Narrative:

I was operating the north approach control position at msp TRACON during the noon rush. Air carrier X checked in at 4000', heading 150 degrees, from north satellite control. I acknowledged. I then proceeded to issue control instructions to air carrier Y. 5 mins later I instructed air carrier Y to turn right heading 270 degrees and descend from 5000 to 4000'. I then went on to issue instructions to other aircraft. Then the south arrival control pointed out to me that air carrier X was in the way of air carrier Y. I immediately issued air carrier X a turn to avoid air carrier Y and began issuing traffic. Initially my transmission was blocked by another aircraft. I reissued traffic and a turn to air carrier X and it was acknowledged. I instructed air carrier X to maintain visibility sep. I made the mistake of forgetting about air carrier Y while my attention was focused on the final trying to fill gaps with aircraft on the downwind. My focus became narrowed as the gaps became harder to fill. The gaps became hard to fill because of a strong north wind that made vectoring hard. Also the erratic final by the south arrival controller (a trnee), for which I had to make erratic turns to match the south arrival controller. Also the lack of a feeder controller operating the far fix traffic also diverted my attention. The procedure of satellite control of handing traffic to arrival on conflicting heading and altitudes is a contributing factor.

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Original NASA ASRS Text

Title: ACFT DESCENDED TO SAME ALT AS CONVERGING TRAFFIC.

Narrative: I WAS OPERATING THE N APCH CTL POS AT MSP TRACON DURING THE NOON RUSH. ACR X CHKED IN AT 4000', HDG 150 DEGS, FROM N SATELLITE CTL. I ACKNOWLEDGED. I THEN PROCEEDED TO ISSUE CTL INSTRUCTIONS TO ACR Y. 5 MINS LATER I INSTRUCTED ACR Y TO TURN RIGHT HDG 270 DEGS AND DSND FROM 5000 TO 4000'. I THEN WENT ON TO ISSUE INSTRUCTIONS TO OTHER ACFT. THEN THE S ARR CTL POINTED OUT TO ME THAT ACR X WAS IN THE WAY OF ACR Y. I IMMEDIATELY ISSUED ACR X A TURN TO AVOID ACR Y AND BEGAN ISSUING TFC. INITIALLY MY XMISSION WAS BLOCKED BY ANOTHER ACFT. I REISSUED TFC AND A TURN TO ACR X AND IT WAS ACKNOWLEDGED. I INSTRUCTED ACR X TO MAINTAIN VIS SEP. I MADE THE MISTAKE OF FORGETTING ABOUT ACR Y WHILE MY ATTN WAS FOCUSED ON THE FINAL TRYING TO FILL GAPS WITH ACFT ON THE DOWNWIND. MY FOCUS BECAME NARROWED AS THE GAPS BECAME HARDER TO FILL. THE GAPS BECAME HARD TO FILL BECAUSE OF A STRONG N WIND THAT MADE VECTORING HARD. ALSO THE ERRATIC FINAL BY THE S ARR CTLR (A TRNEE), FOR WHICH I HAD TO MAKE ERRATIC TURNS TO MATCH THE S ARR CTLR. ALSO THE LACK OF A FEEDER CTLR OPERATING THE FAR FIX TFC ALSO DIVERTED MY ATTN. THE PROC OF SATELLITE CTL OF HANDING TFC TO ARR ON CONFLICTING HDG AND ALTS IS A CONTRIBUTING FACTOR.

Data retrieved from NASA's ASRS site as of August 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.