Evaluation of an aerial quadcopter power-plant for underwater operation

This paper presents a preliminary feasibility study of using aerial, fixed-pitch propellers, underwater. Tests were performs in both air and in water using a test stand that was designed to study the efficiency of commercially available, counter-rotating, multirotor propellers. Experimental results showed that the propellers can operate ably underwater in terms of thrust to power ratio at low rotational speeds without significant cavitation. These results are currently being used to develop a novel Unmanned Aerial Vehicle (UAV) quadcopter that can fly in air and maneuver underwater. The use of only a single set of aerial rotors and motors for use in both air and underwater greatly reduces cost, weight, and complexity compared to other Aquatic Aerial-Underwater Vehicle concepts.