Narrative:

I was on a flight from madison to appleton and had planned to fly a route well west of the oshkosh area to avoid the heavy traffic of incoming eaa flts. Near karkesan I spotted traffic ahead and while I was tracking the aircraft, another aircraft approached from the west and passed over me at about 100-150' above me. I have no idea if this aircraft was aware of my presence! I was pretty shook up and became disoriented. I am familiar with the area yet nothing looked familiar. I was so preoccupied with checking for other traffic and trying to verify my position that I inadvertently drifted to the west and was within 1 mi of the oshkosh traffic area when I finally established my position. (There are 2 towers on the west edge of the oshkosh airport traffic area.) at this point I was very nervous about my location and had to decide if I should fly west or confess my position to warn incoming traffic of my presence. I decided the only safe action would be to announce my position. Incoming traffic was on a 'monitor only' system. I was 1 mi west of the air traffic area but when I announced, I said '1 mi west of the airport'. By the time I realized what I had announced it was too late to correct it and I didn't want to interrupt the tower frequency again. Basically the flight would have been uneventful except for the incident over markesan. I was pretty shook up and made some errors getting myself back on course, then made an error announcing my position near oshkosh.

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Original NASA ASRS Text

Title: PRIVATE PLT ON SHORT CROSS COUNTRY NEAR OSH HAD NMAC THEN ENTERED ATA WHILE WATCHING FOR TRAFFIC.

Narrative: I WAS ON A FLT FROM MADISON TO APPLETON AND HAD PLANNED TO FLY A ROUTE WELL W OF THE OSHKOSH AREA TO AVOID THE HEAVY TFC OF INCOMING EAA FLTS. NEAR KARKESAN I SPOTTED TFC AHEAD AND WHILE I WAS TRACKING THE ACFT, ANOTHER ACFT APCHED FROM THE W AND PASSED OVER ME AT ABOUT 100-150' ABOVE ME. I HAVE NO IDEA IF THIS ACFT WAS AWARE OF MY PRESENCE! I WAS PRETTY SHOOK UP AND BECAME DISORIENTED. I AM FAMILIAR WITH THE AREA YET NOTHING LOOKED FAMILIAR. I WAS SO PREOCCUPIED WITH CHECKING FOR OTHER TFC AND TRYING TO VERIFY MY POSITION THAT I INADVERTENTLY DRIFTED TO THE W AND WAS WITHIN 1 MI OF THE OSHKOSH TFC AREA WHEN I FINALLY ESTABLISHED MY POSITION. (THERE ARE 2 TWRS ON THE W EDGE OF THE OSHKOSH ARPT TFC AREA.) AT THIS POINT I WAS VERY NERVOUS ABOUT MY LOCATION AND HAD TO DECIDE IF I SHOULD FLY W OR CONFESS MY POSITION TO WARN INCOMING TFC OF MY PRESENCE. I DECIDED THE ONLY SAFE ACTION WOULD BE TO ANNOUNCE MY POSITION. INCOMING TFC WAS ON A 'MONITOR ONLY' SYSTEM. I WAS 1 MI W OF THE ATA BUT WHEN I ANNOUNCED, I SAID '1 MI W OF THE ARPT'. BY THE TIME I REALIZED WHAT I HAD ANNOUNCED IT WAS TOO LATE TO CORRECT IT AND I DIDN'T WANT TO INTERRUPT THE TWR FREQ AGAIN. BASICALLY THE FLT WOULD HAVE BEEN UNEVENTFUL EXCEPT FOR THE INCIDENT OVER MARKESAN. I WAS PRETTY SHOOK UP AND MADE SOME ERRORS GETTING MYSELF BACK ON COURSE, THEN MADE AN ERROR ANNOUNCING MY POSITION NEAR OSHKOSH.

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.