Narrative:

[We were] cleared down to 12;000 ft by center approaching the airport. Upon leveling at 12;000 we received a RA for conflicting traffic that passed less than a mile at our altitude. No call was received from center. We descended to 11;500 following the commands of the RA. I immediately contacted center to report the near miss. His response made it clear he was aware of the traffic. He reported he was very busy and gave us further descent clearance to 9;000. In near disbelief I explained that being busy is a ridiculous excuse for flying us into a conflict with another aircraft. He apologized and reiterated how busy he was. This is completely unacceptable. This lapse could have caused the loss of both aircraft and numerous lives.

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Original NASA ASRS Text

Title: A B737-800 First Officer reported ATC failed to provide appropriate separation during their descent resulting in a TCAS RA.

Narrative: [We were] cleared down to 12;000 FT by Center approaching the airport. Upon leveling at 12;000 we received a RA for conflicting traffic that passed less than a mile at our altitude. No call was received from Center. We descended to 11;500 following the commands of the RA. I immediately contacted Center to report the near miss. His response made it clear he was aware of the traffic. He reported he was very busy and gave us further descent clearance to 9;000. In near disbelief I explained that being busy is a ridiculous excuse for flying us into a conflict with another aircraft. He apologized and reiterated how busy he was. This is completely unacceptable. This lapse could have caused the loss of both aircraft and numerous lives.

Data retrieved from NASA's ASRS site as of April 2012 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.