Solar Powered UAV Stays Aloft For Weeks On End
QinetiQ's solar powered Zephyr UAV.
60,000 feet above the Arizona desert, a UAV has been slowly circling the U.S. military’s Yuma Proving Grounds facility. Normally, that wouldn’t be that strange. But this UAV has been up there for an entire week, breaking previous drone flight records by orders of magnitude.
The UAV, manufactured by QinetiQ and named the Zephyr, has already doubled the previous record for longest flight time by a UAV. Additionally, since the Zephyr is also solar powered, it doesn’t need to land any time soon, and could conceivably stay aloft indefinitely .
“In theory, it can fly forever, and it's range is unlimited,” said John Saltmarsh, the program director for QinetiQ’s Zephyr project. “In practice, we’re only going for 2 weeks here, and staying in a 40 mile box.”
The secret to the Zephyr’s success lies in its construction. An ultra light carbon fiber frame cuts down on weight, paper-thin solar panels provide energy and lithium-sulfur batteries store energy for flying at night . Additionally, by soaring at such a high altitude, the Zephyr avoids powerful headwinds caused by the jet stream, Saltmarsh said.
In fact, the aircraft is so light that for take off, a half dozen people lift up the Zephyr and run into the wind, like a hang glider, until the plane catches an updraft.
The Zephyr cruises at around 40 knots (46 mph), and its camera or electronic payload can cover a 154 square mile (400 square km) area. With its nearly unlimited flight time, that means the Zephyr can fulfill the same communications or observation role as a spy satellite, but at a fraction of the cost.
This test in Arizona is more of a proof of concept than anything else, but QinetiQ could have Zephyr UAVs in theater, flying above Afghanistan , within a year, Saltmarsh said.