Narrative:

ATC called traffic. Air carrier X immediately acquired traffic at 10 O'clock 500-700 ft horizontal same altitude on a converging course. Intruder was in a 10-15 degree right bank. A collision appeared imminent. I banked 60 degrees to the right through 90 degree azimuth and performed 2-3 G pull up through 300 ft altitude. Intruder apparently also performed a right turn, climbing maneuver. First officer acquired intruder at 5 O'clock same altitude and again turning toward us. So we descended with traffic at 6 O'clock and did not see him again. Intruder Y was apparently being worked by another controller. ATC had advised us to turn left (toward traffic) and descend. Possibly the intruder Y was also given conflicting RA. The controller did not issue a TA or otherwise convey a sense of urgency. TCASII would have helped us to avoid this conflict.

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Original NASA ASRS Text

Title: ACR X NON ADHERENCE TO ATC INSTRUCTIONS TURNED WRONG WAY HAD NMAC WITH Y. SEE AND AVOID. EVASIVE ACTION TAKEN.

Narrative: ATC CALLED TFC. ACR X IMMEDIATELY ACQUIRED TFC AT 10 O'CLOCK 500-700 FT HORIZ SAME ALT ON A CONVERGING COURSE. INTRUDER WAS IN A 10-15 DEG R BANK. A COLLISION APPEARED IMMINENT. I BANKED 60 DEGS TO THE R THROUGH 90 DEG AZIMUTH AND PERFORMED 2-3 G PULL UP THROUGH 300 FT ALT. INTRUDER APPARENTLY ALSO PERFORMED A R TURN, CLBING MANEUVER. FO ACQUIRED INTRUDER AT 5 O'CLOCK SAME ALT AND AGAIN TURNING TOWARD US. SO WE DSNDED WITH TFC AT 6 O'CLOCK AND DID NOT SEE HIM AGAIN. INTRUDER Y WAS APPARENTLY BEING WORKED BY ANOTHER CTLR. ATC HAD ADVISED US TO TURN L (TOWARD TFC) AND DSND. POSSIBLY THE INTRUDER Y WAS ALSO GIVEN CONFLICTING RA. THE CTLR DID NOT ISSUE A TA OR OTHERWISE CONVEY A SENSE OF URGENCY. TCASII WOULD HAVE HELPED US TO AVOID THIS CONFLICT.

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.