China, Australia, New Zealand and the United States kicked off a three-day humanitarian aid tabletop exercise on Wednesday in Nanjing, Jiangsu province to further strengthen coordination and cooperation in joint rescue missions.

The exercise, dubbed Cooperation Spirit 2017, involved 28 naval and air force rescue personnel from the four countries. Their training scenarios involved joint search and rescue operations for fallen planes in the eastern Indian Ocean.

The exercise uses actual data, ranging from water temperature to wind patterns, to simulate the most realistic situation possible, said Chen Min, the head of the scenario director team.

It aims to improve efficiency in command, coordination, logistics and other key disaster relief protocols, he added.

More than 70 observers and representatives from the participating four countries, as well as from Canada, the Independent State of Papua New Guinea, and the International Committee of the Red Cross, attended the exercise’s opening ceremony.

China and Australia held the first Cooperation Spirit exercise in 2011 as an effort to increase non-combat military cooperation. It was later expanded to include New Zealand and the United States.