Narrative:

On descent, on the macey arrival into atl, on ZTL, we were descending through 13800 ft, a few mi outside macey, when TCASII alerted us to a TA, then an RA, on pop-up VFR traffic at 13500 ft. The advisory was to climb at approximately 1200 FPM. I immediately disconnected the autoplt and autothrottles, and climbed at the prescribed rate. At 13900 ft, TCASII advised to monitor vertical speed then clear of traffic. We topped out at 14000 ft. ZTL issued a traffic warning well after we had initiated an evasive maneuver. It was a hazy day and we never saw the conflicting traffic, so we only knew we missed it by 200 ft vertically from the TCASII readout.

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Original NASA ASRS Text

Title: ACR MLG ON DSCNT ON MACEY STAR ATL GETS TCASII TA AND RA AT 13800 FT ON VFR TFC AT 13500 FT. FOLLOWED ALERT AND AT 14000 FT GOT MONITOR VERT SPD. CTLR ADVISED OF TFC AFTER THE EVASIVE MANEUVER.

Narrative: ON DSCNT, ON THE MACEY ARR INTO ATL, ON ZTL, WE WERE DSNDING THROUGH 13800 FT, A FEW MI OUTSIDE MACEY, WHEN TCASII ALERTED US TO A TA, THEN AN RA, ON POP-UP VFR TFC AT 13500 FT. THE ADVISORY WAS TO CLB AT APPROX 1200 FPM. I IMMEDIATELY DISCONNECTED THE AUTOPLT AND AUTOTHROTTLES, AND CLBED AT THE PRESCRIBED RATE. AT 13900 FT, TCASII ADVISED TO MONITOR VERT SPD THEN CLR OF TFC. WE TOPPED OUT AT 14000 FT. ZTL ISSUED A TFC WARNING WELL AFTER WE HAD INITIATED AN EVASIVE MANEUVER. IT WAS A HAZY DAY AND WE NEVER SAW THE CONFLICTING TFC, SO WE ONLY KNEW WE MISSED IT BY 200 FT VERTLY FROM THE TCASII READOUT.

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.