Zephyr solar plane flies 7 days non-stop

The non-stop operation through day and night meant that the plane has now gone 4 times longer than the official mark recognised by the world air sports federation.

The plane has been developed by the defence and research company Qinetiq, and took off from the US army base in Arizona, where it is still in the air.

Their solar cells drive propellers during the day and top up their batteries to maintain the craft through the dark hours of night. An autopilot keeps them circling over the same spot.

The latest version of Zephyr is now 50% bigger than its predecessors.

The updated vehicle has a wingspan of 22.5m, and features a new wingtip and tail design that dramatically improve aero performance.

The previous world record for such a aircraft is just 30hours 24minutes set by the US robot Global Hawk.

The Zephyr flight is the second event of note this year in solar-powered aviation. Earlier this month, Andre Borschberg became the first person to pilot a manned solar plane through the night.

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