Does expiration of registration affect an aircraft's airworthiness certificate?
Because an aircraft with an expired registration is not registered, its airworthiness certification would be considered ineffective. Without registration the aircraft is not authorized for flight. Once registration is restored, the airworthiness certificate not having been surrendered, revoked or terminated would become effective again provided the aircraft is otherwise compliant with maintenance, inspections, and any other requirements for an effective airworthiness. If you have further questions please contact an airworthiness inspector through your nearest Flight Standards District Office.