Narrative:

On departure clearance from hsv-atl, we (aircraft X) were held at 13000 ft for crossing traffic. Then ATC asked if we had a fokker 27 (aircraft Y) in sight at 14000 ft, 1-2 O'clock position, sbound. We advised we had visual contact. Then ATC cleared us climb to FL210 (from 13000 ft MSL), 'maintain visual contact.' TCASII was on 40 NM range, traffic visual, with both pilots and traffic at 1-2 O'clock, 10 mi on TCASII. Captain started climb 500 ft vvi for FL210, flying manually. I performed PNF duties, then looked up to maintain visual separation. I saw traffic at 12 O'clock, told captain to stop climb and descend to 13000 ft MSL. He complied, noticing the nose-to-nose position with TCASII stating 'monitor vertical climb' and aircraft passing 13280 ft MSL. He descended immediately to 13000 ft MSL. We noticed the traffic had its landing light on and out now and passed underneath it with 1 NM separation +1000 ft vertical clearance. Traffic and ATC said nothing. The sky was dark, sky clear, no obscuration, unlimited visibility in-flight, and traffic was clearly visible to me. We should have waited to start our climb when traffic was past us. In retrospect, our 100% IFR flying and emphasis on ATC rtes and handling, should be a flag of caution when given a clearance like this.

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Original NASA ASRS Text

Title: MD88 FLC ACCEPTS VISUAL CLB CLRNC TO MAINTAIN VISUAL SEPARATION FROM ENRTE F27. AFTER INITIATING CLB, MD88 CHANGES THEIR MIND, DSNDING BACK TO ORIGINAL ALT, CLBING AFTER TFC PASSES.

Narrative: ON DEP CLRNC FROM HSV-ATL, WE (ACFT X) WERE HELD AT 13000 FT FOR XING TFC. THEN ATC ASKED IF WE HAD A FOKKER 27 (ACFT Y) IN SIGHT AT 14000 FT, 1-2 O'CLOCK POS, SBOUND. WE ADVISED WE HAD VISUAL CONTACT. THEN ATC CLRED US CLB TO FL210 (FROM 13000 FT MSL), 'MAINTAIN VISUAL CONTACT.' TCASII WAS ON 40 NM RANGE, TFC VISUAL, WITH BOTH PLTS AND TFC AT 1-2 O'CLOCK, 10 MI ON TCASII. CAPT STARTED CLB 500 FT VVI FOR FL210, FLYING MANUALLY. I PERFORMED PNF DUTIES, THEN LOOKED UP TO MAINTAIN VISUAL SEPARATION. I SAW TFC AT 12 O'CLOCK, TOLD CAPT TO STOP CLB AND DSND TO 13000 FT MSL. HE COMPLIED, NOTICING THE NOSE-TO-NOSE POS WITH TCASII STATING 'MONITOR VERT CLB' AND ACFT PASSING 13280 FT MSL. HE DSNDED IMMEDIATELY TO 13000 FT MSL. WE NOTICED THE TFC HAD ITS LNDG LIGHT ON AND OUT NOW AND PASSED UNDERNEATH IT WITH 1 NM SEPARATION +1000 FT VERT CLRNC. TFC AND ATC SAID NOTHING. THE SKY WAS DARK, SKY CLR, NO OBSCURATION, UNLIMITED VISIBILITY INFLT, AND TFC WAS CLRLY VISIBLE TO ME. WE SHOULD HAVE WAITED TO START OUR CLB WHEN TFC WAS PAST US. IN RETROSPECT, OUR 100% IFR FLYING AND EMPHASIS ON ATC RTES AND HANDLING, SHOULD BE A FLAG OF CAUTION WHEN GIVEN A CLRNC LIKE THIS.

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.