University Of Arkansas Professor Designs Autopilot System To Keep It In The Air At Night
By Mason Carr
Robert Saunders, University Of Arkansas electrical engineering instructor, will design an autopilot system for the first solar-powered airplane scheduled to fly around the world in 20 days and 20 nights, making it the first solar-powered plane to continue flying at night.
Robert Saunders teaches classes on electric circuits and is a laboratory instructor for Electronics I. He previously helped design an autopilot for the Virgin Atlantic GlobalFlyer, an engine-powered craft that flew around the world nonstop; which is why he said he was contacted for the project started by two Swiss pilots.
Bertrand Piccard is leading the project that will fly the plane, Solar Impulse, around the world scheduled for 2015. He was the co-pilot of the first balloon to fly around the world nonstop, and is a member of scientifically respected Piccard family.
The Solar Impulse runs entirely on solar power and is one of the lightest planes developed despite having a wingspan the size of a football field installed with solar panels that power batteries, which run the propellers. Its wings are designed for stability and the plane’s rudders turn it. It is designed to reach its highest possible altitudes during the day, storing extra energy from the sun in batteries, and glide to an “optimal” altitude at night, while the sun is down, Saunders said.
The plane’s solar-powered predecessor, designed much the same way, reached a maximum altitude of about 28,000 feet.
The plane travels about 35 mph and will take several days to cross an ocean such as the Atlantic or Pacific, Saunders said.
Solar Impulse’s operational differences from other aircraft make the autopilot system an important piece for the safety of the human pilot.
“Because of the operation of the airplane, the pilot has to take (in) oxygen, at altitudes over 10,000 feet, and pretty much be alert at all times,” Saunders said. “When he goes over water, he needs some rest periods.”
The pilot is not allowed to rest more than 20 minutes at a time — because if the wings bank while he is asleep, it could set the plane drastically off course — making Saunders’ contribution that much more important.
