Narrative:

During descent from 12000 ft MSL to 8000 ft MSL, approaching 9000 ft MSL on the buntr 1 arrival, we had just turned to a 225 degree heading EPR the arrival procedure when approach control called out traffic at 12 O'clock below us. Observing traffic on TCASII (wht, sign.) that appeared to be a potential conflict, we requested radar avoidance vector, and slowed our descent. ATC directed a turn to the right, and we complied. At that point, the traffic in question became an amber TCASII advisory, followed shortly by a red RA 'resource descent' and then 'monitor vertical speed.' in conjunction with the initial RA, we sighted the aircraft approximately 500 ft below us and slightly to our left at roughly 8500 ft MSL, and continued a shallow right turn to increase separation. Essentially, the RA reconfirmed what we had initiated. Following 'clear of conflict,' we advised ATC that we had the traffic insight, received radar vectors, resumed our descent, advised ATC of our RA, and landed uneventfully. In short, the system (ATC, pilots, TCASII, etc) worked. Hopefully, general aviation is aware of the numerous IFR arrival (and departure) corridors in and out of sky harbor.

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Original NASA ASRS Text

Title: A320 FLT CREW TAKE EVASIVE ACTION TO AVOID A SEL ACFT ON THE EDGE OF THE PHX CLASS B AIRSPACE.

Narrative: DURING DSCNT FROM 12000 FT MSL TO 8000 FT MSL, APCHING 9000 FT MSL ON THE BUNTR 1 ARR, WE HAD JUST TURNED TO A 225 DEG HDG EPR THE ARR PROC WHEN APCH CTL CALLED OUT TFC AT 12 O'CLOCK BELOW US. OBSERVING TFC ON TCASII (WHT, SIGN.) THAT APPEARED TO BE A POTENTIAL CONFLICT, WE REQUESTED RADAR AVOIDANCE VECTOR, AND SLOWED OUR DSCNT. ATC DIRECTED A TURN TO THE R, AND WE COMPLIED. AT THAT POINT, THE TFC IN QUESTION BECAME AN AMBER TCASII ADVISORY, FOLLOWED SHORTLY BY A RED RA 'RESOURCE DSCNT' AND THEN 'MONITOR VERT SPD.' IN CONJUNCTION WITH THE INITIAL RA, WE SIGHTED THE ACFT APPROX 500 FT BELOW US AND SLIGHTLY TO OUR L AT ROUGHLY 8500 FT MSL, AND CONTINUED A SHALLOW R TURN TO INCREASE SEPARATION. ESSENTIALLY, THE RA RECONFIRMED WHAT WE HAD INITIATED. FOLLOWING 'CLR OF CONFLICT,' WE ADVISED ATC THAT WE HAD THE TFC INSIGHT, RECEIVED RADAR VECTORS, RESUMED OUR DSCNT, ADVISED ATC OF OUR RA, AND LANDED UNEVENTFULLY. IN SHORT, THE SYS (ATC, PLTS, TCASII, ETC) WORKED. HOPEFULLY, GENERAL AVIATION IS AWARE OF THE NUMEROUS IFR ARR (AND DEP) CORRIDORS IN AND OUT OF SKY HARBOR.

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.