Solar-powered plane sets endurance record

FARNBOROUGH, England, July 17 (UPI) -- An unmanned solar-powered plane has set a record by remaining aloft for seven straight days, flying day and night, its designers say.

The "Zephyr" drone, developed by British defense technology company QinetiQ in Farnborough, England, took off from the U.S. Army's Yuma Proving Ground in Arizona July 9, CNN reported.

It was still flying at the weekend, and its designers say they hope it can remain airborne for another seven days, the U.S. news network said.

"It's extremely exciting," Zephyr program director Jon Saltmarsh said. "What we now have is an eternal plane. It has the same amount of fuel at the start of one day as it does at the start of another."

The Zephyr project was conceived in 2001 and funded by the United Kingdom's Ministry of Defense.

Saltmarsh says the aircraft demonstrates genuine military utility.

"It has the persistence to stay up there for long periods of time and it carries payloads that are doing things that the military will find useful," he said.

The Zephyr weighs just 117 pounds, has a wingspan of 74 feet and a wing area of about 323 square feet.

The top side of the wing is covered in solar panels thinner than a sheet of paper, CNN reported.