I'm not sure if you're referring to a prop with no twist or a prop with no pitch. The prop has to have at minimum an effectively positive pitch.
I think I mean a prop with no twist, a prop with no pitch would be---- a piece of wood :-) I'm not sure what I mean anymore, somewhere along the line some video suggested the vehicle can go DDWFTTW be cause the prop is tacking to the wind. This is not the video, but does give the general idea.