Narrative:

Approaching smf, flunk 3 arrival. Came off tenco on a 255 degree heading. Taken through final approach course for 16L. Given a 270 degree right turn around to final. In roughly the 'base leg' turn, given a 180 degree heading to intercept the NDB 16L approach and cleared to 1800'. Also asked to slow to final approach speed for traffic flow. Told we were 6 mi from 'metre'. Several mins later, we were given traffic 1-2 O'clock 1 mi eastbound unconfirmed 2000'. Within seconds, controller advised climb immediately to 2500', traffic converging and not in contact. I did as advised. Traffic passed directly below us (2000' appeared to be a good altitude). We were at 2000' when I initiated climb back to 2500'. Smf was a first time airport for both crew members. The overhead 270 degree turn to the NDB was not anticipated so as a result I was hand flying and head down in the cockpit. The first officer was busy with my commands for gear, flaps, speeds, etc and radios, and checklists whether we would have seen the traffic in time I don't know. I honestly feel that the controllers vigilance and actions prevented what would have been (at the least) a very close call. Because I was under 10000', I had the wing ice lights, the ground flood lights, and the main landing lights all on. Because I was slowed to minimum approach speed, I was gear down going to flaps 40. I believe I also had the nose gear taxi and landing lights on. Believe the position of the conflict to be about 2-3 mi outside (north) of the 'metre' NDB. Other aircraft appeared to be on order of a straight tail small aircraft.

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Original NASA ASRS Text

Title: CLOSE PROX ACR-MLG GA-SMA. SMA IN SMF ARSA WITHOUT RADIO CONTACT.

Narrative: APCHING SMF, FLUNK 3 ARR. CAME OFF TENCO ON A 255 DEG HDG. TAKEN THROUGH FINAL APCH COURSE FOR 16L. GIVEN A 270 DEG R TURN AROUND TO FINAL. IN ROUGHLY THE 'BASE LEG' TURN, GIVEN A 180 DEG HDG TO INTERCEPT THE NDB 16L APCH AND CLRED TO 1800'. ALSO ASKED TO SLOW TO FINAL APCH SPD FOR TFC FLOW. TOLD WE WERE 6 MI FROM 'METRE'. SEVERAL MINS LATER, WE WERE GIVEN TFC 1-2 O'CLOCK 1 MI EBND UNCONFIRMED 2000'. WITHIN SECS, CTLR ADVISED CLB IMMEDIATELY TO 2500', TFC CONVERGING AND NOT IN CONTACT. I DID AS ADVISED. TFC PASSED DIRECTLY BELOW US (2000' APPEARED TO BE A GOOD ALT). WE WERE AT 2000' WHEN I INITIATED CLB BACK TO 2500'. SMF WAS A FIRST TIME ARPT FOR BOTH CREW MEMBERS. THE OVERHEAD 270 DEG TURN TO THE NDB WAS NOT ANTICIPATED SO AS A RESULT I WAS HAND FLYING AND HEAD DOWN IN THE COCKPIT. THE F/O WAS BUSY WITH MY COMMANDS FOR GEAR, FLAPS, SPDS, ETC AND RADIOS, AND CHKLISTS WHETHER WE WOULD HAVE SEEN THE TFC IN TIME I DON'T KNOW. I HONESTLY FEEL THAT THE CTLRS VIGILANCE AND ACTIONS PREVENTED WHAT WOULD HAVE BEEN (AT THE LEAST) A VERY CLOSE CALL. BECAUSE I WAS UNDER 10000', I HAD THE WING ICE LIGHTS, THE GND FLOOD LIGHTS, AND THE MAIN LNDG LIGHTS ALL ON. BECAUSE I WAS SLOWED TO MINIMUM APCH SPD, I WAS GEAR DOWN GOING TO FLAPS 40. I BELIEVE I ALSO HAD THE NOSE GEAR TAXI AND LNDG LIGHTS ON. BELIEVE THE POS OF THE CONFLICT TO BE ABOUT 2-3 MI OUTSIDE (N) OF THE 'METRE' NDB. OTHER ACFT APPEARED TO BE ON ORDER OF A STRAIGHT TAIL SMA.

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.