Narrative:

Air carrier X (hsv-atl) was at 13000 ft MSL. ATC called traffic at 12:30 O'clock and about 8 mi. We called the traffic in sight and ATC told us to 'maintain visual separation' and climb to FL210. We started a slow climb, and 13200 ft TCASII sounded a 'monitor vertical speed' advisory. We descended back to 13000 ft and traffic (aircraft Y) passed to the right about 1/2 mi at 14000 ft. I feel center should have not given us a climb at night with instructions to maintain visual separation and we should not have accepted the clearance as traffic was closer than the first officer and I originally thought. TCASII was a big help in this situation.

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Original NASA ASRS Text

Title: ACR RETURNS TO INITIAL ALT AFTER ACCEPTING VISUAL CLB CLRNC DECIDING THAT HE DID NOT WANT TO CLB WITH XING TFC.

Narrative: ACR X (HSV-ATL) WAS AT 13000 FT MSL. ATC CALLED TFC AT 12:30 O'CLOCK AND ABOUT 8 MI. WE CALLED THE TFC IN SIGHT AND ATC TOLD US TO 'MAINTAIN VISUAL SEPARATION' AND CLB TO FL210. WE STARTED A SLOW CLB, AND 13200 FT TCASII SOUNDED A 'MONITOR VERT SPD' ADVISORY. WE DSNDED BACK TO 13000 FT AND TFC (ACFT Y) PASSED TO THE R ABOUT 1/2 MI AT 14000 FT. I FEEL CTR SHOULD HAVE NOT GIVEN US A CLB AT NIGHT WITH INSTRUCTIONS TO MAINTAIN VISUAL SEPARATION AND WE SHOULD NOT HAVE ACCEPTED THE CLRNC AS TFC WAS CLOSER THAN THE FO AND I ORIGINALLY THOUGHT. TCASII WAS A BIG HELP IN THIS SIT.

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.