Narrative:

TCASII traffic showed south to north in movement as we turned base to final to runway 9L mia. It started at 600 ft below and at 100 ft TCASII RA (monitor vertical descent) initial command down followed by immediate climb. Traffic showed 100 ft, right on the nose. Deviated right and climbed. We had a conversation with tower afterward. He stated no radar traffic in that area. Resumed to normal landing.

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Original NASA ASRS Text

Title: ALT HDG DEV UPON RECEIPT OF TCASII RA OF XING TFC.

Narrative: TCASII TFC SHOWED S TO N IN MOVEMENT AS WE TURNED BASE TO FINAL TO RWY 9L MIA. IT STARTED AT 600 FT BELOW AND AT 100 FT TCASII RA (MONITOR VERT DSCNT) INITIAL COMMAND DOWN FOLLOWED BY IMMEDIATE CLB. TFC SHOWED 100 FT, RIGHT ON THE NOSE. DEVIATED R AND CLBED. WE HAD A CONVERSATION WITH TWR AFTERWARD. HE STATED NO RADAR TFC IN THAT AREA. RESUMED TO NORMAL LNDG.

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.