MEDISONSHIP 4 sailed from Cairns to Meresu in December 2016 to join the fleet. MEDISONSHIP 4 represents the expansion of operations and the ability to service many more villages.

9.98mtr power catamaran with a 4mtr beam and a 0.9mtr draft. Built in Queensland in 2000 it is of solid fiberglass construction and powered by twin Niesen diesels, each producing 95hp. With a cruising speed of 8 knots, it uses 11 litres per hour for both motors. Includes accommodation for 7 people, a galley, toilet and shower, and refrigeration all powered by solar energy.