BASAs between the US and partner countries (such as the EU, Canada, and Brazil) allow the FAA to accept airworthiness findings from the partner's civil aviation authority, reducing duplicative certification testing. However, the importer must still obtain an FAA airworthiness certificate before the aircraft can be registered and operated in the US.

Large civil aircraft have been the subject of long-running WTO disputes between the US and the EU. Retaliatory tariff authorizations have been granted to both sides at various points, and the status of any applied measures can change with negotiated suspensions or settlements. Importers should verify current tariff treatment with a licensed customs broker before finalizing purchase terms.