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If AutoFill Aircraft is enabled and imports an aircraft tail number that has not been previously entered into APDL, it will be added to the default type set in Settings/Settings > Aircraft. This allows you to configure your aircraft types in the format that you prefer (B737 vs. Boeing 737 vs. 737-800 etc.) while still using AutoFill Aircraft. If you fly multiple types of aircraft, the default should be set to "Undefined Types" so it will not assign an incorrect type to your tail number and can be manually set later. To change the type from "Undefined Types" to the appropriate type, see the guidance on how to Change the Aircraft Type Associated with a Tail Number.
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