Narrative:

At FL310, received TA 'traffic' aural warning. ATC called for immediate left descending turn. Simultaneously received RA for descent of +4000 FPM. Captain (PF) complied with both. Leveled at FL290 as instructed by ATC. Neither I nor captain saw the other aircraft. After being instructed to return to FL310, we queried ATC about situation. ATC said an MD80 descending slower than expected.

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Original NASA ASRS Text

Title: CL65 EXPERIENCED TCASII TA RA AND LOSS OF SEPARATION WITH AN MD80 AT FL310 IN ZJX AIRSPACE.

Narrative: AT FL310, RECEIVED TA 'TFC' AURAL WARNING. ATC CALLED FOR IMMEDIATE L DSNDING TURN. SIMULTANEOUSLY RECEIVED RA FOR DSCNT OF +4000 FPM. CAPT (PF) COMPLIED WITH BOTH. LEVELED AT FL290 AS INSTRUCTED BY ATC. NEITHER I NOR CAPT SAW THE OTHER ACFT. AFTER BEING INSTRUCTED TO RETURN TO FL310, WE QUERIED ATC ABOUT SIT. ATC SAID AN MD80 DSNDING SLOWER THAN EXPECTED.

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.