Narrative:

Departed runway 16R. Assigned runway heading to 3000 ft. Shortly after takeoff, prior to ATC TA, saw target on TCASII inside 6 mi range, 2 O'clock position and at least 1000 ft above. ATC then advised C172 VFR traffic at same position. Traffic was not in sight. ATC then issued right turn 270 degrees, climb to 10000 ft. I initiated climb and turn but still not seeing traffic, that I was turning toward and climbing into, stopped turn on 180 degree heading. Reduced climb approaching 3000 ft. Advised first officer to inform ATC as such. ATC advised maintain 3000 ft. At this time, acquired traffic visually 1-2 O'clock position and above our altitude. Traffic passed close off our left and above us. ATC advised to maintain visual separation and climb to 10000 ft. Simultaneously, with visual acquisition, received TCASII. Both first officer and I confirmed traffic was above us, and climb would have worsened situation. No further action nor instruction from ATC relative to traffic given. Proceeded normally. Supplemental information from acn 549380: a C172 was at our 1-2 O'clock position at 3500 ft. Our instructions were given to us as we were passing through 3000 ft. We descended back down to 3000 ft and asked for a 180 degree heading. Departure stated negative and to continue turn and climb. We passed under the C172 by approximately 500 ft.

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Original NASA ASRS Text

Title: NMAC OCCURS WHEN DEP CTLR FAILS TO PROVIDE SEPARATION BTWN A DEP EMJ AND A XING C172 S OF JAN, MS.

Narrative: DEPARTED RWY 16R. ASSIGNED RWY HDG TO 3000 FT. SHORTLY AFTER TKOF, PRIOR TO ATC TA, SAW TARGET ON TCASII INSIDE 6 MI RANGE, 2 O'CLOCK POS AND AT LEAST 1000 FT ABOVE. ATC THEN ADVISED C172 VFR TFC AT SAME POS. TFC WAS NOT IN SIGHT. ATC THEN ISSUED R TURN 270 DEGS, CLB TO 10000 FT. I INITIATED CLB AND TURN BUT STILL NOT SEEING TFC, THAT I WAS TURNING TOWARD AND CLBING INTO, STOPPED TURN ON 180 DEG HDG. REDUCED CLB APCHING 3000 FT. ADVISED FO TO INFORM ATC AS SUCH. ATC ADVISED MAINTAIN 3000 FT. AT THIS TIME, ACQUIRED TFC VISUALLY 1-2 O'CLOCK POS AND ABOVE OUR ALT. TFC PASSED CLOSE OFF OUR L AND ABOVE US. ATC ADVISED TO MAINTAIN VISUAL SEPARATION AND CLB TO 10000 FT. SIMULTANEOUSLY, WITH VISUAL ACQUISITION, RECEIVED TCASII. BOTH FO AND I CONFIRMED TFC WAS ABOVE US, AND CLB WOULD HAVE WORSENED SIT. NO FURTHER ACTION NOR INSTRUCTION FROM ATC RELATIVE TO TFC GIVEN. PROCEEDED NORMALLY. SUPPLEMENTAL INFO FROM ACN 549380: A C172 WAS AT OUR 1-2 O'CLOCK POS AT 3500 FT. OUR INSTRUCTIONS WERE GIVEN TO US AS WE WERE PASSING THROUGH 3000 FT. WE DSNDED BACK DOWN TO 3000 FT AND ASKED FOR A 180 DEG HDG. DEP STATED NEGATIVE AND TO CONTINUE TURN AND CLB. WE PASSED UNDER THE C172 BY APPROX 500 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.