the airfoil section and twist is not a problem, but the hub and join blend is
Always work from lines first. They are the skeleton of the model and serve as a back up if a shape goes side ways on you. From there the simpliest way would be to use 3 or 4 curves for lofts. As for a hub I imagine a revolve would be the easiest and then just be sure find the intersection between your lofted blades and the hub.