@Ailantd If it's about Dune-like ornithpoters: A piece of headcanon I have for those (contradicted by the recent movie, though) is that the reason for the preference for them over airplanes we'd find more typical is that you can make bending wings without any bearings (which would be hard to keep well lubricated and free of abrasive particles on Arrakis) in the form of some kind of a compliant mechanism.