Narrative:

While departing from an uncontrolled airport (bwg) in a C172 without radios, I noticed a PA28 on a 5 mi right crosswind. The spacing looked adequate so I started to turn a left crosswind at 500 ft AGL. At this point I surmised the PA28 was going to enter on a left crosswind to follow any C172. When I started for my left downwind leg I still had not obtained tpa (traffic pattern altitude). When I looked up the PA28 had flown over the top of me at a 45 degree angle. A near miss of about 300 ft (see diagram). I would conclude the problem arose due to the pilot of the PA28 lack of knowledge to enter a pattern at an uncontrolled airport. I would also say that not having radios in the C172 contributed to their situation. I was told by another CFI in the pattern at the time that the FSS on the field advised the PA28 that I had no radios and I had just departed. The pilot in the PA28 acknowledged this and stated he had me in sight.

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Original NASA ASRS Text

Title: RPTING PLT OF C172 HAS NMAC WITH PA28 PLT ENTERING TFC PATTERN AT NON TWR ARPT IMPROPERLY.

Narrative: WHILE DEPARTING FROM AN UNCTLED ARPT (BWG) IN A C172 WITHOUT RADIOS, I NOTICED A PA28 ON A 5 MI R XWIND. THE SPACING LOOKED ADEQUATE SO I STARTED TO TURN A L XWIND AT 500 FT AGL. AT THIS POINT I SURMISED THE PA28 WAS GOING TO ENTER ON A L XWIND TO FOLLOW ANY C172. WHEN I STARTED FOR MY L DOWNWIND LEG I STILL HAD NOT OBTAINED TPA (TFC PATTERN ALT). WHEN I LOOKED UP THE PA28 HAD FLOWN OVER THE TOP OF ME AT A 45 DEG ANGLE. A NEAR MISS OF ABOUT 300 FT (SEE DIAGRAM). I WOULD CONCLUDE THE PROB AROSE DUE TO THE PLT OF THE PA28 LACK OF KNOWLEDGE TO ENTER A PATTERN AT AN UNCTLED ARPT. I WOULD ALSO SAY THAT NOT HAVING RADIOS IN THE C172 CONTRIBUTED TO THEIR SIT. I WAS TOLD BY ANOTHER CFI IN THE PATTERN AT THE TIME THAT THE FSS ON THE FIELD ADVISED THE PA28 THAT I HAD NO RADIOS AND I HAD JUST DEPARTED. THE PLT IN THE PA28 ACKNOWLEDGED THIS AND STATED HE HAD ME IN SIGHT.

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.