Seems like you could just convert to sub-d and not have to worry about converting the normals? Thats what I do.
Anyways, whats a good way to model a prop? I too am currently building a model of a radio controlled model Yak-54 and cannot get the prop to look good.
"Please excuse the crudity of this model, I didn’t have time to build it to scale or to paint it"
:: Dr. Emmett Brown