Narrative:

Air carrier X observed converging VFR traffic at 13500 ft MSL while descending through 14000 ft MSL. Pilot climbed back up to 14000 ft MSL to avoid collision. VFR traffic was not observed by ATC.

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Original NASA ASRS Text

Title: S46 CTLR DESCRIBED TCAS RA EVENT WHEN DESCENDING ACR ARR RESPONDED TO ALERT.

Narrative: ACR X OBSERVED CONVERGING VFR TFC AT 13500 FT MSL WHILE DSNDING THROUGH 14000 FT MSL. PLT CLBED BACK UP TO 14000 FT MSL TO AVOID COLLISION. VFR TFC WAS NOT OBSERVED BY ATC.

Data retrieved from NASA's ASRS site as of May 2009 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.