Narrative:

After being cleared for the VOR 27 approach into osh, chicago center handed us off to osh tower. At this point on our flight we were in IMC conditions at 2800' MSL 8 DME east of osh VOR on the centerline of the VOR 27 approach. In response to our initial call the osh tower cleared us to land and advised us of a VFR small aircraft east of the airport, eastbound, and that the small aircraft was told to stay well clear of the approach course. In response to that information I double checked that all of our anticollision, landing and taxi lights were on. Shortly after breaking out of the clouds the first officer stated he had the small aircraft and began a hard left turn to avoid the other plane. At that point I saw the other aircraft coming at us in a left bank, trying to avoid us. After passing the small aircraft we continued the approach and landed normally. The problem arose due to the mixing of IFR and VFR traffic in marginal VFR conditions. Listening to the other pilot on the radio she sounded inexperienced and confused. So, even though she was told to stay clear of the approach course, I can't help but wonder if she even knew what and where that was. Osh tower is only a VFR facility and therefore has limited capabilities, but giving a suggested heading for a given distance to ensure sep could have avoided the whole situation. If the small aircraft had maintained 500' below the ceiling, we would have had more time to see and avoid.

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Original NASA ASRS Text

Title: NMAC BETWEEN ACR-MDT ON APCH AND GA-SMA IN PATTERN.

Narrative: AFTER BEING CLRED FOR THE VOR 27 APCH INTO OSH, CHICAGO CENTER HANDED US OFF TO OSH TWR. AT THIS POINT ON OUR FLT WE WERE IN IMC CONDITIONS AT 2800' MSL 8 DME E OF OSH VOR ON THE CENTERLINE OF THE VOR 27 APCH. IN RESPONSE TO OUR INITIAL CALL THE OSH TWR CLRED US TO LAND AND ADVISED US OF A VFR SMA E OF THE ARPT, EBND, AND THAT THE SMA WAS TOLD TO STAY WELL CLR OF THE APCH COURSE. IN RESPONSE TO THAT INFO I DOUBLE CHKED THAT ALL OF OUR ANTICOLLISION, LNDG AND TAXI LIGHTS WERE ON. SHORTLY AFTER BREAKING OUT OF THE CLOUDS THE F/O STATED HE HAD THE SMA AND BEGAN A HARD LEFT TURN TO AVOID THE OTHER PLANE. AT THAT POINT I SAW THE OTHER ACFT COMING AT US IN A LEFT BANK, TRYING TO AVOID US. AFTER PASSING THE SMA WE CONTINUED THE APCH AND LANDED NORMALLY. THE PROB AROSE DUE TO THE MIXING OF IFR AND VFR TFC IN MARGINAL VFR CONDITIONS. LISTENING TO THE OTHER PLT ON THE RADIO SHE SOUNDED INEXPERIENCED AND CONFUSED. SO, EVEN THOUGH SHE WAS TOLD TO STAY CLR OF THE APCH COURSE, I CAN'T HELP BUT WONDER IF SHE EVEN KNEW WHAT AND WHERE THAT WAS. OSH TWR IS ONLY A VFR FAC AND THEREFORE HAS LIMITED CAPABILITIES, BUT GIVING A SUGGESTED HDG FOR A GIVEN DISTANCE TO ENSURE SEP COULD HAVE AVOIDED THE WHOLE SITUATION. IF THE SMA HAD MAINTAINED 500' BELOW THE CEILING, WE WOULD HAVE HAD MORE TIME TO SEE AND AVOID.

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.