Narrative:

While on boids arrival into dfw TCASII issued a 'descend now' for an RA traffic at about 10 O'clock and 3-4 mi. As per TCASII descended to 10500 ft and TCASII changed to 'monitor vertical speed' and at about the same time a 'clear of conflict.' traffic was never visually idented and ATC said that the traffic was behind us.

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Original NASA ASRS Text

Title: ACR MLG ALTDEV EXCURSION FROM CLRNC ALT IN RESPONSE TO TCASII RA.

Narrative: WHILE ON BOIDS ARR INTO DFW TCASII ISSUED A 'DSND NOW' FOR AN RA TFC AT ABOUT 10 O'CLOCK AND 3-4 MI. AS PER TCASII DSNDED TO 10500 FT AND TCASII CHANGED TO 'MONITOR VERT SPD' AND AT ABOUT THE SAME TIME A 'CLR OF CONFLICT.' TFC WAS NEVER VISUALLY IDENTED AND ATC SAID THAT THE TFC WAS BEHIND US.

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.