Narrative:

[I was] returning to ttd en route at 2;500 MSL 4 NM north of uao. [I] started a descent to avoid class C pdx airspace when a plane called that said they were 5 miles east of uao. While passing through 2;250 MSL in a descent spotted an aircraft at our 11 o'clock turning to the left. I took the controls and immediately started a climb avoiding the aircraft by a few hundred feet at most. I suspect the aircraft that I avoided was the same aircraft that reported to the east of uao. If [that] was the aircraft that reported to the east he was not in the vicinity of where he believed he was and his position call was pointless since he had no idea where he was. Giving no help to other aircraft that were in that area also in the proper maneuver to avoid another airplane head on he failed to execute the proper technique since he was turning left and not to the right.

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Original NASA ASRS Text

Title: C172 instructor pilot and trainee reported NMAC with another small aircraft in the vicinity of UAO. Reporter stated the other aircraft did not follow proper procedures.

Narrative: [I was] returning to TTD en route at 2;500 MSL 4 NM north of UAO. [I] started a descent to avoid Class C PDX airspace when a plane called that said they were 5 miles east of UAO. While passing through 2;250 MSL in a descent spotted an aircraft at our 11 o'clock turning to the left. I took the controls and immediately started a climb avoiding the aircraft by a few hundred feet at most. I suspect the aircraft that I avoided was the same aircraft that reported to the east of UAO. If [that] was the aircraft that reported to the east he was not in the vicinity of where he believed he was and his position call was pointless since he had no idea where he was. Giving no help to other aircraft that were in that area also in the proper maneuver to avoid another airplane head on he failed to execute the proper technique since he was turning left and not to the right.

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.