Narrative:

WX was clear. We were taking off on runway 9L, climbing to 5000 ft. At 2000 ft, we were cleared to 10000 ft. We were on runway heading. At about 5000 ft we turned to a heading of 360 degrees. My climb rate was about 2000-3000 FPM. At 7000 ft we got a TCASII warning. It was right in the center of the screen. Within seconds, the TCASII told us to descend. Before this point, I had already started to power back and nose the plane over. ATC had said nothing up to this point. Between the 2 TCASII warnings, we asked if they had the traffic. Things were happening very quickly at this point, and I believe ATC said they did not have the traffic. The traffic was at 8000 ft. By the time we got the warning, spoke to ATC, then finally saw the traffic, I had climbed to 8500 ft. At this point ATC says to level at 8000 ft. I started slowly back toward 8000 ft. Now that we had the traffic in sight we asked ATC to continue climb to 10000 ft. The traffic was clearly at 8000 ft, flying wbound, right over phl international. We did what we were supposed to do. I wish ATC had noticed the aircraft sooner. ATC should be made aware that jet aircraft cannot stop climbing on a dime. At best, you might be able to level in 500 ft, but not very smoothly. Overall, I am glad the TCASII system worked so well.

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Original NASA ASRS Text

Title: DURING CLB MLB RECEIVES TCASII RA TO DSND. UNABLE TO STOP CLB PROMPTLY.

Narrative: WX WAS CLR. WE WERE TAKING OFF ON RWY 9L, CLBING TO 5000 FT. AT 2000 FT, WE WERE CLRED TO 10000 FT. WE WERE ON RWY HDG. AT ABOUT 5000 FT WE TURNED TO A HDG OF 360 DEGS. MY CLB RATE WAS ABOUT 2000-3000 FPM. AT 7000 FT WE GOT A TCASII WARNING. IT WAS RIGHT IN THE CTR OF THE SCREEN. WITHIN SECONDS, THE TCASII TOLD US TO DSND. BEFORE THIS POINT, I HAD ALREADY STARTED TO PWR BACK AND NOSE THE PLANE OVER. ATC HAD SAID NOTHING UP TO THIS POINT. BTWN THE 2 TCASII WARNINGS, WE ASKED IF THEY HAD THE TFC. THINGS WERE HAPPENING VERY QUICKLY AT THIS POINT, AND I BELIEVE ATC SAID THEY DID NOT HAVE THE TFC. THE TFC WAS AT 8000 FT. BY THE TIME WE GOT THE WARNING, SPOKE TO ATC, THEN FINALLY SAW THE TFC, I HAD CLBED TO 8500 FT. AT THIS POINT ATC SAYS TO LEVEL AT 8000 FT. I STARTED SLOWLY BACK TOWARD 8000 FT. NOW THAT WE HAD THE TFC IN SIGHT WE ASKED ATC TO CONTINUE CLB TO 10000 FT. THE TFC WAS CLRLY AT 8000 FT, FLYING WBOUND, RIGHT OVER PHL INTL. WE DID WHAT WE WERE SUPPOSED TO DO. I WISH ATC HAD NOTICED THE ACFT SOONER. ATC SHOULD BE MADE AWARE THAT JET ACFT CANNOT STOP CLBING ON A DIME. AT BEST, YOU MIGHT BE ABLE TO LEVEL IN 500 FT, BUT NOT VERY SMOOTHLY. OVERALL, I AM GLAD THE TCASII SYS WORKED SO WELL.

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.