What’s more, the parts are interchangeable and can be swapped out during flight. This is the first entry in a contest Darpa is having for extreme-endurance planes. The commercial and civilian spinoffs from this contest could be significant.
It could have civilian applications: Langford imagines it as an atmospheric buoy, monitoring storm development, climate change or the health of the ozone layer. Either way, he says, it would demonstrate the potential of solar power and serve as a testbed for green aircraft technology. “If we can build an airplane that can stay up for five years with nothing but sunlight,” he says, “what else can we do?”