Narrative:

When we were approximately 10-15 NM south of the ccr VOR, travis approach called (I don't recall the exact position) traffic at our approximately 10 O'clock position and about 10 mi indicating 6500 ft last reported as a king air and that he was not talking to the king air. My first officer, the FAA principal operations inspector and myself began searching, and the first officer responded to travis approach that we were looking for the traffic. I adjusted the TCASII to the 10 mi range and confirmed a target in that position indicating -500 ft. A few seconds later the first officer sighted the traffic and pointed it out to me. I told him to report the traffic in sight and he did so. The FAA inspector could not see the traffic because from his perspective the traffic was hidden behind the window post and remained there throughout the encounter. About 45 seconds later it became apparent that the king air was on a converging course due to the lack of lateral movement on the windscreen. I then asked travis approach what our vertical separation was and he responded that he was showing -500 ft and I think he asked us again if we had the traffic in sight and we responded yes we did. As the king air approached us it seemed to me that our vertical separation was actually less than 500 ft and our vertical separation was diminishing rapidly. I guarded the autoplt disconnect switch first then a few seconds later as it became apparent that the separation was going to be unacceptable, I disconnected the autoplt and immediately climbed approximately 80-100 ft just as the king air went out of view in the bottom left corner of my window. I looked down following the aircraft as it passed and caught the RMI in my field of vision as the needles reversed at station passage. In other words we were both directly over the concord VOR at the closest point of convergence. I asked the FAA inspector if he ever saw the aircraft and he responded that he did not but he saw the TCASII indication at the moment I pulled up and said that it indicated -100 ft. I then asked travis what he showed as our vertical separation and he responded just a moment then replied that his radar showed the closest vertical separation as the targets converged as 100 ft as well. I don't recall now whether or not the TCASII was calling out traffic or not. I must have blocked it out if it was doing so.

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Original NASA ASRS Text

Title: NMAC OVER CONCORD, CA.

Narrative: WHEN WE WERE APPROX 10-15 NM S OF THE CCR VOR, TRAVIS APCH CALLED (I DON'T RECALL THE EXACT POS) TFC AT OUR APPROX 10 O'CLOCK POS AND ABOUT 10 MI INDICATING 6500 FT LAST RPTED AS A KING AIR AND THAT HE WAS NOT TALKING TO THE KING AIR. MY FO, THE FAA PRINCIPAL OPS INSPECTOR AND MYSELF BEGAN SEARCHING, AND THE FO RESPONDED TO TRAVIS APCH THAT WE WERE LOOKING FOR THE TFC. I ADJUSTED THE TCASII TO THE 10 MI RANGE AND CONFIRMED A TARGET IN THAT POS INDICATING -500 FT. A FEW SECONDS LATER THE FO SIGHTED THE TFC AND POINTED IT OUT TO ME. I TOLD HIM TO RPT THE TFC IN SIGHT AND HE DID SO. THE FAA INSPECTOR COULD NOT SEE THE TFC BECAUSE FROM HIS PERSPECTIVE THE TFC WAS HIDDEN BEHIND THE WINDOW POST AND REMAINED THERE THROUGHOUT THE ENCOUNTER. ABOUT 45 SECONDS LATER IT BECAME APPARENT THAT THE KING AIR WAS ON A CONVERGING COURSE DUE TO THE LACK OF LATERAL MOVEMENT ON THE WINDSCREEN. I THEN ASKED TRAVIS APCH WHAT OUR VERT SEPARATION WAS AND HE RESPONDED THAT HE WAS SHOWING -500 FT AND I THINK HE ASKED US AGAIN IF WE HAD THE TFC IN SIGHT AND WE RESPONDED YES WE DID. AS THE KING AIR APCHED US IT SEEMED TO ME THAT OUR VERT SEPARATION WAS ACTUALLY LESS THAN 500 FT AND OUR VERT SEPARATION WAS DIMINISHING RAPIDLY. I GUARDED THE AUTOPLT DISCONNECT SWITCH FIRST THEN A FEW SECONDS LATER AS IT BECAME APPARENT THAT THE SEPARATION WAS GOING TO BE UNACCEPTABLE, I DISCONNECTED THE AUTOPLT AND IMMEDIATELY CLBED APPROX 80-100 FT JUST AS THE KING AIR WENT OUT OF VIEW IN THE BOTTOM L CORNER OF MY WINDOW. I LOOKED DOWN FOLLOWING THE ACFT AS IT PASSED AND CAUGHT THE RMI IN MY FIELD OF VISION AS THE NEEDLES REVERSED AT STATION PASSAGE. IN OTHER WORDS WE WERE BOTH DIRECTLY OVER THE CONCORD VOR AT THE CLOSEST POINT OF CONVERGENCE. I ASKED THE FAA INSPECTOR IF HE EVER SAW THE ACFT AND HE RESPONDED THAT HE DID NOT BUT HE SAW THE TCASII INDICATION AT THE MOMENT I PULLED UP AND SAID THAT IT INDICATED -100 FT. I THEN ASKED TRAVIS WHAT HE SHOWED AS OUR VERT SEPARATION AND HE RESPONDED JUST A MOMENT THEN REPLIED THAT HIS RADAR SHOWED THE CLOSEST VERT SEPARATION AS THE TARGETS CONVERGED AS 100 FT AS WELL. I DON'T RECALL NOW WHETHER OR NOT THE TCASII WAS CALLING OUT TFC OR NOT. I MUST HAVE BLOCKED IT OUT IF IT WAS DOING SO.

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.