Narrative:

At approximately 5000 ft MSL on radar vectors for approach to runway 27R at phl, I observed traffic displayed on TCASII at about our 2 O'clock position and indicating level at 600 ft below us. We received no information about the traffic from approach control. I asked the other 2 crew members to assist me in locating the traffic, but were unable to find him visually. The traffic was about 4 mi out at the time but appeared to be converging on us. Approach control issued us a turn after unsuccessful attempts to inquire about traffic by my first officer (turn was not issued to avoid traffic as far as we know). (Approach control was very busy and I had requested that my first officer inquire about the traffic.) before we could begin a turn we received a TCASII RA for climb, crossing climb. I observed an up trend arrow indicating that our traffic was also climbing. I followed the TCASII guidance and climbed to approximately 5500 ft MSL, at which time we saw our traffic and received a clear of conflict response from TCASII. We then descended back to our assigned altitude of 5000 ft MSL after advising ATC of the RA. ATC apologized to us, and we felt that TCASII did the job it was designed to do. P.south. (We believe that ATC was very busy especially due to turbulence and some convective activity in the area.)

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Original NASA ASRS Text

Title: AN ACR B727 HAS TO EXECUTE AN ALT EXCURSION TO AVOID SMA TFC THAT WAS NOT BEING CONSIDERED BY PHL APCH CTLR. A POTENTIAL CONFLICT.

Narrative: AT APPROX 5000 FT MSL ON RADAR VECTORS FOR APCH TO RWY 27R AT PHL, I OBSERVED TFC DISPLAYED ON TCASII AT ABOUT OUR 2 O'CLOCK POS AND INDICATING LEVEL AT 600 FT BELOW US. WE RECEIVED NO INFO ABOUT THE TFC FROM APCH CTL. I ASKED THE OTHER 2 CREW MEMBERS TO ASSIST ME IN LOCATING THE TFC, BUT WERE UNABLE TO FIND HIM VISUALLY. THE TFC WAS ABOUT 4 MI OUT AT THE TIME BUT APPEARED TO BE CONVERGING ON US. APCH CTL ISSUED US A TURN AFTER UNSUCCESSFUL ATTEMPTS TO INQUIRE ABOUT TFC BY MY FO (TURN WAS NOT ISSUED TO AVOID TFC AS FAR AS WE KNOW). (APCH CTL WAS VERY BUSY AND I HAD REQUESTED THAT MY FO INQUIRE ABOUT THE TFC.) BEFORE WE COULD BEGIN A TURN WE RECEIVED A TCASII RA FOR CLB, XING CLB. I OBSERVED AN UP TREND ARROW INDICATING THAT OUR TFC WAS ALSO CLBING. I FOLLOWED THE TCASII GUIDANCE AND CLBED TO APPROX 5500 FT MSL, AT WHICH TIME WE SAW OUR TFC AND RECEIVED A CLR OF CONFLICT RESPONSE FROM TCASII. WE THEN DSNDED BACK TO OUR ASSIGNED ALT OF 5000 FT MSL AFTER ADVISING ATC OF THE RA. ATC APOLOGIZED TO US, AND WE FELT THAT TCASII DID THE JOB IT WAS DESIGNED TO DO. P.S. (WE BELIEVE THAT ATC WAS VERY BUSY ESPECIALLY DUE TO TURB AND SOME CONVECTIVE ACTIVITY IN THE AREA.)

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.