Narrative:

ATC suggested visual xy for landing. The traffic in pattern landing both directions doing touch and go. Tower was closed advised by ATC. Told to change to advisory by ATC on short final. Shifted to unicom 123.0 and announced with no response and nothing heard. Continued to announce with no response. At touchdown an aircraft flew over the top of me at 300 feet opposite direction. I saw him as I was landing and determined the safest course was to continue with landing. He was climbing out at that time. After stop I learned from line staff that CTAF was tower freq when tower was. It would have assisted me if ATC had given me this frequency. I got the unicom from garmin G1000 system. I will have to check if there is a designator in the system to indicate what freq is CTAF. I checked the VFR chart this [morning] and it described CTAF as tower freq.

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Original NASA ASRS Text

Title: The pilot of a C208 reported a near-mid-air-collision during a night approach after the tower was closed when the Unicom frequency was used for self-announcements rather than the CTAF frequency.

Narrative: ATC suggested visual XY for landing. The traffic in pattern landing both directions doing touch and go. Tower was closed advised by ATC. Told to change to advisory by ATC on short final. Shifted to Unicom 123.0 and announced with no response and nothing heard. Continued to announce with no response. At touchdown an aircraft flew over the top of me at 300 feet opposite direction. I saw him as I was landing and determined the safest course was to continue with landing. He was climbing out at that time. After stop I learned from line staff that CTAF was tower freq when tower was. It would have assisted me if ATC had given me this frequency. I got the Unicom from Garmin G1000 system. I will have to check if there is a designator in the system to indicate what freq is CTAF. I checked the VFR chart this [morning] and it described CTAF as tower freq.

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.