If archaeopteryx lived at a beach, and if there was a reliable sea breeze, it would not need to flap to fly. Beaches are excellent soaring locations for hang gliders, many renowned for the # of days per year that they are soarable (some over 2/3).
This sounds plausible, but is it possible with a gap between each short, rounded wing and body?
Some sort of land sail wings? I am not aware of any terrestrial animal that uses wind power to get around like people do in land sailing races out on dry lakebeds in the desert, or kite surfers with skateboards on land.
Wouldn't that require a vertical sail instead of horizontal wings?
Perhaps a variant of WAIR, where the wings just helped it run up a hill/dune faster with a tailwind, and maintain its balance when it runs down a hill/dune? It could be useful at some coastal dunes I suppose.
This runs into the same problems as WAIR in general: it requires a complex wingstroke that's unlikely to evolve from scratch, and that wingstroke apparently requires a large supracoracoideus muscle that wasn't there. WAIR further requires the ability to lift the wings above the body, which Archie and even *Confuciusornis* now appear to have lacked.