Narrative:

Aircraft X on downwind vector descending from 8000 ft to 5000 ft at 210 KTS for ILS runway 30L being worked by south approach control. Aircraft Y on base leg level at 5000 ft being worked by north approach control for ILS runway 30R. The south approach controller was the 'low' side (aircraft at 3000 ft or 4000 ft at localizer intercept) and the north approach controller was the high side (aircraft at 5000 ft or above at localizer intercept). Aircraft X turned to 040 degrees (base leg) heading and descended to 3000 ft. The initial clearance to 3000 ft was partially blocked by another aircraft checking on the frequency, and the clearance to 3000 ft had to be restated, and was acknowledged by aircraft X. 6 seconds later aircraft X was told to expedite descent to 3000 ft. 11 seconds later aircraft X was issued heading of right turn to 150 degrees, expedite descent to 3000 ft, traffic at 12 O'clock position, 5 mi. Aircraft Y was level at 5000 ft being vectored through the runway 30R localizer for spacing with other traffic ahead on the localizer. 32 seconds had passed since aircraft X was initially issued descent to 3000 ft. Aircraft X was still at 5000 ft when evasive action was taken, when aircraft X was turned to 150 degrees by south approach, aircraft Y was turned from 220 degrees to 340 degrees by north approach. Both aircraft reported TCASII alerts with aircraft X advised to climb and aircraft Y advised to descend. The TCASII alerts were opposite of what the controllers were trying to do. The south approach controller was decertified because of loss of separation, faah 7110.65 paragraph 5-5-3. This occurred at the beginning of an inbound rush. The ILS stagger was being established with 6 aircraft on the south approach frequency and 2 aircraft on the north approach frequency. The south approach controller was training a low time developmental. The distance aircraft Y was vectored through the localizer was further than anticipated by the south approach controller, so a misjudgement was made when aircraft X was turned to the base leg. Aircraft X did not descend as anticipated.

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Original NASA ASRS Text

Title: 2 FINAL CTLRS WORKING TFC TO PARALLEL RWYS AT MSP MISCUE ON RESPECTIVE BASE LEGS AND LOSE STANDARD SEPARATION.

Narrative: ACFT X ON DOWNWIND VECTOR DSNDING FROM 8000 FT TO 5000 FT AT 210 KTS FOR ILS RWY 30L BEING WORKED BY S APCH CTL. ACFT Y ON BASE LEG LEVEL AT 5000 FT BEING WORKED BY N APCH CTL FOR ILS RWY 30R. THE S APCH CTLR WAS THE 'LOW' SIDE (ACFT AT 3000 FT OR 4000 FT AT LOC INTERCEPT) AND THE N APCH CTLR WAS THE HIGH SIDE (ACFT AT 5000 FT OR ABOVE AT LOC INTERCEPT). ACFT X TURNED TO 040 DEGS (BASE LEG) HEADING AND DSNDED TO 3000 FT. THE INITIAL CLRNC TO 3000 FT WAS PARTIALLY BLOCKED BY ANOTHER ACFT CHKING ON THE FREQ, AND THE CLRNC TO 3000 FT HAD TO BE RESTATED, AND WAS ACKNOWLEDGED BY ACFT X. 6 SECONDS LATER ACFT X WAS TOLD TO EXPEDITE DSCNT TO 3000 FT. 11 SECONDS LATER ACFT X WAS ISSUED HEADING OF R TURN TO 150 DEGS, EXPEDITE DSCNT TO 3000 FT, TFC AT 12 O'CLOCK POS, 5 MI. ACFT Y WAS LEVEL AT 5000 FT BEING VECTORED THROUGH THE RWY 30R LOC FOR SPACING WITH OTHER TFC AHEAD ON THE LOC. 32 SECONDS HAD PASSED SINCE ACFT X WAS INITIALLY ISSUED DSCNT TO 3000 FT. ACFT X WAS STILL AT 5000 FT WHEN EVASIVE ACTION WAS TAKEN, WHEN ACFT X WAS TURNED TO 150 DEGS BY S APCH, ACFT Y WAS TURNED FROM 220 DEGS TO 340 DEGS BY N APCH. BOTH ACFT RPTED TCASII ALERTS WITH ACFT X ADVISED TO CLB AND ACFT Y ADVISED TO DSND. THE TCASII ALERTS WERE OPPOSITE OF WHAT THE CTLRS WERE TRYING TO DO. THE S APCH CTLR WAS DECERTIFIED BECAUSE OF LOSS OF SEPARATION, FAAH 7110.65 PARAGRAPH 5-5-3. THIS OCCURRED AT THE BEGINNING OF AN INBOUND RUSH. THE ILS STAGGER WAS BEING ESTABLISHED WITH 6 ACFT ON THE S APCH FREQ AND 2 ACFT ON THE N APCH FREQ. THE S APCH CTLR WAS TRAINING A LOW TIME DEVELOPMENTAL. THE DISTANCE ACFT Y WAS VECTORED THROUGH THE LOC WAS FURTHER THAN ANTICIPATED BY THE S APCH CTLR, SO A MISJUDGEMENT WAS MADE WHEN ACFT X WAS TURNED TO THE BASE LEG. ACFT X DID NOT DSND AS ANTICIPATED.

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.