Narrative:

I was practicing RNAV approaches to gif's rwy 11 in VFR conditions. On the RNAV approach at 10 nm from the airport a cessna 172 flew over me and immediately behind me. I was watching my adsb in and the approach was clear. The aircraft 'popped up' onto the adsb in display approx 2 seconds before it passed 400 feet above and approx 50 feet aft. Adsb data was used to determine the 400 foot separation.

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Original NASA ASRS Text

Title: Pilot of a home built aircraft reported an NMAC with another light aircraft in the pattern at GIF airport.

Narrative: I was practicing RNAV approaches to GIF's Rwy 11 in VFR conditions. On the RNAV approach at 10 nm from the airport a Cessna 172 flew over me and immediately behind me. I was watching my ADSB in and the approach was clear. The aircraft 'popped up' onto the ADSB in display approx 2 seconds before it passed 400 feet above and approx 50 feet aft. ADSB data was used to determine the 400 foot 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.