Narrative:

I was VFR at 11;500 feet; west of cvg; not communicating with cincinnati approach; but monitoring their frequency. I saw a passenger jet approaching from my 10 o'clock; approximately 6 miles; 11;000 feet. This was confirmed by ads-B TCAS; which showed the other aircraft was descending. I maintained visual separation; no action necessary. I then heard approach ask the other aircraft if he had a visual on traffic '12 o'clock; indicating 11;600 feet.' which would have been my position relative to his aircraft. I could hear no responses from the other aircraft; but approach continued to ask if he had a visual on traffic; even after the jet passed my position. The jet passed approximately 500 feet below my aircraft.because of the time of day and aircraft positions; the sun was likely obscuring my aircraft from view; contributing to the other pilot's inability to get a visual on traffic.flying with VFR flight following or on an IFR flight plan would have opened communications between myself and cincinnati; which would have allowed a confirmation of my position to approach; and vectoring traffic for further separation.

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Original NASA ASRS Text

Title: C210 pilot reported an air carrier aircraft passed about 500 feet below his aircraft in the vicinity of CVG airport.

Narrative: I was VFR at 11;500 feet; west of CVG; not communicating with Cincinnati approach; but monitoring their frequency. I saw a passenger jet approaching from my 10 o'clock; approximately 6 miles; 11;000 feet. This was confirmed by ADS-B TCAS; which showed the other aircraft was descending. I maintained visual separation; no action necessary. I then heard approach ask the other aircraft if he had a visual on traffic '12 o'clock; indicating 11;600 feet.' Which would have been my position relative to his aircraft. I could hear no responses from the other aircraft; but approach continued to ask if he had a visual on traffic; even after the jet passed my position. The jet passed approximately 500 feet below my aircraft.Because of the time of day and aircraft positions; the sun was likely obscuring my aircraft from view; contributing to the other pilot's inability to get a visual on traffic.Flying with VFR flight following or on an IFR flight plan would have opened communications between myself and Cincinnati; which would have allowed a confirmation of my position to approach; and vectoring traffic for further separation.

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.