Narrative:

Flying the blewe 1 arrival, ATC gave us a descent to cross the sewzy intersection at 13000 ft. Descending through FL180 at 2000 FPM, we received a TA indicating there was an aircraft 500 ft below us. I disconnected the autoplt and began to level the aircraft when at approximately 17800 ft we received an RA to climb. I began climbing the aircraft to comply with the RA while my first officer called ATC advising them of our actions and asking them about the traffic. My navigation display was positioned on the 60 NM range and the aircraft appeared directly below us. At no time had we received an advisory of this aircraft from ATC. After our call, the controller told us the aircraft was VFR level at 17500 ft and was not a problem. He then asked which way we were deviating. We told him we were climbing. He then asked us to resume our descent to cross sewzy at 13000 ft. I then got on the radio and responded that I thought the aircraft was in fact a problem when I was descending through his altitude at 2000 FPM. At 13 DME from sewzy the RA quit and we resumed our descent. Controller said he was busy so there was no further discussion and we were given a frequency change.

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Original NASA ASRS Text

Title: FK10 CREW HAD A TCASII RA.

Narrative: FLYING THE BLEWE 1 ARR, ATC GAVE US A DSCNT TO CROSS THE SEWZY INTXN AT 13000 FT. DSNDING THROUGH FL180 AT 2000 FPM, WE RECEIVED A TA INDICATING THERE WAS AN ACFT 500 FT BELOW US. I DISCONNECTED THE AUTOPLT AND BEGAN TO LEVEL THE ACFT WHEN AT APPROX 17800 FT WE RECEIVED AN RA TO CLB. I BEGAN CLBING THE ACFT TO COMPLY WITH THE RA WHILE MY FO CALLED ATC ADVISING THEM OF OUR ACTIONS AND ASKING THEM ABOUT THE TFC. MY NAV DISPLAY WAS POSITIONED ON THE 60 NM RANGE AND THE ACFT APPEARED DIRECTLY BELOW US. AT NO TIME HAD WE RECEIVED AN ADVISORY OF THIS ACFT FROM ATC. AFTER OUR CALL, THE CTLR TOLD US THE ACFT WAS VFR LEVEL AT 17500 FT AND WAS NOT A PROB. HE THEN ASKED WHICH WAY WE WERE DEVIATING. WE TOLD HIM WE WERE CLBING. HE THEN ASKED US TO RESUME OUR DSCNT TO CROSS SEWZY AT 13000 FT. I THEN GOT ON THE RADIO AND RESPONDED THAT I THOUGHT THE ACFT WAS IN FACT A PROB WHEN I WAS DSNDING THROUGH HIS ALT AT 2000 FPM. AT 13 DME FROM SEWZY THE RA QUIT AND WE RESUMED OUR DSCNT. CTLR SAID HE WAS BUSY SO THERE WAS NO FURTHER DISCUSSION AND WE WERE GIVEN A FREQ CHANGE.

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.