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Garmin 2018 charts navaid display issue
If you're using 2018 charts on your Garmin plotter and have set the navaids to show in the NOAA style, red buoys may be obscured.
Illustrated details here: https://www8.garmin.com/marine/notices/obscured_navigation_buoys.pdf
Credit to Garmin for notifying customers, and another reason to take extra care with any vector charts.
There's an interesting nuance here that was surprising to me. I would have figured that the actual rendering of what's on screen would be controlled by the MFD and its firmware. But something changed in the data contained in the charts to affect how they're displayed. That's counter to what I would have expected. It also makes me wonder if this is an issue of underlying chart data and whether any other manufacturers might be impacted. I suspect not, but it's possible this was caused by data Garmin ingests to build the chart bundle.
Agreed, kudos to Garmin for calling it out, though it's also interesting to note how long it's been an issue.