention toward the scope, and after a quick look, did not understand the vectors -- there was no traffic around the vectored aircraft (2 airlines). Then I noticed that the 2 acrs and a GA aircraft were in 'coast tract.' I told the radar man that he was losing beacons and to change the codes on those aircraft. I heard him change a couple of codes and turned my attention away from the radar scope and back to my 'D' side duties. Shortly I heard and recorded a clearance to a G3A to descend to FL410 (he was at FL450, bound for phl). Then the G3A was cleared to maintain FL350 (there was an air carrier X at FL330 and an air carrier Y at FL250 under G3A, this put 3 full data blocks in the same area). Shortly I heard an nzzz call and ask the type of aircraft 'in front at FL390.' I heard no response from the 'right' side and looked over at the scope. Nzzz data block was at least 10 mi west of the bkw VORTAC all alone -- no traffic-- quickly I found nzzz flight ticket in the bay (routed to teb at FL370). Then I looked back at the scope and for the first time saw a limited data tag (code and altitude only) among the 2 acrs and the G3A. I pointed and told the right side that had to be him (nzzz)! On a bad code! The right side told the G3A to climb and maintain FL390 and confirm level. G3A said 'we're through FL380, ya want us to climb?' right side, 'yes' then he told nzzz to squawk the new code and turn right to 180 degrees, then G3A left to 360 degrees. I saw G3A mode C show FL373! Nzzz was at FL370 right under G3A. When nzzz was later cleared on course he said 'that was close.' later the G3A called and said TCASII (40 mi range) showed 100 ft!

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Original NASA ASRS Text

Title: D-SIDE CTLR AT ZDC CONTENDS THAT AN OPERROR AND AN NMAC OCCURRED WHEN THE CODES ASSIGNED TO THE FLTS WERE NOT CHANGED IN A TIMELY MANNER TO CODES THAT ZDC'S HOST COMPUTER WOULD TRACK. DURING THE ATTEMPTED CHANGE, THE RADAR CTLR LOST TRACK OF THE FLTS AND SUBSEQUENTLY AN INCIDENT HAPPENED.

Narrative: I ASSUMED THE MANUAL POS (D37) AT XX21Z, AFTER HAVING BEEN BRIEFED ON SECTOR STATUS AND TFC. THIS WAS NEAR THE END OF A BUSY AFTERNOON PUSH. I WENT ABOUT CATCHING UP ON 'LOOSE ENDS,' DEAD WOOD (OLD TICKETS), ETC. I HEARD THE RADAR CTLR ISSUE A COUPLE OF VECTORS, SO I TURNED MY ATTN TOWARD THE SCOPE, AND AFTER A QUICK LOOK, DID NOT UNDERSTAND THE VECTORS -- THERE WAS NO TFC AROUND THE VECTORED ACFT (2 AIRLINES). THEN I NOTICED THAT THE 2 ACRS AND A GA ACFT WERE IN 'COAST TRACT.' I TOLD THE RADAR MAN THAT HE WAS LOSING BEACONS AND TO CHANGE THE CODES ON THOSE ACFT. I HEARD HIM CHANGE A COUPLE OF CODES AND TURNED MY ATTN AWAY FROM THE RADAR SCOPE AND BACK TO MY 'D' SIDE DUTIES. SHORTLY I HEARD AND RECORDED A CLRNC TO A G3A TO DSND TO FL410 (HE WAS AT FL450, BOUND FOR PHL). THEN THE G3A WAS CLRED TO MAINTAIN FL350 (THERE WAS AN ACR X AT FL330 AND AN ACR Y AT FL250 UNDER G3A, THIS PUT 3 FULL DATA BLOCKS IN THE SAME AREA). SHORTLY I HEARD AN NZZZ CALL AND ASK THE TYPE OF ACFT 'IN FRONT AT FL390.' I HEARD NO RESPONSE FROM THE 'R' SIDE AND LOOKED OVER AT THE SCOPE. NZZZ DATA BLOCK WAS AT LEAST 10 MI W OF THE BKW VORTAC ALL ALONE -- NO TFC-- QUICKLY I FOUND NZZZ FLT TICKET IN THE BAY (ROUTED TO TEB AT FL370). THEN I LOOKED BACK AT THE SCOPE AND FOR THE FIRST TIME SAW A LIMITED DATA TAG (CODE AND ALT ONLY) AMONG THE 2 ACRS AND THE G3A. I POINTED AND TOLD THE R SIDE THAT HAD TO BE HIM (NZZZ)! ON A BAD CODE! THE R SIDE TOLD THE G3A TO CLB AND MAINTAIN FL390 AND CONFIRM LEVEL. G3A SAID 'WE'RE THROUGH FL380, YA WANT US TO CLB?' R SIDE, 'YES' THEN HE TOLD NZZZ TO SQUAWK THE NEW CODE AND TURN R TO 180 DEGS, THEN G3A L TO 360 DEGS. I SAW G3A MODE C SHOW FL373! NZZZ WAS AT FL370 RIGHT UNDER G3A. WHEN NZZZ WAS LATER CLRED ON COURSE HE SAID 'THAT WAS CLOSE.' LATER THE G3A CALLED AND SAID TCASII (40 MI RANGE) SHOWED 100 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.