Home2009 Treaties and Agreements ...Australia (09-417.1) – Memorandum of Understanding Concerning Cooperation in the P-8A Poseidon Spiral 1 Development Program hide Australia (09-417.1) – Memorandum of Understanding Concerning Cooperation in the P-8A Poseidon Spiral 1 Development Program TIAS Office of Treaty Affairs April 17, 2009 Defense: Cooperation Memorandum of understanding signed at Washington and Canberra April 3 and 17, 2009; entered into force April 17, 2009. With annexes. Download attachment [2 MB] Tags Australia Defense Treaties