Narrative:

We were inbound to sba airport and were handed off from point mugu to sba approach. New controller cleared us for the visual approach to the airport, then immediately issued a TA and advised a right turn. It took a few seconds to visually pick up the other aircraft (a light twin) which was converging from our left at approximately our same altitude. Despite the turn, we were still converging, and I increased the bank and began a rapid climb of 400-500 ft when the other aircraft disappeared from view behind the left wing. The aircraft passed below and to our left, about 300 ft away. The other aircraft was not in contact with approach control at the time of the conflict, and was crossing a common routing from lax to sba. The aircraft did have an encoding altimeter as the controller had given us his altitude just prior to the conflict. The transfer from 1 approach control to another had somehow delayed the issuance of an earlier traffic warning until the moment of immediate conflict. On our part, the first officer had been running through the descent and approach checklists at the moment of handoff, so our concentration had been more inside the cockpit than outside. The other aircraft still would have been very difficult to see even if we had been scanning in his direction, since we were above a solid overcast in somewhat hazy conditions and the other aircraft, a white colored light twin, was slightly below us and blended into the overcast layer.

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Original NASA ASRS Text

Title: AN LTT ACR ACFT HAD AN NMAC WITH AN SMT IN CTLED AIRSPACE.

Narrative: WE WERE INBOUND TO SBA ARPT AND WERE HANDED OFF FROM POINT MUGU TO SBA APCH. NEW CTLR CLRED US FOR THE VISUAL APCH TO THE ARPT, THEN IMMEDIATELY ISSUED A TA AND ADVISED A R TURN. IT TOOK A FEW SECONDS TO VISUALLY PICK UP THE OTHER ACFT (A LIGHT TWIN) WHICH WAS CONVERGING FROM OUR L AT APPROX OUR SAME ALT. DESPITE THE TURN, WE WERE STILL CONVERGING, AND I INCREASED THE BANK AND BEGAN A RAPID CLB OF 400-500 FT WHEN THE OTHER ACFT DISAPPEARED FROM VIEW BEHIND THE L WING. THE ACFT PASSED BELOW AND TO OUR L, ABOUT 300 FT AWAY. THE OTHER ACFT WAS NOT IN CONTACT WITH APCH CTL AT THE TIME OF THE CONFLICT, AND WAS XING A COMMON ROUTING FROM LAX TO SBA. THE ACFT DID HAVE AN ENCODING ALTIMETER AS THE CTLR HAD GIVEN US HIS ALT JUST PRIOR TO THE CONFLICT. THE TRANSFER FROM 1 APCH CTL TO ANOTHER HAD SOMEHOW DELAYED THE ISSUANCE OF AN EARLIER TFC WARNING UNTIL THE MOMENT OF IMMEDIATE CONFLICT. ON OUR PART, THE FO HAD BEEN RUNNING THROUGH THE DSCNT AND APCH CHKLISTS AT THE MOMENT OF HDOF, SO OUR CONCENTRATION HAD BEEN MORE INSIDE THE COCKPIT THAN OUTSIDE. THE OTHER ACFT STILL WOULD HAVE BEEN VERY DIFFICULT TO SEE EVEN IF WE HAD BEEN SCANNING IN HIS DIRECTION, SINCE WE WERE ABOVE A SOLID OVCST IN SOMEWHAT HAZY CONDITIONS AND THE OTHER ACFT, A WHITE COLORED LIGHT TWIN, WAS SLIGHTLY BELOW US AND BLENDED INTO THE OVCST LAYER.

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.