This is Boeing's "Phantom Eye," a hydrogen-powered, unmanned spy plane that flies 65,000 feet above the ground and can fly for four days straight. Boeing hails it as the "first of its kind" — its looks alone set it apart for that honor.
By comparison, one of the world's finest spy planes, the now-retired SR-71 Blackbird, operated at 85,000 feet and was manned by two pilots, though could only stay out a handful of hours.
Right now, Boeing's "four days" is more a goal than it is a hard figure. Later this summer, the Phantom Eye will perform its first taxi and ground tests at a NASA airbase, and then it'll go for its first test flight sometime in 2011. That test flight won't be the big four day soirée yet, as it'll last somewhere between four to eight hours.
This announcement comes days after the Solar Impulse completed its first 24-hour test fight. It makes one wonder: is seemingly-better-positioned hydrogen power the future of air travel, or will solar power be able to muscle its way in?