Narrative:

We were flying west and descending to airport traffic pattern altitude of 1400' MSL, and were about 3 mi sse of the airport maneuvering for a standard 45 degree entry to a left downwind leg for a landing on runway 27. I had been monitoring the airport unicom for several mins and heard no radio xmissions. I asked for an airport advisory, and received a reply that the wind favored runway 27. No other information was given. As we arrived at a point about 3 mi sse of the airport, I looked out the left window and saw a single engine low wing small aircraft in a right descending turn and appeared to be in an evasive maneuver to avoid a collision with our aircraft. If the small aircraft Y pilot had announced his position and intentions over the radio, I might have been able to locate him and avoid the near collision. If the small aircraft Y pilot had planned and executed a normal downwind leg traffic pattern entry, we might not have had a conflict. If I had not been directing my attention out the right side of the airplane looking at the airport, and looking for air traffic between us and the airport, I might have seen the small aircraft sooner and in time to avoid the near collision. Recommendations: use the radio to announce your position and intentions. Follow standard procedures when entering an airport traffic pattern.

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Original NASA ASRS Text

Title: TWO SMAS HAVE NMAC DURING TRAFFIC PATTERN ENTRY AT UNCONTROLLED ARPT.

Narrative: WE WERE FLYING W AND DESCENDING TO ARPT TFC PATTERN ALT OF 1400' MSL, AND WERE ABOUT 3 MI SSE OF THE ARPT MANEUVERING FOR A STANDARD 45 DEG ENTRY TO A LEFT DOWNWIND LEG FOR A LNDG ON RWY 27. I HAD BEEN MONITORING THE ARPT UNICOM FOR SEVERAL MINS AND HEARD NO RADIO XMISSIONS. I ASKED FOR AN ARPT ADVISORY, AND RECEIVED A REPLY THAT THE WIND FAVORED RWY 27. NO OTHER INFO WAS GIVEN. AS WE ARRIVED AT A POINT ABOUT 3 MI SSE OF THE ARPT, I LOOKED OUT THE LEFT WINDOW AND SAW A SINGLE ENGINE LOW WING SMA IN A RIGHT DESCENDING TURN AND APPEARED TO BE IN AN EVASIVE MANEUVER TO AVOID A COLLISION WITH OUR ACFT. IF THE SMA Y PLT HAD ANNOUNCED HIS POSITION AND INTENTIONS OVER THE RADIO, I MIGHT HAVE BEEN ABLE TO LOCATE HIM AND AVOID THE NEAR COLLISION. IF THE SMA Y PLT HAD PLANNED AND EXECUTED A NORMAL DOWNWIND LEG TFC PATTERN ENTRY, WE MIGHT NOT HAVE HAD A CONFLICT. IF I HAD NOT BEEN DIRECTING MY ATTN OUT THE RIGHT SIDE OF THE AIRPLANE LOOKING AT THE ARPT, AND LOOKING FOR AIR TFC BETWEEN US AND THE ARPT, I MIGHT HAVE SEEN THE SMA SOONER AND IN TIME TO AVOID THE NEAR COLLISION. RECOMMENDATIONS: USE THE RADIO TO ANNOUNCE YOUR POSITION AND INTENTIONS. FOLLOW STANDARD PROCS WHEN ENTERING AN ARPT TFC PATTERN.

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.