Seems to me that the US has some kind of new tech that they just don't want to share so they're going hard with this new disclosure movement. Probably something like an unmanned version of the AEREON 26 hybrid airship. Essentially half-blimp half-jet, its close to neutrally buoyant so it could "tumble" through the air like what we've seen in the tic-tac video released by the Navy.