Narrative:

I called on [airport] frequency from five miles south that I was overflying ZZZ from south to north at 1;800 feet. I called again when directly over the field. At two miles north of the field an aircraft based at ZZZ overflew me at 200 feet and approximately 20 feet of horizontal separation; from my 12:00 position; each off the other's right wing. Immediately after the near miss; the [aircraft] called on the ZZZ frequency that he was two miles north at 2;000 feet and entering the pattern. I flew for another 15 minutes; [and] then returned to land.when on the ground I approached the pilot and stated I was concerned about the near miss. He stated; 'yes; I noticed that!' it is my impression it would have been appropriate for the [aircraft] to get on the frequency and call his position and intentions from more than 2 miles out. It was very busy at ZZZ at the time--there were three aircraft on downwind when the [aircraft] entered the pattern; such that one of the aircraft felt compelled to ask where the [aircraft] was.

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Original NASA ASRS Text

Title: The reporter; while transiting the airspace of a busy airport; describes a near miss within 200 feet of another aircraft in the landing pattern.

Narrative: I called on [airport] frequency from five miles south that I was overflying ZZZ from south to north at 1;800 feet. I called again when directly over the field. At two miles north of the field an aircraft based at ZZZ overflew me at 200 feet and approximately 20 feet of horizontal separation; from my 12:00 position; each off the other's right wing. Immediately after the near miss; the [aircraft] called on the ZZZ frequency that he was two miles north at 2;000 feet and entering the pattern. I flew for another 15 minutes; [and] then returned to land.When on the ground I approached the pilot and stated I was concerned about the near miss. He stated; 'Yes; I noticed that!' It is my impression it would have been appropriate for the [aircraft] to get on the frequency and call his position and intentions from more than 2 miles out. It was very busy at ZZZ at the time--there were three aircraft on downwind when the [aircraft] entered the pattern; such that one of the aircraft felt compelled to ask where the [aircraft] was.

Data retrieved from NASA's ASRS site 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.