Narrative:

After being switched to sjc tower while conducting a visual approach to runway 30L, the local controller issued traffic at 11 O'clock position, 3 mi on left base to runway 29. I was the PNF and responded to this advisory with a 'roger' as we did not have this VFR traffic in sight. When I did finally sight this traffic, we were on about a 1 1/2 mi final to runway 30L at approximately 450-500 ft AGL. The VFR traffic was on a left base to runway 29 approaching our flight path on a 90 degree angle on a direct collision course about 1 mi away at 11 O'clock position. I watched this traffic to make sure he turned final to runway 29 and when he appeared to pass through the runway 29 extended centerline, I became very concerned and asked ATC 'is this guy going to turn final?' they responded by telling the traffic to start a turn to final upon which the pilot entered an immediate very steep turn to the left which took him off the direct collision course that he was on with our aircraft. Had this pilot not turned when he did we would have executed a go around to prevent continued loss of separation. Once it was clear the aircraft was no longer a threat, I commented to the local controller, 'I don't mind telling you that was very disconcerting.' callback conversation with reporter revealed the following information: reporter stated incident was very close to being an near midair collision. Controller at sjc seemed upset that there was so much concern with flight crew about the incident. Controller told the captain it was a see and avoid principle, and he didn't understand what the problem was.

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Original NASA ASRS Text

Title: WHILE ON SHORT FINAL TO SJC ARPT, AN ACR PIC SPOTS TFC ON A BASE LEG TO A PARALLEL RWY APPEARING TO BE OVERSHOOTING AND CONVERGING ON THE AIRLINER.

Narrative: AFTER BEING SWITCHED TO SJC TWR WHILE CONDUCTING A VISUAL APCH TO RWY 30L, THE LCL CTLR ISSUED TFC AT 11 O'CLOCK POS, 3 MI ON L BASE TO RWY 29. I WAS THE PNF AND RESPONDED TO THIS ADVISORY WITH A 'ROGER' AS WE DID NOT HAVE THIS VFR TFC IN SIGHT. WHEN I DID FINALLY SIGHT THIS TFC, WE WERE ON ABOUT A 1 1/2 MI FINAL TO RWY 30L AT APPROX 450-500 FT AGL. THE VFR TFC WAS ON A L BASE TO RWY 29 APCHING OUR FLT PATH ON A 90 DEG ANGLE ON A DIRECT COLLISION COURSE ABOUT 1 MI AWAY AT 11 O'CLOCK POS. I WATCHED THIS TFC TO MAKE SURE HE TURNED FINAL TO RWY 29 AND WHEN HE APPEARED TO PASS THROUGH THE RWY 29 EXTENDED CTRLINE, I BECAME VERY CONCERNED AND ASKED ATC 'IS THIS GUY GOING TO TURN FINAL?' THEY RESPONDED BY TELLING THE TFC TO START A TURN TO FINAL UPON WHICH THE PLT ENTERED AN IMMEDIATE VERY STEEP TURN TO THE L WHICH TOOK HIM OFF THE DIRECT COLLISION COURSE THAT HE WAS ON WITH OUR ACFT. HAD THIS PLT NOT TURNED WHEN HE DID WE WOULD HAVE EXECUTED A GAR TO PREVENT CONTINUED LOSS OF SEPARATION. ONCE IT WAS CLR THE ACFT WAS NO LONGER A THREAT, I COMMENTED TO THE LCL CTLR, 'I DON'T MIND TELLING YOU THAT WAS VERY DISCONCERTING.' CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED INCIDENT WAS VERY CLOSE TO BEING AN NMAC. CTLR AT SJC SEEMED UPSET THAT THERE WAS SO MUCH CONCERN WITH FLC ABOUT THE INCIDENT. CTLR TOLD THE CAPT IT WAS A SEE AND AVOID PRINCIPLE, AND HE DIDN'T UNDERSTAND WHAT THE PROB WAS.

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.