Narrative:

Upon clearance for takeoff on runway 4R, mdw tower instructed us to turn left heading 250 degrees and informed us that there was 'cessna' traffic maneuvering west of the field and they would keep us advised. As PF, I commenced a left turn at 500 ft AGL. Once established in the turn, a target appeared in yellow on the TCASII ivsi display. It was depicted at 10-11 O'clock position, 300 ft above our altitude. We were unable to make visual contact and the aural TA sounded. A continued left turn would have put us dangerously close to the target. I rolled wings level as not to continue turning toward the target now displayed less than 1 mi, 100 ft above our altitude at 11 O'clock. Visual contact was not made and the target appeared to be closing north on us. I commenced a right turn until the target was safely behind us then reinitiated the left turn to the assigned heading. The first officer had already notified mdw tower of our maneuver when they informed us that the cessna traffic had us in sight and would maintain separation.

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Original NASA ASRS Text

Title: CAPT OF A B727 TOOK EVASIVE ACTION DURING INITIAL CLB, IN RESPONSE TO TCASII RA AND VISUAL SIGHTING OF A CESSNA MANEUVERING NEAR THE ARPT. TA WAS GIVEN.

Narrative: UPON CLRNC FOR TKOF ON RWY 4R, MDW TWR INSTRUCTED US TO TURN L HDG 250 DEGS AND INFORMED US THAT THERE WAS 'CESSNA' TFC MANEUVERING W OF THE FIELD AND THEY WOULD KEEP US ADVISED. AS PF, I COMMENCED A L TURN AT 500 FT AGL. ONCE ESTABLISHED IN THE TURN, A TARGET APPEARED IN YELLOW ON THE TCASII IVSI DISPLAY. IT WAS DEPICTED AT 10-11 O'CLOCK POS, 300 FT ABOVE OUR ALT. WE WERE UNABLE TO MAKE VISUAL CONTACT AND THE AURAL TA SOUNDED. A CONTINUED L TURN WOULD HAVE PUT US DANGEROUSLY CLOSE TO THE TARGET. I ROLLED WINGS LEVEL AS NOT TO CONTINUE TURNING TOWARD THE TARGET NOW DISPLAYED LESS THAN 1 MI, 100 FT ABOVE OUR ALT AT 11 O'CLOCK. VISUAL CONTACT WAS NOT MADE AND THE TARGET APPEARED TO BE CLOSING N ON US. I COMMENCED A R TURN UNTIL THE TARGET WAS SAFELY BEHIND US THEN REINITIATED THE L TURN TO THE ASSIGNED HDG. THE FO HAD ALREADY NOTIFIED MDW TWR OF OUR MANEUVER WHEN THEY INFORMED US THAT THE CESSNA TFC HAD US IN SIGHT AND WOULD MAINTAIN SEPARATION.

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.