Narrative:

Due to dv movement, airport operations were curtailed for about 30 mins. During this period, a front came through pushing showers and requiring a runway change. At this location, runway changes require fire trucks to enter both ends of both runways to change maia barriers. At time of incident, mlt X had been sent around for an fgt who had not cleared. One runway was unavailable for barrier change. Mlt X entered right closed traffic to follow an mlt Z on 4 mi low approach final. Behind the mlt Z was mlt Y. At the time I made the decision to follow the mlt Z with mlt X, the gap was about 6 mi. Unknown to me, approach control instructed mlt Y to maintain best possible speed on final, so the gap evaporated. I forgot to tell mlt X he was turning inside of an mlt Y (my first mistake). When mlt X turned base, I realized my plan would not work and I told approach to take the mlt Y straight ahead to 1500' (my second mistake) with the intention of landing mlt X. Mlt X was in fact above the mlt Y and when mlt X saw the mlt Y, he turned away from the runway (and toward the mlt Y) and started climbing. Mlt X went over the top of mlt Y. Per their comments at the time, mlt Y and mlt X saw each other and were avoiding each other. Mlt Y reported sep to be about 500'. I feel I was in too big of a hurry to get the maia changes done. I should have held onto my runways until after the rush of traffic that had been held for the dv movements (only about 10-15 mins).

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Original NASA ASRS Text

Title: ATCT LCL CTLR TRIED TO SEQUENCE A SMALL MLT IN BETWEEN 2 MLT ACFT ON FINAL AND CAUSED AN NMAC.

Narrative: DUE TO DV MOVEMENT, ARPT OPS WERE CURTAILED FOR ABOUT 30 MINS. DURING THIS PERIOD, A FRONT CAME THROUGH PUSHING SHOWERS AND REQUIRING A RWY CHANGE. AT THIS LOCATION, RWY CHANGES REQUIRE FIRE TRUCKS TO ENTER BOTH ENDS OF BOTH RWYS TO CHANGE MAIA BARRIERS. AT TIME OF INCIDENT, MLT X HAD BEEN SENT AROUND FOR AN FGT WHO HAD NOT CLRED. ONE RWY WAS UNAVAILABLE FOR BARRIER CHANGE. MLT X ENTERED RIGHT CLOSED TFC TO FOLLOW AN MLT Z ON 4 MI LOW APCH FINAL. BEHIND THE MLT Z WAS MLT Y. AT THE TIME I MADE THE DECISION TO FOLLOW THE MLT Z WITH MLT X, THE GAP WAS ABOUT 6 MI. UNKNOWN TO ME, APCH CTL INSTRUCTED MLT Y TO MAINTAIN BEST POSSIBLE SPD ON FINAL, SO THE GAP EVAPORATED. I FORGOT TO TELL MLT X HE WAS TURNING INSIDE OF AN MLT Y (MY FIRST MISTAKE). WHEN MLT X TURNED BASE, I REALIZED MY PLAN WOULD NOT WORK AND I TOLD APCH TO TAKE THE MLT Y STRAIGHT AHEAD TO 1500' (MY SECOND MISTAKE) WITH THE INTENTION OF LNDG MLT X. MLT X WAS IN FACT ABOVE THE MLT Y AND WHEN MLT X SAW THE MLT Y, HE TURNED AWAY FROM THE RWY (AND TOWARD THE MLT Y) AND STARTED CLBING. MLT X WENT OVER THE TOP OF MLT Y. PER THEIR COMMENTS AT THE TIME, MLT Y AND MLT X SAW EACH OTHER AND WERE AVOIDING EACH OTHER. MLT Y RPTED SEP TO BE ABOUT 500'. I FEEL I WAS IN TOO BIG OF A HURRY TO GET THE MAIA CHANGES DONE. I SHOULD HAVE HELD ONTO MY RWYS UNTIL AFTER THE RUSH OF TFC THAT HAD BEEN HELD FOR THE DV MOVEMENTS (ONLY ABOUT 10-15 MINS).

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.