Narrative:

Air carrier X was issued traffic 1 O'clock 8 mi same direction at 170, air carrier Y was told to maintain 160. Air carrier X reported IMC. Air carrier Y told to maintain a 090 degree heading for climbing traffic. Air carrier Y acknowledged. Air carrier Z, 15 mit air carrier X, issued clearance to climb to FL230 and maintain a 030 degree heading for climb. Air carrier X reported traffic in sight and maintaining 160. I told air carrier X the clearance was for company to maintain 160. Then I said again air carrier Z climb and maintain FL230 fly heading of 030 for climb. Air carrier X said again I have traffic in sight leaving 160 for FL230. I observed air carrier X leaving 163 with air carrier Y only 3.5 to 4 mi south of air carrier Y. I told air carrier X to maintain 160. Air carrier X said I'm leaving 175. I told him in that case climb and maintain FL230. I think I should have gotten acknowledgement from air carrier X for maintaining 160 to clarify situation. I was confused because I thought I had transposed call signs but couldn't be sure. Air carrier X should have listened better to a clearance given at least twice. Air carrier Z needed to listen up too because he never acknowledged clearance or even questioned if he had gotten one.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD RADAR SEPARATION FROM ACR Y. ACR X RESPONDED TO CLRNC FOR ACR Z SAME COMPANY. SYS ERROR.

Narrative: ACR X WAS ISSUED TFC 1 O'CLOCK 8 MI SAME DIRECTION AT 170, ACR Y WAS TOLD TO MAINTAIN 160. ACR X RPTED IMC. ACR Y TOLD TO MAINTAIN A 090 DEG HDG FOR CLBING TFC. ACR Y ACKNOWLEDGED. ACR Z, 15 MIT ACR X, ISSUED CLRNC TO CLB TO FL230 AND MAINTAIN A 030 DEG HDG FOR CLB. ACR X RPTED TFC IN SIGHT AND MAINTAINING 160. I TOLD ACR X THE CLRNC WAS FOR COMPANY TO MAINTAIN 160. THEN I SAID AGAIN ACR Z CLB AND MAINTAIN FL230 FLY HDG OF 030 FOR CLB. ACR X SAID AGAIN I HAVE TFC IN SIGHT LEAVING 160 FOR FL230. I OBSERVED ACR X LEAVING 163 WITH ACR Y ONLY 3.5 TO 4 MI S OF ACR Y. I TOLD ACR X TO MAINTAIN 160. ACR X SAID I'M LEAVING 175. I TOLD HIM IN THAT CASE CLB AND MAINTAIN FL230. I THINK I SHOULD HAVE GOTTEN ACKNOWLEDGEMENT FROM ACR X FOR MAINTAINING 160 TO CLARIFY SITUATION. I WAS CONFUSED BECAUSE I THOUGHT I HAD TRANSPOSED CALL SIGNS BUT COULDN'T BE SURE. ACR X SHOULD HAVE LISTENED BETTER TO A CLRNC GIVEN AT LEAST TWICE. ACR Z NEEDED TO LISTEN UP TOO BECAUSE HE NEVER ACKNOWLEDGED CLRNC OR EVEN QUESTIONED IF HE HAD GOTTEN ONE.

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.