Zephyr-6 uses solar power to fly for three days

A UK-built solar-powered plane has set an unofficial world endurance record for a flight by an unmanned aircraft.

The Zephyr-6, as it is known, stayed aloft for more than three days, running through the night on batteries it had recharged in sunlight.

The flight was a demonstration for the US military, which is looking for new types of technology to support its troops on the ground.

Craft like Zephyr might make ideal platforms for reconnaissance.

They could also be used to relay battlefield communications.

Chris Kelleher, from UK defence and research firm QinetiQ, said Unmanned Aerial Vehicles (UAVs) offer advantages over traditional aircraft and even satellites.

"The principal advantage is persistence - that you would be there all the time," he told BBC News. "A satellite goes over the same part of the Earth twice a day - and one of those is at night - so it's only really getting a snapshot of activity. Zephyr would be watching all day."

http://news.bbc.co.uk/2/hi/science/nature/7577493.stm

Son of Concord to offer commercial flights at 3400mph

The revolutionary plane called A2 will fly at a top speed of 3,400mph and should be able to carry 300 passengers. To reach Mach 3 the plane initially generates thrust through engines similar to those used in conventional jet aircraft. Beyond Mach 3, the super-heated air is pre-cooled before it enters the turbines, preventing the engines from melting. The plane has a minimal carbon footprint because it is fueled by liquid hydrogen, producing only water vapor and nitrous oxide as exhaust.

The A2 will cruise at an altitude of 100,000ft. A ticket from Europe to Australia is estimated to cost around $4000.