While seeming to defy the basic physics of how propellers work, this conceptual render by Enki Marine indicates the internal blade structure that could be used to lighten the weight and reduce material cost in 3D printed maritime propellers. It's part of the D.E.E.P project—short for Digitally Enabled Efficient Propeller—to build the world’s first 3D printed, digitally monitored ship propeller that can track its own performance at sea. The project will test multiple AM processes against traditional casting to establish an AM classification in the maritime sector.