• Bilateral agreements and arrangements allow the airworthiness certification of civil aeronautical products to be shared between two countries.

    A Bilateral Aviation Safety Agreement (BASA), Memorandum of Understanding (MoU) or Working Arrangement (WA) and their associated implementing procedures provide for technical cooperation between national civil aviation authorities. They help reduce duplication of activity and aim for mutual acceptance of certificates. 

    In addition to airworthiness certification, BASAs, MoUs and WAs provide for bilateral cooperation across other areas of aviation, including maintenance, flight operations, and environmental certification.

    For aircraft certification and maintenance, additional implementation procedures will cover specific issues such as design approval, production acceptance, export airworthiness approval, post-design approval activities, technical cooperation and maintenance.