DEPARTING FD328 OFF PHL RWY 17 OVERTAKES PREVIOUS DEPARTING A320 DEPARTING CAUSING TCASII RA AND CONFLICT.

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ACR X OFF RWY 9L WAS CLBED TO 10000 FT AND TOLD TO TURN L TO PTW LEAVING 3000 FT. ACR Y OFF RWY 8 ON A 040 DEG HDG WAS CLBED TO 9000 FT. ACR X GOT TO 3000 FT; TURNED TO PTW AND SEEMED TO HAVE STOPPED CLBING. THE D328 MAINTAINING A NORMAL CLB RATE; CLBED THROUGH THE A320'S ALT. AFTER LEVELING AT 3000 FT ON A HDG AWAY FROM THE D328; THE A320 WAS ASSIGNED 10000 FT AGAIN; THE ACFT THEN DSNDED TO 2400 FT BEFORE STARTING ITS CLB. SUPPLEMENTAL INFO FROM ACN 536624: AFTER ROLLING OUT OF TURN AT 3300 FT; TCASII TA FOLLOWED BY 'DSND;' I DSNDED TO BELOW 3000 FT AND ACQUIRED TFC (DONIER COMMUTER) AT 10 O'CLOCK POS HIGH (500 FT ABOVE). I MAINTAINED A VISUAL ON HIM AND SUBSEQUENTLY PASSED DIRECTLY UNDERNEATH HIM 500 FT. SINCE AUTOTHROTTLES WERE IN 'CLB' MODE; AIRSPD ACCELERATED TO OVER 280 KIAS AT AN ALT OF 2500 FT. PRIOR TO PASSING UNDERNEATH; TCASII RA GAVE ME A 'CLB.' I IGNORED THIS INSTRUCTION UNTIL I WAS SURE I WAS WELL PAST THE TFC AND GOT VERIFICATION AND RECLRED TO 10000 FT BY ATC. WE WERE AT ALMOST MAX GROSS WT (198800 LBS) AND CLBING AT A SLOW RATE. WHEN I ASKED IF HE HAD SEEN THE POTENTIAL CONFLICT. HE HESITATED; THEN REPLIED 'I THOUGHT YOU WOULD BE A LOT HIGHER.' THE CTLRS ARE SO USED TO TFC REACTING A STANDARD WAY; BUT HAVE TO REALIZE THE ACFT WON'T ALWAYS DO WHAT THEY ARE USED TO. SUPPLEMENTAL INFO FROM ACN 536631: REPORT NOT SUPPLIED.