This paper mentions to a research and development of an airboat. The airboat is developed for rescues works from storms, floods in rainy season with bad weather conditions. A special feature in the design of the airboat is using a hybrid propulsion system, water propeller and air fan. With the advantage of using two propellers, the airboat can run on multi-terrain such as on water surface, reed areas, swamps, on muddy surfaces. With a special feature in the hybrid propulsion system, when the air boat runs on water surface, it uses the water propeller for creating propulsion. The water propeller is designed to be flexible. When in use, the water propeller is dropped into the water, when not in use, the water propeller is pulled up on the airboat with its moveable shaft. There is a hydraulic coupling between the propeller shaft and the main engine of the airboat for easily switch the operating mode between the water propeller and the air fan. In addition, the hydraulic coupling also makes it easy to release and retract the propeller into the water. When running on surfaces other than water, the airboat uses the air fan propulsion mode. The propulsive fan is a specialized fan with high rotation speed and large air flow volume. The propulsive fan is directly driven by an aeronautical engine.