Narrative:

The problem arose when the conflicting aircraft entered on a right base while I was on final from an ILS practice approach during VMC. There was another aircraft behind me on the ILS. The C210 on base called in sight and thought it was me, so he never had me in sight. I could not make any calls when 3 and 4 mi out because the C210 was talking to unicom about something other than flying at hand, so I couldn't talk with him. I noticed him right on top of me about 200 ft and immediately turned right and dove away. I noticed him right when he stopped talking to unicom and announced short final runway 2. 2 aircraft on final were contributing factors while the C210 was blocking the frequency talking of other matters than the ones at hand.

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Original NASA ASRS Text

Title: NMAC BTWN A PIPER PA28-161 ON A 2 MI FINAL OF A PRACTICE ILS APCH TO A NON CTLED ARPT AND A C210 TURNING ON FINAL FROM A R BASE LEG. THE INSTRUCTOR PLT IN THE PIPER FIRST OBSERVED THE CESSNA WHEN IT WAS APPROX 200 FT OVER HIS ACFT AND IMMEDIATELY TOOK EVASIVE ACTION.

Narrative: THE PROB AROSE WHEN THE CONFLICTING ACFT ENTERED ON A R BASE WHILE I WAS ON FINAL FROM AN ILS PRACTICE APCH DURING VMC. THERE WAS ANOTHER ACFT BEHIND ME ON THE ILS. THE C210 ON BASE CALLED IN SIGHT AND THOUGHT IT WAS ME, SO HE NEVER HAD ME IN SIGHT. I COULD NOT MAKE ANY CALLS WHEN 3 AND 4 MI OUT BECAUSE THE C210 WAS TALKING TO UNICOM ABOUT SOMETHING OTHER THAN FLYING AT HAND, SO I COULDN'T TALK WITH HIM. I NOTICED HIM RIGHT ON TOP OF ME ABOUT 200 FT AND IMMEDIATELY TURNED R AND DOVE AWAY. I NOTICED HIM RIGHT WHEN HE STOPPED TALKING TO UNICOM AND ANNOUNCED SHORT FINAL RWY 2. 2 ACFT ON FINAL WERE CONTRIBUTING FACTORS WHILE THE C210 WAS BLOCKING THE FREQ TALKING OF OTHER MATTERS THAN THE ONES AT HAND.

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.