UAV flies through two nights

[zik]

From New Scientist:

"For the first time a solar-powered plane has flown through two consecutive nights, UK defence research company QinetiQ claims. In a secretive weekend mission, their craft Zephyr took off from a US military base in New Mexico and landed 54 hours later.

"The solar craft seems to have taken the next hop towards everlasting flight".

http://www.newscientist.com/blog/technology/2007/09/solar-flyer-en-route-to-everlasting.html

There's some video there too.

[AnthonyRC]

From New Scientist:

"For the first time a solar-powered plane has flown through two consecutive nights, UK defence research company QinetiQ claims. In a secretive weekend mission, their craft Zephyr took off from a US military base in New Mexico and landed 54 hours later.

"The solar craft seems to have taken the next hop towards everlasting flight".

http://www.newscientist.com/blog/technology/2007/09/solar-flyer-en-route-to-everlasting.html

There's some video there too.
Looks like AC Propulsion beat them too it.. by 2 years :)http://www.acpropulsion.com/solong/48_hour_flight.htm

[vector_vortex]

Apparently the Zephyr didn't need thermals to keep it aloft

[Jack Crossfire]

Amazing how much smaller and simpler the technology has become since Helios. Wonder if the Zephyr had to destroy its batteries to reach that goal.

[macboffin]

Here's a picture of the Aerovironment "Helios" taking off in 2003.

[rchant]

BBC news website has the most info;

http://news.bbc.co.uk/1/hi/sci/tech/6916309.stm

says that;-
"On the first flight, the aircraft, which has a wingspan of 18m (59ft), flew for more than two days before it developed a fault. The second, shorter flight was curtailed when thunderstorms threatened the propeller-driven plane."

Also;-
"A craft called SoLong, developed by US firm AC propulsion, flew for 48 hours in 2005. However, unlike Zephyr, the craft was not under constant power for the duration of the flight. Instead, it occasionally had to glide or soar."

SoLong was also quite small (5 metres or so) and was flown at comparitivly low altitude, which requires considerably less power.

i have also read elsewhere about Zephyr carring an optical payload, but understansably there is not much info about that.

Rich C.

[rchant]

Wonder if the Zephyr had to destroy its batteries to reach that goal.

the same batteries were used on the second flight.

Rich C.

[Magician]

Wonder if the Zephyr had to destroy its batteries to reach that goal.

Doesn't sound like it based on Rich's info. They are using a new battery chemistry though. They are running Lithium-Sulfur cells from Sion Power Corp (http://www.sionpower.com/) . This new chemistry shows great promise but the cells are not in full production yet and are currently very expensive since they are still made in a lab environment.

Chris

[Jack Crossfire]

Based on their 2004 claim, they could store 6.75Ah in the same weight that a Li-Po stores 4Ah, but only for 60 cycles. No-one knows the battery's performance for sure. Some say 300 cycles. Some say 60 cycles. At least they would smell better when they exploded.

http://news.com.com/Power-saving+pitches+for+notebooks+at+IDF/2100-1005_3-6047480.html