Narrative:

All arrival traffic to las was being sequenced to runway 25L. No arrival traffic was being sequenced to runway 19R for the purpose of minimizing potential departure delays. The final radar sector for las vegas TRACON was at full capacity with aircraft on straight-in approachs and aircraft on downwind awaiting sequence into the straight-in flow. Aircraft #1 was turned to a base leg heading in preparation to follow another aircraft to runway 25L. Aircraft #2 was previously cleared for an ILS approach to runway 25L with the intention of later reclring aircraft #2 to follow aircraft #1 visually to runway 25L. As aircraft #1 was turned on base leg; the aircraft that aircraft #1 was to follow had to be vectored off of the final approach course to obtain additional spacing with preceding traffic. Once that confliction was resolved it was then necessary to amend the information contained in the data block of the aircraft that aircraft #1 was to follow. Once that process had been completed; it was then realized that aircraft #2 was in the process of descending on its ILS approach. Although minimum required separation had already been compromised; steps were immediately taken to re-establish minimum required separation.

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Original NASA ASRS Text

Title: L30 CTLR EXPERIENCED OPERROR AT 5700 FT DURING SEQUENCING OF ARR TFC TO RWY 25L RIGHT AFTER A LOSS OF SEPARATION.

Narrative: ALL ARR TFC TO LAS WAS BEING SEQUENCED TO RWY 25L. NO ARR TFC WAS BEING SEQUENCED TO RWY 19R FOR THE PURPOSE OF MINIMIZING POTENTIAL DEP DELAYS. THE FINAL RADAR SECTOR FOR LAS VEGAS TRACON WAS AT FULL CAPACITY WITH ACFT ON STRAIGHT-IN APCHS AND ACFT ON DOWNWIND AWAITING SEQUENCE INTO THE STRAIGHT-IN FLOW. ACFT #1 WAS TURNED TO A BASE LEG HDG IN PREPARATION TO FOLLOW ANOTHER ACFT TO RWY 25L. ACFT #2 WAS PREVIOUSLY CLRED FOR AN ILS APCH TO RWY 25L WITH THE INTENTION OF LATER RECLRING ACFT #2 TO FOLLOW ACFT #1 VISUALLY TO RWY 25L. AS ACFT #1 WAS TURNED ON BASE LEG; THE ACFT THAT ACFT #1 WAS TO FOLLOW HAD TO BE VECTORED OFF OF THE FINAL APCH COURSE TO OBTAIN ADDITIONAL SPACING WITH PRECEDING TFC. ONCE THAT CONFLICTION WAS RESOLVED IT WAS THEN NECESSARY TO AMEND THE INFO CONTAINED IN THE DATA BLOCK OF THE ACFT THAT ACFT #1 WAS TO FOLLOW. ONCE THAT PROCESS HAD BEEN COMPLETED; IT WAS THEN REALIZED THAT ACFT #2 WAS IN THE PROCESS OF DSNDING ON ITS ILS APCH. ALTHOUGH MINIMUM REQUIRED SEPARATION HAD ALREADY BEEN COMPROMISED; STEPS WERE IMMEDIATELY TAKEN TO RE-ESTABLISH MINIMUM REQUIRED SEPARATION.

Data retrieved from NASA's ASRS site as of January 2009 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.