“Supersonic is not—as of yet—actually here, despite the seductive geometry and messaging of the advertisement by United, which has signed on to buy 15 planes that have not yet been built (but have generated a fair amount of positive media attention in an otherwise disastrous year). Where it is, at least putatively, is propped up on a platform inside the headquarters of Boom Supersonic, a low-slung building adjacent to Centennial Airport in the suburbs of Denver, Colorado.”