Narrative:

Approached plattsmouth airport (pmv) from the west at 2;200 MSL with intention to practice landings with student. AWOS reported wind direction from 240; which slightly favored runway 16. Announced on CTAF (122.7) intention to enter left downwind to runway 16 by crossing runway at midfield. An unidentified voice came over CTAF stating 'active runway is 34.' I replied on CTAF 'winds favor 16.' I then saw aircraft Y holding at the approach end of runway 34. I announced on CTAF we would switch to runway 34. I instructed my student to continue across the airport and climb to 2;700. We turned south approximately one mile east of the runway and turned south. We turned back to the west and passed one mile south of the airport. We then heard the aircraft Y pilot report 'aircraft Y...departing the pattern to the south.' I immediately announced my position 'aircraft X...south of plattsmouth at 2;700 feet.' about 12 seconds later I spotted aircraft Y below our altitude on an intersecting course. At the same time aircraft Y pilot came on the radio and said 'aircraft X at plattsmouth; I'll fly under you.' I replied; 'I see you; aircraft Y; have a good flight.' he passed under and slightly behind us. To prevent a recurrence I would query the departing aircraft as to direction of flight and plan pattern entry accordingly. Had aircraft Y been showing a landing light; I would have seen him much sooner. A contributing factor to this occurrence was the wind direction being nearly perpendicular to the runway; making runway selection somewhat ambiguous.

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Original NASA ASRS Text

Title: GA instructor reported an NMAC near PMV.

Narrative: Approached Plattsmouth airport (PMV) from the west at 2;200 MSL with intention to practice landings with student. AWOS reported wind direction from 240; which slightly favored runway 16. Announced on CTAF (122.7) intention to enter left downwind to Runway 16 by crossing runway at midfield. An unidentified voice came over CTAF stating 'Active Runway is 34.' I replied on CTAF 'Winds favor 16.' I then saw Aircraft Y holding at the approach end of Runway 34. I announced on CTAF we would switch to Runway 34. I instructed my student to continue across the airport and climb to 2;700. We turned south approximately one mile east of the runway and turned south. We turned back to the west and passed one mile south of the airport. We then heard the Aircraft Y pilot report 'Aircraft Y...departing the pattern to the south.' I immediately announced my position 'Aircraft X...south of Plattsmouth at 2;700 feet.' About 12 seconds later I spotted Aircraft Y below our altitude on an intersecting course. At the same time Aircraft Y pilot came on the radio and said 'Aircraft X at Plattsmouth; I'll fly under you.' I replied; 'I see you; Aircraft Y; have a good flight.' He passed under and slightly behind us. To prevent a recurrence I would query the departing aircraft as to direction of flight and plan pattern entry accordingly. Had Aircraft Y been showing a landing light; I would have seen him much sooner. A contributing factor to this occurrence was the wind direction being nearly perpendicular to the runway; making runway selection somewhat ambiguous.

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.