Narrative:

We were with approach control on a vector of 030 degrees, 11000 ft, airspeed 210 KTS assigned. Received a TA. Checking the radar screen we noticed traffic below us. This traffic was no factor as it remained below us with no decrease in_the required 1000 ft separation. A moment later another TA at our 1 O'clock position. We quickly obtained a visual sighting of the aircraft in question, an md-88 on climb out from atl. We expected the aircraft to level at 10000 ft as is standard for departure in atl. We then heard an RA of the same traffic instructing us to descend, followed by an increase descent RA. Keeping in mind the last TA of traffic somewhere below us, and having the new traffic visual we decided that a descent was not the best maneuver. When it became clear to us that the conflicting aircraft was not leveling at 10000 ft and was going to climb up to or past our altitude, I disengaged the autoplt, initiated a 20-30 degree left bank, keeping the traffic in sight. After 20-30 degrees of turn we were well clear of the conflict. After the conflicting aircraft passed off our right wing, I returned to our assigned heading, reengaged the autoplt, then the captain informed ATC of our temporary heading change to avoid an aircraft passing our altitude. Since we had a visual on the traffic I believe a descent was not a good maneuver. First, we may have hurt some passenger or our flight attendants by pushing over the aircraft. Second, we may have caused a 'domino' effect by descending into the area of multiple other aircraft around the field. A nice smooth 20-30 degree heading change worked very well. We were very aware if we were IFR or had no visual we would have aggressively followed the RA commands. In this case the heading change was the best maneuver.

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Original NASA ASRS Text

Title: MLG HAS TCASII RA WITH MLG ON CLB.

Narrative: WE WERE WITH APCH CTL ON A VECTOR OF 030 DEGS, 11000 FT, AIRSPD 210 KTS ASSIGNED. RECEIVED A TA. CHKING THE RADAR SCREEN WE NOTICED TFC BELOW US. THIS TFC WAS NO FACTOR AS IT REMAINED BELOW US WITH NO DECREASE IN_THE REQUIRED 1000 FT SEPARATION. A MOMENT LATER ANOTHER TA AT OUR 1 O'CLOCK POS. WE QUICKLY OBTAINED A VISUAL SIGHTING OF THE ACFT IN QUESTION, AN MD-88 ON CLBOUT FROM ATL. WE EXPECTED THE ACFT TO LEVEL AT 10000 FT AS IS STANDARD FOR DEP IN ATL. WE THEN HEARD AN RA OF THE SAME TFC INSTRUCTING US TO DSND, FOLLOWED BY AN INCREASE DSCNT RA. KEEPING IN MIND THE LAST TA OF TFC SOMEWHERE BELOW US, AND HAVING THE NEW TFC VISUAL WE DECIDED THAT A DSCNT WAS NOT THE BEST MANEUVER. WHEN IT BECAME CLR TO US THAT THE CONFLICTING ACFT WAS NOT LEVELING AT 10000 FT AND WAS GOING TO CLB UP TO OR PAST OUR ALT, I DISENGAGED THE AUTOPLT, INITIATED A 20-30 DEG L BANK, KEEPING THE TFC IN SIGHT. AFTER 20-30 DEGS OF TURN WE WERE WELL CLR OF THE CONFLICT. AFTER THE CONFLICTING ACFT PASSED OFF OUR R WING, I RETURNED TO OUR ASSIGNED HDG, REENGAGED THE AUTOPLT, THEN THE CAPT INFORMED ATC OF OUR TEMPORARY HDG CHANGE TO AVOID AN ACFT PASSING OUR ALT. SINCE WE HAD A VISUAL ON THE TFC I BELIEVE A DSCNT WAS NOT A GOOD MANEUVER. FIRST, WE MAY HAVE HURT SOME PAX OR OUR FLT ATTENDANTS BY PUSHING OVER THE ACFT. SECOND, WE MAY HAVE CAUSED A 'DOMINO' EFFECT BY DSNDING INTO THE AREA OF MULTIPLE OTHER ACFT AROUND THE FIELD. A NICE SMOOTH 20-30 DEG HDG CHANGE WORKED VERY WELL. WE WERE VERY AWARE IF WE WERE IFR OR HAD NO VISUAL WE WOULD HAVE AGGRESSIVELY FOLLOWED THE RA COMMANDS. IN THIS CASE THE HDG CHANGE WAS THE BEST MANEUVER.

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.