Narrative:

12 DME from austin VOR at 5000 ft MSL in IMC conditions, we received a TA. We were receiving radar vectors by austin approach control, 'turn to a heading of 120 degrees, small aircraft at 12 O'clock.' we turned to a heading of 120 degrees which would take us into some heavy precipitation. We requested a turn to a heading of 115 degrees to avoid the WX. About the time we expected a readback from approach control, we received our TCASII RA (TCASII indicated that the traffic was 100 ft below our aircraft, and less than 1 NM at 12 O'clock). We immediately took appropriate evasive measures and climbed to 6000 ft, and advised approach control. Had we not believed our TCASII, and climbed as it had directed, we might have had a midair collision.

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Original NASA ASRS Text

Title: AN ACR MLG CLBED IN RESPONSE TO A TCASII COMMAND.

Narrative: 12 DME FROM AUSTIN VOR AT 5000 FT MSL IN IMC CONDITIONS, WE RECEIVED A TA. WE WERE RECEIVING RADAR VECTORS BY AUSTIN APCH CTL, 'TURN TO A HDG OF 120 DEGS, SMA AT 12 O'CLOCK.' WE TURNED TO A HDG OF 120 DEGS WHICH WOULD TAKE US INTO SOME HVY PRECIPITATION. WE REQUESTED A TURN TO A HDG OF 115 DEGS TO AVOID THE WX. ABOUT THE TIME WE EXPECTED A READBACK FROM APCH CTL, WE RECEIVED OUR TCASII RA (TCASII INDICATED THAT THE TFC WAS 100 FT BELOW OUR ACFT, AND LESS THAN 1 NM AT 12 O'CLOCK). WE IMMEDIATELY TOOK APPROPRIATE EVASIVE MEASURES AND CLBED TO 6000 FT, AND ADVISED APCH CTL. HAD WE NOT BELIEVED OUR TCASII, AND CLBED AS IT HAD DIRECTED, WE MIGHT HAVE HAD A MIDAIR COLLISION.

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.