wtf is sky-tribe-evtol?

Sky Tribe is an open source project to design and build a real, single seat aircraft that takes off and lands vertically like a small drone, and can also land on water and take off again. It uses electric power instead of a traditional engine, and is meant to fly under the American FAA's Part 103 ultralight rules, which do not require a pilot's license or aircraft registration for a version light enough to qualify. The whole design is shared publicly: the 3D CAD files, the full list of parts needed to build one, and the research and calculations behind every design choice. The aircraft flies using eight small motors arranged on four arms, one on top of the other at each arm, a layout the project chose because it can keep flying safely even if one motor fails, unlike a simpler four motor design. There are two versions built from the same basic frame. One is a heavier version meant to test the idea and prove it works, which needs a license to fly because it exceeds the ultralight weight limit. The other is a lighter version built to fit inside the ultralight weight rules so it can be flown without a license. The project is unusually honest about what does not yet work. Early power estimates for hovering turned out to be too optimistic once real world losses were accounted for. Flight time is short, around eleven to fifteen minutes for the heavier version and six to eight minutes for the lighter one. Top speed is limited by the physics of the rotors themselves, not by available power. The lighter version is currently a little over its legal weight limit and needs further design work to fix. Cost is also broken down openly, from about five thousand dollars just to test a single motor on a stand, up to around one hundred forty thousand dollars for the entire program including both aircraft and a backup fuel powered generator option. Before any person ever sits in the aircraft, the plan requires testing it unmanned and then with sandbags standing in for a pilot, across many flights, to prove it is safe first.