Solar powered aircraft take off

Within the next few weeks, a team of UK engineers hopes to launch an unmanned aircraft that could fly continuously for several months at altitudes of up to 65,000ft.

Powered by nothing more than the sun, the so-called Zephyr unmanned aerial vehicle (UAV) has been developed by engineers at Qinetiq who believe that such vehicles have huge potential across a range of scientific, military and civil applications.

The project also promises to reinvigorate the world of solar flight — an engineering dream that received what looked like a killer blow in 2003 when NASA’s much-lauded Helios solar plane met a watery end in the Pacific Ocean.

Now, thanks to advances in lightweight, high-strength composite materials, new developments in batteries and solar arrays and a fundamental rethink over the likely applications of solar aircraft, renewably powered UAVs may be about to enjoy their day in the sun.

Zephyr has its origins in an ill-fated attempt to set a high-altitude ballooning record in 2002. A tear in the balloon led to it being abandoned, but not before Qinetiq had developed a small, solar-powered aircraft to fly on a tether around the balloon’s gondola and film the record attempt.