Narrative:

Air carrier X (M82) at FL310 swbnd overtaking air carrier Z (M78) at FL310 over norfolk and air carrier X was crossing with a corp jet at FL310 west of norfolk 8 mi southbound to dixon VORTAC. The salisbury high controller descended air carrier X to FL280 after coordinating with us and after he realized he was giving us a pair of FL310's. We could not see the altitude on northbound air carrier Y because the data tag was overlapped with a passing aircraft. Traffic conditions were moderate-heavy with OJT on radar in progress. 2 other aircraft were on vectors for WX and traffic at the time. When we moved the data tag on air carrier Y and the tag of air carrier X who was now also overlapping passing traffic, I saw the confliction and gave immediate turns to both and called traffic to both pilots who reported seeing each other. Aircraft passed approximately 1 mi and approximately 500'. Other: similar call signs, OJT on radar in progress, WX deviations, corp jet at FL310 real slow with numerous other aircraft at FL310 during moderate-heavy traffic conditions. Another corp at FL260 swbnd across washington and baltimore departure path climbing to FL260. Air carrier X at M82 overtaking air carrier Z at M78 both at FL310. Air carrier Y northbound at FL290 data tag overlapped with another passing aircraft. Supplemental information from acn 93112: we were cruising at FL310 and were advised that we were overtaking slower traffic. We were given descent clearance to FL280. ATC changed us to another frequency and we were given an immediate left turn. I stopped the descent at 29600' while initiating a 30 degree bank left turn. The on-coming traffic was at FL290 on the same frequency. He initiated a left turn also. We both then had each other visually, 600' vertical, 1/2 mi horizontal. Better ATC coordination was needed in this case.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN 2 ACR. OPERATIONAL ERROR.

Narrative: ACR X (M82) AT FL310 SWBND OVERTAKING ACR Z (M78) AT FL310 OVER NORFOLK AND ACR X WAS XING WITH A CORP JET AT FL310 W OF NORFOLK 8 MI SBND TO DIXON VORTAC. THE SALISBURY HIGH CTLR DSNDED ACR X TO FL280 AFTER COORDINATING WITH US AND AFTER HE REALIZED HE WAS GIVING US A PAIR OF FL310'S. WE COULD NOT SEE THE ALT ON NBOUND ACR Y BECAUSE THE DATA TAG WAS OVERLAPPED WITH A PASSING ACFT. TFC CONDITIONS WERE MODERATE-HEAVY WITH OJT ON RADAR IN PROGRESS. 2 OTHER ACFT WERE ON VECTORS FOR WX AND TFC AT THE TIME. WHEN WE MOVED THE DATA TAG ON ACR Y AND THE TAG OF ACR X WHO WAS NOW ALSO OVERLAPPING PASSING TFC, I SAW THE CONFLICTION AND GAVE IMMEDIATE TURNS TO BOTH AND CALLED TFC TO BOTH PLTS WHO RPTED SEEING EACH OTHER. ACFT PASSED APPROX 1 MI AND APPROX 500'. OTHER: SIMILAR CALL SIGNS, OJT ON RADAR IN PROGRESS, WX DEVIATIONS, CORP JET AT FL310 REAL SLOW WITH NUMEROUS OTHER ACFT AT FL310 DURING MODERATE-HEAVY TFC CONDITIONS. ANOTHER CORP AT FL260 SWBND ACROSS WASHINGTON AND BALTIMORE DEP PATH CLBING TO FL260. ACR X AT M82 OVERTAKING ACR Z AT M78 BOTH AT FL310. ACR Y NBOUND AT FL290 DATA TAG OVERLAPPED WITH ANOTHER PASSING ACFT. SUPPLEMENTAL INFO FROM ACN 93112: WE WERE CRUISING AT FL310 AND WERE ADVISED THAT WE WERE OVERTAKING SLOWER TFC. WE WERE GIVEN DSCNT CLRNC TO FL280. ATC CHANGED US TO ANOTHER FREQ AND WE WERE GIVEN AN IMMEDIATE LEFT TURN. I STOPPED THE DSCNT AT 29600' WHILE INITIATING A 30 DEG BANK LEFT TURN. THE ON-COMING TFC WAS AT FL290 ON THE SAME FREQ. HE INITIATED A LEFT TURN ALSO. WE BOTH THEN HAD EACH OTHER VISUALLY, 600' VERT, 1/2 MI HORIZ. BETTER ATC COORD WAS NEEDED IN THIS CASE.

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.