Eric Raymond has been designing, building and flying solar-powered airplanes for almost 30 years. Recently, his company, Solar Flight, released details for Sunstar, a new high altitude, solar powered, unmanned aircraft capable of staying aloft for months at a time.
His fourth solar aero design, Sunstar is intended to be an unmanned telecommunications platform that takes advantage of sailplane aerodynamics to maintain low power, high altitude flight. “What we are designing is known as an atmospheric satellite, which operates and performs many of the functions as a satellite would do in space, but does it in the atmosphere,” explained Raymond. “Uplink and downlink speeds will be far better than a satellite, due to the shorter distance.” In addition, it can provide service to a larger ground area than land-based towers.
The Sunstar solar plane features a three motor configuration. The front-mounted motors and props are optimized for take off and climb, and low altitude flying. When the aircraft reaches its target altitude, the front motors are disabled and the props folded back out of the airstream. Then a centrally mounted single pusher motor and large diameter propeller take over for the low power cruise.
Solar powered planes have gathered momentum in recent years, what with trans-continental trips by the likes of the Solar Impulse and Sunseeker airplane teams. Other groups have built boats powered by nothing but the sun to showcase the potential for solar power in the transportation world.
The designers have taken a modular approach to Sunstar’s design with an interchangeable central pod for instruments or pressurized pilot cabin. Sections of the wings can also be added or removed according to the needs of the mission. As well as mounting cells on the upper surfaces, the sides of the aircraft are also designed to harvest rays from low sun angles. A proprietary lamination on a new type of solar cell ensures a smooth outer skin.
The beauty of the Sunstar is that it will be far less expensive to put in position than a satellite, offers greater range than a normal broadcast tower and allows faster transmission times to and from the Earth. With benefits like that, its commercial possibilities should be enormous, Expect the first Sunstar solar plane to be ready for flight in 2 years time.