Narrative:

Departure north/arrival radar 7 combined south flow. WX changing from IFR/VFR. I split arrival radar 7 from departure north. (This was unnecessary since traffic was light.) I vectored aircraft X to 330 degree heading east of dal for sequence to runway 13L ILS. Aircraft Y then stated he had a visual with the airport. I turned him to a 270 degree heading and told him I would have visual approach soon. (I had to pass the runway 15 extended centerline and an MO20 departure off ads before descent.) I heard departure north coordinated with dal tower to keep MO20 at 020 degrees in dal airspace. I turned aircraft Y to 240 degrees after divergence was established with the MO20. At that time departure north climbed the MO20 to 040 degrees as was expected. A satcs then informed me that dal was IFR and vap (visual approach) could not be issued. I checked WX again and dal was broken ceiling 700 ft. (Dal was scattered 700 ft) I looked back to scope, turned aircraft X to 310 degrees (still at 030 degrees) and told him dal was IFR and unable visual approach. Departure north had however turned his MO20 to a 260 degrees which converged with my 240 degree heading. Separation was lost.

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Original NASA ASRS Text

Title: D10 APCH CTLR VECTORING A BE95 FOR VISUAL APCH INTO DAL CONFLICTS WITH MO20 OFF ADS ARPT BEING CTLED BY D10 DEP CTL.

Narrative: DEP N/ARR RADAR 7 COMBINED S FLOW. WX CHANGING FROM IFR/VFR. I SPLIT ARR RADAR 7 FROM DEP N. (THIS WAS UNNECESSARY SINCE TFC WAS LIGHT.) I VECTORED ACFT X TO 330 DEG HDG E OF DAL FOR SEQUENCE TO RWY 13L ILS. ACFT Y THEN STATED HE HAD A VISUAL WITH THE ARPT. I TURNED HIM TO A 270 DEG HDG AND TOLD HIM I WOULD HAVE VISUAL APCH SOON. (I HAD TO PASS THE RWY 15 EXTENDED CTRLINE AND AN MO20 DEP OFF ADS BEFORE DSCNT.) I HEARD DEP N COORDINATED WITH DAL TWR TO KEEP MO20 AT 020 DEGS IN DAL AIRSPACE. I TURNED ACFT Y TO 240 DEGS AFTER DIVERGENCE WAS ESTABLISHED WITH THE MO20. AT THAT TIME DEP N CLBED THE MO20 TO 040 DEGS AS WAS EXPECTED. A SATCS THEN INFORMED ME THAT DAL WAS IFR AND VAP (VISUAL APCH) COULD NOT BE ISSUED. I CHKED WX AGAIN AND DAL WAS BROKEN CEILING 700 FT. (DAL WAS SCATTERED 700 FT) I LOOKED BACK TO SCOPE, TURNED ACFT X TO 310 DEGS (STILL AT 030 DEGS) AND TOLD HIM DAL WAS IFR AND UNABLE VISUAL APCH. DEP N HAD HOWEVER TURNED HIS MO20 TO A 260 DEGS WHICH CONVERGED WITH MY 240 DEG HDG. SEPARATION WAS LOST.

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.