Zephyr, the solar-powered plane that has been in the air for two weeks, it to come down to earth on Friday.
Zephyr was launched on July 9 and flew above the US Army’s Yuma Proving Ground in Arizona.
The unmanned, zero-emissions aircraft has been developed by QinetiQ as a cost effective alternative to traditional aircraft and satellites.
The Zephyr is transported in a standard road container and once launched can remain at a high altitude for weeks as it does not need to return to for re-fuelling or servicing.
For the trial in Yuma, Zephyr is carrying a communications payload configured to meet the needs of the UK Ministry of Defence.
As well as defence and security operations, commercial uses include environmental research; monitoring crops and pollution; providing tactical intelligence over disaster zones or forest fires; and delivering mobile communications capabilities in remote areas.
The aircraft flies by day on power delivered by amorphous silicon solar arrays which cover its wings and are no thicker than sheets of paper. The arrays also recharge lithium-sulphur batteries which power the aircraft by night.