Narrative:

Air carrier Y was given a descent to 5000 ft MSL on initial contact and told to expect ILS 35 approach. There were 2 other aircraft being vectored to the same approach, an MTR and an small transport. The official WX, and the WX information that was displayed on the saids (system atl information display system) and transmitted on the hourly ATIS did not correspond. The WX information I had at my disposal showed a 1000 ft ceiling and visibility of 7 mi with light rain. I took a point out on an aircraft landing at an auxiliary field (ngw) and was concerned about separation between MTR landing ngw and the MTR making practice ILS approachs at crp. At this time crp had a wind shift and changed to runways 13 and 17. The other aircraft involved in the situation, air carrier X, departed crp runway 35 northbound climbing to 6000 ft MSL. I radar idented air carrier X and diverted my attention back to 2 mtrs. I asked the controller who should have been working 1 MTR if that aircraft was in VMC conditions at 1500 ft MSL as our WX was showing a 1000 ft ceiling and the final approach for the MTR was at 2000 ft outside the approach gate. While the other controller tried to obtain this information I vectored air carrier Y to a heading of 250 degrees and amended his altitude to what I thought was 7000 ft. I was reading the flight progress strip of the departing air carrier X climbing to 6000 ft MSL and inadvertently issued air carrier Y descent to 6000 ft. Thinking that would maintain vertical separation. I issued the traffic to air carrier X as 1 O'clock 7 mi wbound medium large transport descending to 7000 ft thinking that is what I had issued. I diverted my attention back to the 2 mtrs south of crp. The pilot of air carrier Y asked if he had traffic off his nose, and I asked him to verify he was at 7000 ft MSL. Air carrier Y said he was at 6000 ft. I issued the traffic and an immediate descent to air carrier Y. The pilot said he had visual separation.

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Original NASA ASRS Text

Title: ACR Y INADVERTENTLY CLRED TO OCCUPIED ALT HAD LTSS FROM ACR X. SYS ERROR.

Narrative: ACR Y WAS GIVEN A DSCNT TO 5000 FT MSL ON INITIAL CONTACT AND TOLD TO EXPECT ILS 35 APCH. THERE WERE 2 OTHER ACFT BEING VECTORED TO THE SAME APCH, AN MTR AND AN SMT. THE OFFICIAL WX, AND THE WX INFO THAT WAS DISPLAYED ON THE SAIDS (SYS ATL INFO DISPLAY SYS) AND XMITTED ON THE HRLY ATIS DID NOT CORRESPOND. THE WX INFO I HAD AT MY DISPOSAL SHOWED A 1000 FT CEILING AND VISIBILITY OF 7 MI WITH LIGHT RAIN. I TOOK A POINT OUT ON AN ACFT LNDG AT AN AUX FIELD (NGW) AND WAS CONCERNED ABOUT SEPARATION BTWN MTR LNDG NGW AND THE MTR MAKING PRACTICE ILS APCHS AT CRP. AT THIS TIME CRP HAD A WIND SHIFT AND CHANGED TO RWYS 13 AND 17. THE OTHER ACFT INVOLVED IN THE SITUATION, ACR X, DEPARTED CRP RWY 35 NBOUND CLBING TO 6000 FT MSL. I RADAR IDENTED ACR X AND DIVERTED MY ATTN BACK TO 2 MTRS. I ASKED THE CTLR WHO SHOULD HAVE BEEN WORKING 1 MTR IF THAT ACFT WAS IN VMC CONDITIONS AT 1500 FT MSL AS OUR WX WAS SHOWING A 1000 FT CEILING AND THE FINAL APCH FOR THE MTR WAS AT 2000 FT OUTSIDE THE APCH GATE. WHILE THE OTHER CTLR TRIED TO OBTAIN THIS INFO I VECTORED ACR Y TO A HDG OF 250 DEGS AND AMENDED HIS ALT TO WHAT I THOUGHT WAS 7000 FT. I WAS READING THE FLT PROGRESS STRIP OF THE DEPARTING ACR X CLBING TO 6000 FT MSL AND INADVERTENTLY ISSUED ACR Y DSCNT TO 6000 FT. THINKING THAT WOULD MAINTAIN VERT SEPARATION. I ISSUED THE TFC TO ACR X AS 1 O'CLOCK 7 MI WBOUND MLG DSNDING TO 7000 FT THINKING THAT IS WHAT I HAD ISSUED. I DIVERTED MY ATTN BACK TO THE 2 MTRS S OF CRP. THE PLT OF ACR Y ASKED IF HE HAD TFC OFF HIS NOSE, AND I ASKED HIM TO VERIFY HE WAS AT 7000 FT MSL. ACR Y SAID HE WAS AT 6000 FT. I ISSUED THE TFC AND AN IMMEDIATE DSCNT TO ACR Y. THE PLT SAID HE HAD VISUAL SEPARATION.

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.