https://www.eaa.org/eaa/aviation-interests/ultralights/getting-started-in-ultralight-flying/about-faa-part-103-for-ultralights Even under these rules, it's kind of cool. If I had a homestead, this could be a hell of a way to ride the fences. Can't use it in "congested areas" meaning quick grocery trips are out of the question. No class D airspace means you are likely limited to 2500 ft, but then, why would you want to be higher in this?