Narrative:

On may/xa/98 I had an operational error. The conflict alert did not activate until separation was actually lost. Both data blocks were in flat track and the altitude information was entered correctly on both. Our conflict alert is so overly sensitive that it routinely goes off with a departure and an overflt that are separated by 30000 ft or more. When the conflict alert did not activate it created a false sense of security. I hesitated and thought, well, the computer thinks it will work, then re-evaluated and took corrective action to solve the error. Our quality assurance office insisted that according to their data, conflict alert activated seconds prior to my reaction to correct it. Another controller witnessed this error and agrees and supports my statement that conflict alert did not activate until it was less than 5 mi. We can't trust and use conflict alert if it is this unreliable. We tend to overlook it sometimes since it goes off so often unnecessarily and yet fails us as a backup tool when we make an error and need it.

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Original NASA ASRS Text

Title: ARTCC CTLR SECOND GUESSES CTL ACTIONS TOO LATE AND ALLOWS DSNDING SF340 TO CONFLICT WITH ENRTE B737. CTLR QUESTIONS CONFLICT ALERT FUNCTION AND CHALLENGES FACILITY QUALITY ASSURANCE PERSONNEL ABOUT RADAR SYS, CONFLICT ALERT, RELIABILITY.

Narrative: ON MAY/XA/98 I HAD AN OPERROR. THE CONFLICT ALERT DID NOT ACTIVATE UNTIL SEPARATION WAS ACTUALLY LOST. BOTH DATA BLOCKS WERE IN FLAT TRACK AND THE ALT INFO WAS ENTERED CORRECTLY ON BOTH. OUR CONFLICT ALERT IS SO OVERLY SENSITIVE THAT IT ROUTINELY GOES OFF WITH A DEP AND AN OVERFLT THAT ARE SEPARATED BY 30000 FT OR MORE. WHEN THE CONFLICT ALERT DID NOT ACTIVATE IT CREATED A FALSE SENSE OF SECURITY. I HESITATED AND THOUGHT, WELL, THE COMPUTER THINKS IT WILL WORK, THEN RE-EVALUATED AND TOOK CORRECTIVE ACTION TO SOLVE THE ERROR. OUR QUALITY ASSURANCE OFFICE INSISTED THAT ACCORDING TO THEIR DATA, CONFLICT ALERT ACTIVATED SECONDS PRIOR TO MY REACTION TO CORRECT IT. ANOTHER CTLR WITNESSED THIS ERROR AND AGREES AND SUPPORTS MY STATEMENT THAT CONFLICT ALERT DID NOT ACTIVATE UNTIL IT WAS LESS THAN 5 MI. WE CAN'T TRUST AND USE CONFLICT ALERT IF IT IS THIS UNRELIABLE. WE TEND TO OVERLOOK IT SOMETIMES SINCE IT GOES OFF SO OFTEN UNNECESSARILY AND YET FAILS US AS A BACKUP TOOL WHEN WE MAKE AN ERROR AND NEED IT.

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.