It's the Aircraft Registration Application (form 8050-1) that has to be done in triplicate and you keep the pink copy in the aircraft until you receive the printed one from the FAA. The Bill of Sale (form 8050-2) is sent to the FAA for recording, but no copy is required to be kept in the plane. The FAA doesn't really care who owns the plane. They only require the plane to be registered.


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