Narrative:

Air carrier X approached hailey NDB from the west at 15000 ft MSL. We sighted the hailey airport (10 NM northwest of hle NDB) in cavu WX and requested a visual approach. Slc ARTCC was unable to clear us for the visual because of an air carrier, light transport taxiing out for an IFR departure. I then cancelled IFR and instructed the first officer to descend rapidly to get under the departing light transport aircraft. Normal VFR arrival procedures entail proceeding over the NDB to a point approximately 4 NM east of the NDB with a left turn up the east side of the valley for a straight-in approach to runway 31 at hailey. This keeps us out of the path of departing IFR aircraft who normally proceed out to the NDB and then on course. Our company procedures do not specify crossing altitudes for hle NDB during day VFR operations. During the descent we changed frequency to hailey tower, and I overheard an small aircraft call tower south of hailey for frequency change outbound. I momentarily considered asking tower for his altitude but was more concerned about the light transport. Besides the small aircraft had changed frequency and had said nothing about his altitude or distance from hailey. I assumed he would be 1000-2000 ft AGL. The first officer then called for the approach checklist which I began as we crossed the hle NDB at 8500 ft MSL (+\- 3500 ft AGL). A split second later he yelled 'look!' and threw his arm across my front toward the left. As I jerked around, I saw a brown/yellow single engine small aircraft just ahead of the left wing about 20 ft higher and +\- 50 yards away. We had no time for evasive maneuver, but he began a break to his right as I acquired him. Our TCASII was operational, but no alert was given. He either had no transponder or had failed to turn it on. Tower had not advised us of the outbound traffic nor was he required to. The remainder of the approach and landing was completed without further incident. Tower was informed both on the radio and by telephone after arrival.

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Original NASA ASRS Text

Title: ACR X HAD NMAC WITH SMA. SEE AND AVOID CONCEPT.

Narrative: ACR X APCHED HAILEY NDB FROM THE W AT 15000 FT MSL. WE SIGHTED THE HAILEY ARPT (10 NM NW OF HLE NDB) IN CAVU WX AND REQUESTED A VISUAL APCH. SLC ARTCC WAS UNABLE TO CLR US FOR THE VISUAL BECAUSE OF AN ACR, LTT TAXIING OUT FOR AN IFR DEP. I THEN CANCELLED IFR AND INSTRUCTED THE FO TO DSND RAPIDLY TO GET UNDER THE DEPARTING LTT ACFT. NORMAL VFR ARR PROCS ENTAIL PROCEEDING OVER THE NDB TO A POINT APPROX 4 NM E OF THE NDB WITH A L TURN UP THE E SIDE OF THE VALLEY FOR A STRAIGHT-IN APCH TO RWY 31 AT HAILEY. THIS KEEPS US OUT OF THE PATH OF DEPARTING IFR ACFT WHO NORMALLY PROCEED OUT TO THE NDB AND THEN ON COURSE. OUR COMPANY PROCS DO NOT SPECIFY XING ALTS FOR HLE NDB DURING DAY VFR OPS. DURING THE DSCNT WE CHANGED FREQ TO HAILEY TWR, AND I OVERHEARD AN SMA CALL TWR S OF HAILEY FOR FREQ CHANGE OUTBOUND. I MOMENTARILY CONSIDERED ASKING TWR FOR HIS ALT BUT WAS MORE CONCERNED ABOUT THE LTT. BESIDES THE SMA HAD CHANGED FREQ AND HAD SAID NOTHING ABOUT HIS ALT OR DISTANCE FROM HAILEY. I ASSUMED HE WOULD BE 1000-2000 FT AGL. THE FO THEN CALLED FOR THE APCH CHKLIST WHICH I BEGAN AS WE CROSSED THE HLE NDB AT 8500 FT MSL (+\- 3500 FT AGL). A SPLIT SECOND LATER HE YELLED 'LOOK!' AND THREW HIS ARM ACROSS MY FRONT TOWARD THE L. AS I JERKED AROUND, I SAW A BROWN/YELLOW SINGLE ENG SMA JUST AHEAD OF THE L WING ABOUT 20 FT HIGHER AND +\- 50 YARDS AWAY. WE HAD NO TIME FOR EVASIVE MANEUVER, BUT HE BEGAN A BREAK TO HIS R AS I ACQUIRED HIM. OUR TCASII WAS OPERATIONAL, BUT NO ALERT WAS GIVEN. HE EITHER HAD NO TRANSPONDER OR HAD FAILED TO TURN IT ON. TWR HAD NOT ADVISED US OF THE OUTBOUND TFC NOR WAS HE REQUIRED TO. THE REMAINDER OF THE APCH AND LNDG WAS COMPLETED WITHOUT FURTHER INCIDENT. TWR WAS INFORMED BOTH ON THE RADIO AND BY TELEPHONE AFTER ARR.

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.