Formatting USB Drives for Avidyne Avionics on a Mac

Somehow, I never seem to get this right.

How to format to FAT16 on a Mac

The Avidyne EX5000 MFD requires a USB stick to be less than 2GB, and must be formatted to FAT16.

Use diskutil from a terminal, because Disk Utility won't actually do it.

# /dev/disk2 is the drive
# "USB" is the new name
diskutil partitionDisk /dev/disk2 MBRFormat "MS-DOS FAT16" "USB" 1000M

Updating navdata on the IFD550, IFD440 series

Pull circuit breakers to turn off all avionics except for the one you are updating.

I've only had success by going one at a time, so seperate the navdata and obstacles and upload them to each IFD individually. (Yes, it takes time).