Narrative:

I was on short final at a CTAF airport in a C182 at approximately 300 AGL in class G airspace. I called my positions during the left traffic pattern; but I was inadvertently using the incorrect CTAF frequency. There was another aircraft in the pattern. Thus; the other aircraft in the left traffic pattern did not hear me and he did not know I was flying in the same traffic pattern with him. While I was on short final at approximately 250-300 feet above the ground; the other aircraft; which was flying a tighter pattern than me; turned onto left base above me in preparation for turning final at the same time I was on final. I did not see the other aircraft above me and never knew he was attempting to turn to final around the same time as me. The other aircraft saw me below him and did not turn onto final until after I landed. The pilot of the other aircraft informed me that he did not know I was there until seeing me on final below him and he believed that his pattern was a tighter traffic pattern than my traffic pattern because he was flying a smaller light sport aircraft; while I was flying a C182. I then realized that I was using XXX.8 as CTAF; instead of the correct frequency of XXX.9. The other aircraft did not need to take evasive action and he informed me that it was not 'that close;' but we discussed the situation and I thanked him for seeing me below him; so that the situation did not become any closer. I fly a high-wing cessna and his location above me in the pattern was obscured by my high-wing.

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Original NASA ASRS Text

Title: A C182 pilot in a CTAF landing pattern used the incorrect CTAF frequency for the proper position reports; but a Light Sport Aircraft pilot aborted his landing during a near miss after seeing the C182 ahead and below.

Narrative: I was on short final at a CTAF airport in a C182 at approximately 300 AGL in Class G airspace. I called my positions during the left traffic pattern; but I was inadvertently using the incorrect CTAF frequency. There was another aircraft in the pattern. Thus; the other aircraft in the left traffic pattern did not hear me and he did not know I was flying in the same traffic pattern with him. While I was on short final at approximately 250-300 feet above the ground; the other aircraft; which was flying a tighter pattern than me; turned onto left base above me in preparation for turning final at the same time I was on final. I did not see the other aircraft above me and never knew he was attempting to turn to final around the same time as me. The other aircraft saw me below him and did not turn onto final until after I landed. The pilot of the other aircraft informed me that he did not know I was there until seeing me on final below him and he believed that his pattern was a tighter traffic pattern than my traffic pattern because he was flying a smaller Light Sport aircraft; while I was flying a C182. I then realized that I was using XXX.8 as CTAF; instead of the correct frequency of XXX.9. The other aircraft did not need to take evasive action and he informed me that it was not 'that close;' but we discussed the situation and I thanked him for seeing me below him; so that the situation did not become any closer. I fly a high-wing Cessna and his location above me in the pattern was obscured by my high-wing.

Data retrieved from NASA's ASRS site as of July 2013 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.