Narrative:

We were descending through FL240 to FL230 and turning right to go direct to the flat rock VOR when we got an RA on our TCASII. It called for an immediate climb. I climbed back up to FL250 where we got the 'clear of conflict' message. We notified ATC immediately and then descended back down to FL230, the altitude we were cleared to descend to. There was an large transport directly below us. I suspect that large transport was climbing to FL220 while we were descending to FL230. We were descending about 1500 FPM, and if they were climbing at that rate, that could have triggered the RA. This is just a possibility because I don't know what altitude the large transport was at.

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Original NASA ASRS Text

Title: FLC OF MLG HAD TCASII RA. CLBED TO CLR THE RA.

Narrative: WE WERE DSNDING THROUGH FL240 TO FL230 AND TURNING R TO GO DIRECT TO THE FLAT ROCK VOR WHEN WE GOT AN RA ON OUR TCASII. IT CALLED FOR AN IMMEDIATE CLB. I CLBED BACK UP TO FL250 WHERE WE GOT THE 'CLR OF CONFLICT' MESSAGE. WE NOTIFIED ATC IMMEDIATELY AND THEN DSNDED BACK DOWN TO FL230, THE ALT WE WERE CLRED TO DSND TO. THERE WAS AN LGT DIRECTLY BELOW US. I SUSPECT THAT LGT WAS CLBING TO FL220 WHILE WE WERE DSNDING TO FL230. WE WERE DSNDING ABOUT 1500 FPM, AND IF THEY WERE CLBING AT THAT RATE, THAT COULD HAVE TRIGGERED THE RA. THIS IS JUST A POSSIBILITY BECAUSE I DON'T KNOW WHAT ALT THE LGT WAS AT.

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.