Narrative:

We entered left downwind at 2700' (pattern altitude). We called on the CTAF at 26 mi, 17 mi, 'over west wenatchee,' (about 4 mi) and on entering downwind. The first officer was flying and prior to turning base, I called on CTAF that we were turning left base, and I also cleared the area behind and below us. At about 1/2 mi final I looked to the left and noticed a blue and yellow small aircraft at our altitude at 9 O'clock, approximately 30' away. His flight path was nearly parallel to our own. It looked like he had just completed his turn to final. We initiated a go around and completed the flight. The real lesson here is that one can never let their guard down. It is easy on short final to become focused on the runway, but that can kill you.

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Original NASA ASRS Text

Title: CLOSE PROX COMMUTER-SMT GA-SMA IN TRAFFIC AT NON TWR ARPT.

Narrative: WE ENTERED LEFT DOWNWIND AT 2700' (PATTERN ALT). WE CALLED ON THE CTAF AT 26 MI, 17 MI, 'OVER W WENATCHEE,' (ABOUT 4 MI) AND ON ENTERING DOWNWIND. THE F/O WAS FLYING AND PRIOR TO TURNING BASE, I CALLED ON CTAF THAT WE WERE TURNING LEFT BASE, AND I ALSO CLRED THE AREA BEHIND AND BELOW US. AT ABOUT 1/2 MI FINAL I LOOKED TO THE LEFT AND NOTICED A BLUE AND YELLOW SMA AT OUR ALT AT 9 O'CLOCK, APPROX 30' AWAY. HIS FLT PATH WAS NEARLY PARALLEL TO OUR OWN. IT LOOKED LIKE HE HAD JUST COMPLETED HIS TURN TO FINAL. WE INITIATED A GO AROUND AND COMPLETED THE FLT. THE REAL LESSON HERE IS THAT ONE CAN NEVER LET THEIR GUARD DOWN. IT IS EASY ON SHORT FINAL TO BECOME FOCUSED ON THE RWY, BUT THAT CAN KILL YOU.

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.