The Zephyr, a solar powered plane, flew for 82 hours 37 minutes, exceeding the current official world record for unmanned flight which stands at 30 hours 24 minutes set by Global Hawk in 2001 and Zephyr's previous longest flight of 54 hours achieved last year. The 3.5 day flight took place at Yuma Proving Grounds last month but was just announced. Keeping a solar powered plane in the air for 3 nights is no small feat.
Although touted as eventually being used for research purposes such as earth observation, the initial and primary uses will be military. The plane is jointly funded by the UK Ministry of Defence in partnership with the US Department of Defense (DoD).
The plane's builder, British defense contractor Qinetiq said, "Launched by hand, Zephyr is an ultra-lightweight carbon-fibre aircraft. By day it flies on solar power generated by amorphous silicon solar arrays no thicker than sheets of paper that cover the aircraft's wings. By night it is powered by rechargeable lithium-sulphur batteries, supplied by SION Power Inc, which are recharged during the day using solar power."
The flight trial at Yuma took place between July 28 and 31 with temperatures up to 113°F. Zephyr was flown on autopilot and via satellite communications to a maximum altitude of more than 60,000ft.