Narrative:

We had been cleared to descend to 5000' MSL by bay approach (135.4) on a 240 degree heading to intercept the localizer to oak runway 29. Approach control asked our altitude as we approached 8000' MSL, and I answered, 'passing 8000'.' approach control said, 'traffic at 1 O'clock, 4 mi, 7200'.' I said to the first officer, 'let's level off,' and he leveled off after disconnecting the autoplt. As we leveled off at about 7600', the first officer said, 'there he is!', and we both applied aileron control for an abrupt right bank to miss the aircraft. He was at our 12:30 position, same altitude, and heading approximately 120 degrees. The aircraft was a white light twin with blue stripe(south), low wing with winglets, that passed about 200' off our nose with no evasive action of his own. I feel confident we would have collided west/O evasive action. During conversation (after landing at oak) with TRACON supervisor, he was dissatisfied that the controller had not handled the conflict differently because they had been talking to the other aircraft. My opinion was that the traffic should have been called to us first and/or an instruction to level off, rather than first requesting our altitude. Apparently, intermittent data blocks on the controller's screen made it unclear as to the conflict. More aggressive controller action could have negated the need for abrupt evasive action, which was the only factor in avoiding a catastrophe.

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Original NASA ASRS Text

Title: ABRUPT EVASIVE ACTION REQUIRED BY ACR MLG FLT CREW TO AVOID COLLISION WITH LIGHT TWIN, OPPOSITE DIRECTION.

Narrative: WE HAD BEEN CLRED TO DSND TO 5000' MSL BY BAY APCH (135.4) ON A 240 DEG HDG TO INTERCEPT THE LOC TO OAK RWY 29. APCH CTL ASKED OUR ALT AS WE APCHED 8000' MSL, AND I ANSWERED, 'PASSING 8000'.' APCH CTL SAID, 'TFC AT 1 O'CLOCK, 4 MI, 7200'.' I SAID TO THE F/O, 'LET'S LEVEL OFF,' AND HE LEVELED OFF AFTER DISCONNECTING THE AUTOPLT. AS WE LEVELED OFF AT ABOUT 7600', THE F/O SAID, 'THERE HE IS!', AND WE BOTH APPLIED AILERON CONTROL FOR AN ABRUPT RIGHT BANK TO MISS THE ACFT. HE WAS AT OUR 12:30 POS, SAME ALT, AND HDG APPROX 120 DEGS. THE ACFT WAS A WHITE LIGHT TWIN WITH BLUE STRIPE(S), LOW WING WITH WINGLETS, THAT PASSED ABOUT 200' OFF OUR NOSE WITH NO EVASIVE ACTION OF HIS OWN. I FEEL CONFIDENT WE WOULD HAVE COLLIDED W/O EVASIVE ACTION. DURING CONVERSATION (AFTER LNDG AT OAK) WITH TRACON SUPVR, HE WAS DISSATISFIED THAT THE CTLR HAD NOT HANDLED THE CONFLICT DIFFERENTLY BECAUSE THEY HAD BEEN TALKING TO THE OTHER ACFT. MY OPINION WAS THAT THE TFC SHOULD HAVE BEEN CALLED TO US FIRST AND/OR AN INSTRUCTION TO LEVEL OFF, RATHER THAN FIRST REQUESTING OUR ALT. APPARENTLY, INTERMITTENT DATA BLOCKS ON THE CTLR'S SCREEN MADE IT UNCLEAR AS TO THE CONFLICT. MORE AGGRESSIVE CTLR ACTION COULD HAVE NEGATED THE NEED FOR ABRUPT EVASIVE ACTION, WHICH WAS THE ONLY FACTOR IN AVOIDING A CATASTROPHE.

Data retrieved from NASA's ASRS site as of August 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.