Narrative:

After takeoff from phl we contacted phl departure control and were vectored southwest. As we climbed above dash 8 traffic that had departed ahead, ATC then cleared us to turn left direct to ditch intersection, and we complied. After rolling out of the turn and level at 10000 ft, we got a TCASII 'traffic' call and referred to the navigation display. Intruder traffic displayed at 10 O'clock position 4 NM at an altitude 500 ft below us with a trend arrow indicating a climb. TCASII then broadcast a 'climb' RA. I disconnected the autoplt and started a climb. TCASII almost immediately called 'monitor vertical rate' and soon issued 'clear of conflict.' we returned to our clearance altitude with a maximum altitude deviation of +300 ft. Due to frequency congestion and subsequent frequency change given to us, discussion of the event was limited to advising ATC after the fact. The intruder aircraft was the same aircraft we had been vectored around and climbed above. It is not known to me if he missed his altitude or was cleared through our altitude. Point of closest passage was about 800 ft at 2 NM.

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Original NASA ASRS Text

Title: F100 CREW OFF PHL CLBED ABOVE A DH8 AND LEVELED AT 10000 FT. ATC THEN CLRED THE F100 DIRECT TO AN INTXN AND THE CREW RECEIVED A TCASII RA INDICATING CLB. THE INTRUDER ACFT WAS THE DH8 THEY HAD PREVIOUSLY OVERTAKEN.

Narrative: AFTER TKOF FROM PHL WE CONTACTED PHL DEP CTL AND WERE VECTORED SW. AS WE CLBED ABOVE DASH 8 TFC THAT HAD DEPARTED AHEAD, ATC THEN CLRED US TO TURN L DIRECT TO DITCH INTXN, AND WE COMPLIED. AFTER ROLLING OUT OF THE TURN AND LEVEL AT 10000 FT, WE GOT A TCASII 'TFC' CALL AND REFERRED TO THE NAV DISPLAY. INTRUDER TFC DISPLAYED AT 10 O'CLOCK POS 4 NM AT AN ALT 500 FT BELOW US WITH A TREND ARROW INDICATING A CLB. TCASII THEN BROADCAST A 'CLB' RA. I DISCONNECTED THE AUTOPLT AND STARTED A CLB. TCASII ALMOST IMMEDIATELY CALLED 'MONITOR VERT RATE' AND SOON ISSUED 'CLR OF CONFLICT.' WE RETURNED TO OUR CLRNC ALT WITH A MAX ALTDEV OF +300 FT. DUE TO FREQ CONGESTION AND SUBSEQUENT FREQ CHANGE GIVEN TO US, DISCUSSION OF THE EVENT WAS LIMITED TO ADVISING ATC AFTER THE FACT. THE INTRUDER ACFT WAS THE SAME ACFT WE HAD BEEN VECTORED AROUND AND CLBED ABOVE. IT IS NOT KNOWN TO ME IF HE MISSED HIS ALT OR WAS CLRED THROUGH OUR ALT. POINT OF CLOSEST PASSAGE WAS ABOUT 800 FT AT 2 NM.

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.