The Scaled Composites Model 281 Proteus is a tandem-wing high-endurance aircraft designed by Burt Rutan to investigate the use of aircraft as high altitude telecommunications relays. The Proteus is actually a multi-mission vehicle able to carry various payloads on a ventral pylon. An extremely efficient design the Proteus can orbit a point at over 65 000 feet (19 800 m) for more than 18 hours. It is currently owned by Northrop Grumman.
Made by Scaled Composites.