Who doesn’t want to fly like a bird in open air, with nothing but wings and a jet on your back? A few—like Swiss pilot Yves Rossy (see video below), whose self-designed rigid wing comes complete with jet engines—have succeeded, at least after a plane gets them up to the proper altitude. Now German researchers at ESG Elektroniksystem and Drager Aerospace are working on the jet-pack fantasy with the military in mind. They are developing a high-tech rigid wing with jet pack, the Gryphon, for the ultimate sneak attack: paratroopers with the maneuverability of a fighter plane.