Narrative:

On left 45 degrees entry for the left downwind runway 5 at deland municipal-sidney H taylor field when an unknown aircraft maneuvering within the proximity of the airport came within 500 feet off my left wing. I attempted to execute evasive maneuvering without losing sight of the aircraft by turning right; but the unknown aircraft continued to turn towards me and decreased separation. Separation decreased to about 400-500 feet until the other aircraft executed a turn northbound and climbed away from me.

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Original NASA ASRS Text

Title: GA pilot reported while downwind; they almost had a NMAC while trying to avoid an unknown aircraft.

Narrative: On left 45 degrees entry for the left downwind runway 5 at Deland Municipal-Sidney H Taylor Field when an unknown aircraft maneuvering within the proximity of the airport came within 500 feet off my left wing. I attempted to execute evasive maneuvering without losing sight of the aircraft by turning right; but the unknown aircraft continued to turn towards me and decreased separation. Separation decreased to about 400-500 feet until the other aircraft executed a turn northbound and climbed away from me.

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.