Narrative:

We departed myf. Radar vectors were assigned and then we were cleared direct ocn. We were level 6000 ft and direct ocn approximately heading 320 degrees. We were monitoring socal 127.3 when the following happened. South of ocn, duchess traffic was called, climbing to 6500 ft. Recall duchess first on our right side and low. Then we lost visual with the duchess. It then appeared well off our left side approximately 8-9 O'clock. ATC then called a radar vector for the duchess to turn to heading 360 degrees for separation. As PIC, I then declared to the controller that the duchess radar vector would cross our path. Shortly thereafter the duchess appeared at a similar altitude to us (6000 ft) and closing quickly and headed straight for us. I then took evasive action by making an abrupt climbing turn to the right. My wife sitting in the right front seat saw the belly of the duchess as it appeared to turn sharply to also take evasive action. It seemed as if there was less than 20 ft of horizontal separation and zero vertical separation when evasive action was taken. This seemed to be an obvious error, caused by ATC giving the duchess a bad radar vector.

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Original NASA ASRS Text

Title: C182 INVOLVED IN NMAC WITH BE76 APPARENTLY DUE TO POOR ATC VECTOR TECHNIQUE, SCT, CA.

Narrative: WE DEPARTED MYF. RADAR VECTORS WERE ASSIGNED AND THEN WE WERE CLRED DIRECT OCN. WE WERE LEVEL 6000 FT AND DIRECT OCN APPROX HDG 320 DEGS. WE WERE MONITORING SOCAL 127.3 WHEN THE FOLLOWING HAPPENED. S OF OCN, DUCHESS TFC WAS CALLED, CLBING TO 6500 FT. RECALL DUCHESS FIRST ON OUR R SIDE AND LOW. THEN WE LOST VISUAL WITH THE DUCHESS. IT THEN APPEARED WELL OFF OUR L SIDE APPROX 8-9 O'CLOCK. ATC THEN CALLED A RADAR VECTOR FOR THE DUCHESS TO TURN TO HDG 360 DEGS FOR SEPARATION. AS PIC, I THEN DECLARED TO THE CTLR THAT THE DUCHESS RADAR VECTOR WOULD CROSS OUR PATH. SHORTLY THEREAFTER THE DUCHESS APPEARED AT A SIMILAR ALT TO US (6000 FT) AND CLOSING QUICKLY AND HEADED STRAIGHT FOR US. I THEN TOOK EVASIVE ACTION BY MAKING AN ABRUPT CLBING TURN TO THE R. MY WIFE SITTING IN THE R FRONT SEAT SAW THE BELLY OF THE DUCHESS AS IT APPEARED TO TURN SHARPLY TO ALSO TAKE EVASIVE ACTION. IT SEEMED AS IF THERE WAS LESS THAN 20 FT OF HORIZ SEPARATION AND ZERO VERT SEPARATION WHEN EVASIVE ACTION WAS TAKEN. THIS SEEMED TO BE AN OBVIOUS ERROR, CAUSED BY ATC GIVING THE DUCHESS A BAD RADAR VECTOR.

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.