Narrative:

After departing lft, we were told to level off at 2000 ft and turn right to a heading of 290 degrees. Once there, were told to turn right to 360 degrees and look for traffic at our 2 O'clock position. The traffic was spotted and we were given clearance to maintain visual separation and climb to 10000 ft. With the traffic at 2 O'clock position and 5 mi, we got a TA. We were climbing at 2500 FPM and then got an RA to 'descend.' the traffic was at our 2 O'clock position moving to 3 O'clock position and passing below us at about 3 mi away. We continued to climb, as descending would have put both aircraft in jeopardy. Now with the aircraft definitely below us, we got the RA of 'descend, descend' and a commanded vsi of 4000 FPM down. The pitch attitude and climb rate were increased to cancel the advisory. The advisory stopped and we continued with a normal climb. We were never queried by ATC. In the future, when 2 aircraft with such different performance capabilities are in close proximity to each other, ATC should wait to issue any further vertical clearance. We should have been left on a heading of 290 degrees, as the traffic would still have been in sight, but would not have produced an alert.

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Original NASA ASRS Text

Title: CL65 FLT CREW CLBS OVER VISUALLY ACQUIRED TFC CONTRARY TO TCASII RA TO DSND, ON DEP FROM LFT.

Narrative: AFTER DEPARTING LFT, WE WERE TOLD TO LEVEL OFF AT 2000 FT AND TURN R TO A HDG OF 290 DEGS. ONCE THERE, WERE TOLD TO TURN R TO 360 DEGS AND LOOK FOR TFC AT OUR 2 O'CLOCK POS. THE TFC WAS SPOTTED AND WE WERE GIVEN CLRNC TO MAINTAIN VISUAL SEPARATION AND CLB TO 10000 FT. WITH THE TFC AT 2 O'CLOCK POS AND 5 MI, WE GOT A TA. WE WERE CLBING AT 2500 FPM AND THEN GOT AN RA TO 'DSND.' THE TFC WAS AT OUR 2 O'CLOCK POS MOVING TO 3 O'CLOCK POS AND PASSING BELOW US AT ABOUT 3 MI AWAY. WE CONTINUED TO CLB, AS DSNDING WOULD HAVE PUT BOTH ACFT IN JEOPARDY. NOW WITH THE ACFT DEFINITELY BELOW US, WE GOT THE RA OF 'DSND, DSND' AND A COMMANDED VSI OF 4000 FPM DOWN. THE PITCH ATTITUDE AND CLB RATE WERE INCREASED TO CANCEL THE ADVISORY. THE ADVISORY STOPPED AND WE CONTINUED WITH A NORMAL CLB. WE WERE NEVER QUERIED BY ATC. IN THE FUTURE, WHEN 2 ACFT WITH SUCH DIFFERENT PERFORMANCE CAPABILITIES ARE IN CLOSE PROX TO EACH OTHER, ATC SHOULD WAIT TO ISSUE ANY FURTHER VERT CLRNC. WE SHOULD HAVE BEEN LEFT ON A HDG OF 290 DEGS, AS THE TFC WOULD STILL HAVE BEEN IN SIGHT, BUT WOULD NOT HAVE PRODUCED AN ALERT.

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.