Narrative:

Small aircraft was approaching palmdale VORTAC from the east at 12000' MSL. Medium large transport was descending to 80 north of small aircraft westbound and was cleared direct pmd by the controller prior to descending below small aircraft. Route and altitudes merged over pmd VORTAC. Pilot of the small aircraft reported the medium large transport at 1/4 mi laterally and same altitude. Small aircraft declared a near midair collision. During the mins immediately prior to the incident the controller's attention had been occupied by, and rapid coordination and instructions issued to resolve, a conflict created by the air traffic facility handing off medium large transport. Training was in progress and no handoff controller was available to assist in this coordination. Although a supervisor was monitoring from the overhead console, the erroneous clearance was not perceived by the supervisor, the trnee or the controller issuing the clearance. Additional controllers arriving at work had been instructed to open additional sectors instead of assisting at sectors already open with developing traffic. Edwards RAPCON lack of automated equipment provides no 'conflict alert' data.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION OCCURRED BETWEEN AN ENROUTE ACFT AND AN ACFT DESCENDING TO LAND AT ARPT OF DESTINATION.

Narrative: SMA WAS APCHING PALMDALE VORTAC FROM THE E AT 12000' MSL. MLG WAS DSNDING TO 80 N OF SMA WBND AND WAS CLRED DIRECT PMD BY THE CTLR PRIOR TO DSNDING BELOW SMA. RTE AND ALTS MERGED OVER PMD VORTAC. PLT OF THE SMA RPTED THE MLG AT 1/4 MI LATERALLY AND SAME ALT. SMA DECLARED A NMAC. DURING THE MINS IMMEDIATELY PRIOR TO THE INCIDENT THE CTLR'S ATTN HAD BEEN OCCUPIED BY, AND RAPID COORD AND INSTRUCTIONS ISSUED TO RESOLVE, A CONFLICT CREATED BY THE AIR TFC FAC HANDING OFF MLG. TRNING WAS IN PROGRESS AND NO HDOF CTLR WAS AVAILABLE TO ASSIST IN THIS COORD. ALTHOUGH A SUPVR WAS MONITORING FROM THE OVERHEAD CONSOLE, THE ERRONEOUS CLRNC WAS NOT PERCEIVED BY THE SUPVR, THE TRNEE OR THE CTLR ISSUING THE CLRNC. ADDITIONAL CTLRS ARRIVING AT WORK HAD BEEN INSTRUCTED TO OPEN ADDITIONAL SECTORS INSTEAD OF ASSISTING AT SECTORS ALREADY OPEN WITH DEVELOPING TFC. EDWARDS RAPCON LACK OF AUTOMATED EQUIP PROVIDES NO 'CONFLICT ALERT' DATA.

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.