Narrative:

The loss of standard sep occurred because of controller error. Other actions could have been taken or the actions which were taken could have been taken earlier. It was an example of descending one aircraft below another. Clearance was repeated 3 times before it was acknowledged by the pilot. The pilot was aware of his traffic when it was still 25 mi away and asked to increase his rate of descent. He averaged less than 1000 FPM throughout. The other aircraft, a military flight, took 35 seconds to begin a turn which was issued for sep. While these factors do not absolve the controller of the systems deviation, it must be made clear that we as air traffic controllers rely on prompt action by pilots on a continual basis and especially during traffic situations as this which occur constantly.

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Original NASA ASRS Text

Title: ARTCC CTLR HAD LESS THAN STANDARD SEPARATION WHILE DESCENDING AN MLG THROUGH ALT OF MLT.

Narrative: THE LOSS OF STANDARD SEP OCCURRED BECAUSE OF CTLR ERROR. OTHER ACTIONS COULD HAVE BEEN TAKEN OR THE ACTIONS WHICH WERE TAKEN COULD HAVE BEEN TAKEN EARLIER. IT WAS AN EXAMPLE OF DSNDING ONE ACFT BELOW ANOTHER. CLRNC WAS REPEATED 3 TIMES BEFORE IT WAS ACKNOWLEDGED BY THE PLT. THE PLT WAS AWARE OF HIS TFC WHEN IT WAS STILL 25 MI AWAY AND ASKED TO INCREASE HIS RATE OF DSCNT. HE AVERAGED LESS THAN 1000 FPM THROUGHOUT. THE OTHER ACFT, A MIL FLT, TOOK 35 SECS TO BEGIN A TURN WHICH WAS ISSUED FOR SEP. WHILE THESE FACTORS DO NOT ABSOLVE THE CTLR OF THE SYSTEMS DEVIATION, IT MUST BE MADE CLEAR THAT WE AS AIR TFC CTLRS RELY ON PROMPT ACTION BY PLTS ON A CONTINUAL BASIS AND ESPECIALLY DURING TFC SITUATIONS AS THIS WHICH OCCUR CONSTANTLY.

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.