Narrative:

On IFR flight plan. Reported airport in sight. Bay approach cleared us for a visual, turned over to tower. We were cleared to land 19R coming from southeast told to enter on a base leg. Told of aircraft 5 north of field. Never saw aircraft and we did not know he was cleared to land 19L. As I started my base to final in a left descending turn, my first officer asked if I had traffic in sight. It was hard for me to see that direction as the small aircraft was on the right side of aircraft. When I did see him I immediately executed a missed approach in a climbing left turn to enter a left downwind. The small aircraft went below me. Concord is a high density training airport with a training tower and no radar. Supplemental information from acn 187969: reported over the loading docks with ATIS. Was cleared to proceed straight in to 19L. Small aircraft was informed about the small aircraft Y reported looking small aircraft was at 2000 ft. An small transport called in and was cleared for a base entry to 19R.

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Original NASA ASRS Text

Title: CLOSE PROX COMMUTER SMT ON L TURN TO RWY 19R AT CCR AND GA SMA STRAIGHT IN FOR RWY 19L.

Narrative: ON IFR FLT PLAN. RPTED ARPT IN SIGHT. BAY APCH CLRED US FOR A VISUAL, TURNED OVER TO TWR. WE WERE CLRED TO LAND 19R COMING FROM SE TOLD TO ENTER ON A BASE LEG. TOLD OF ACFT 5 N OF FIELD. NEVER SAW ACFT AND WE DID NOT KNOW HE WAS CLRED TO LAND 19L. AS I STARTED MY BASE TO FINAL IN A L DSNDING TURN, MY FO ASKED IF I HAD TFC IN SIGHT. IT WAS HARD FOR ME TO SEE THAT DIRECTION AS THE SMA WAS ON THE R SIDE OF ACFT. WHEN I DID SEE HIM I IMMEDIATELY EXECUTED A MISSED APCH IN A CLBING L TURN TO ENTER A L DOWNWIND. THE SMA WENT BELOW ME. CONCORD IS A HIGH DENSITY TRAINING ARPT WITH A TRAINING TWR AND NO RADAR. SUPPLEMENTAL INFO FROM ACN 187969: RPTED OVER THE LOADING DOCKS WITH ATIS. WAS CLRED TO PROCEED STRAIGHT IN TO 19L. SMA WAS INFORMED ABOUT THE SMA Y RPTED LOOKING SMA WAS AT 2000 FT. AN SMT CALLED IN AND WAS CLRED FOR A BASE ENTRY TO 19R.

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.