Solar Plane Breaks Endurance Record

calmond writes with this excellent snippet from CNET News: "QinetiQ Group PLC claimed Sunday that its propeller-driven aircraft called Zephyr flew for 83 hours and 37 minutes non stop, more than doubling the official world record set by Northrop Grumman's Global Hawk in 2001. The Zephyr is much different from the Global Hawk, which is about the size of a fighter and requires runway for taking off and landing. Zephyr, on the other hand, is an ultra-lightweight carbon-fiber aircraft that weighs less than 70lbs and is designed to launch by hand. The little aircraft flies on solar power generated by amorphous silicon arrays covering the aircraft's paper-thin wings. It is powered day and night by rechargeable lithium-sulfur batteries that are recharged during the day using solar power."

Comments

BBC report with video is better

[Herschel Cohen]

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

Lithium-Sulfur Batteries

[Gruff1002]

Sulfur is a relatively cheap material, so lithium-sulfur batteries have the potential to be less expensive than other battery types. With a lower starting cost to manufacturers, lithium-sulfur batteries could save consumers money. There is also a possible cost savings because lithium-sulfur batteries tend to provide much longer charges than lithium ion batteries. With double the lifetime or greater, you might be able to get by with a single lithium-sulfur battery for your laptop or rechargeable hand tool. Another reported advantage of lithium-sulfur batteries is their ability to work well in very cold weather. www.wisegeek.com

Re:...and this isn't a new one...

[jmpeax]

The "rule" they didn't follow was to have the relevant organisation in on the action. From the BBC:

[The record] remains "unofficial" because QinetiQ did not involve the FAI (Federation Aeronautique Internationale), the world air sports federation, which sanctions all record attempts.

I think it's fair to say that regardless of who officiates it, they have broken the record.

Re:The record is only for unmanned aircraft.

[icegreentea]

The record for longest manned flight is 64 days.

http://thelongestlistofthelongeststuffatthelongestdomainnameatlonglast.com/long219.html
http://news.bbc.co.uk/1/hi/special_report/1998/11/98/great_balloon_challenge/299568.stm

Cessna out of Nevada flew for 64 days, 22 hours, covering the equivalent of 6 circumferences of the earth. In flight refueling, and they dropped down to just above ground level to pick up supplies from a chase car.

What about the Condor UAV?

[Goldenhawk]

I think the claim to have beaten the Global Hawk by 2x is a bit misleading - it implies a doubling of existing capabilities. In fact, it only UNOFFICIALLY doubles an OFFICIAL record, which itself is not the longest flight recorded by any means. In 1989 a Boeing UAV named Condor flew over 58 hours, and had a design endurance of 80 hours. Okay, they never claimed it as an official record, but it was still a valid flight, just like this was.

Here's an interesting video:
http://video.aol.com/video-detail/boeing-condor-uav/4285692709

And some facts:
http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=7988

Granted, the Zephyr is theoretically limited only by the service life of its electrical components - it could stay up until something broke or wore out. But please, let's use real facts here.

Re:Fly forever!

[Thagg]

But it did come down, which means, some resource got drained... Which one? The batteries, which may have been only partially recharging during the day, is one possible explanation....

The first people to fly a solar-powered plane through the night, Tom Gage and his team at AC Propulsion, flew for 48 hours...and could have probably flown forever -- the resource that was drained was the on-ground pilots.

The plane was flown to use thermals as much as possible during the day, but it was tiring work.

Anyway, after two days, and with a battery charge higher than what they started at, they figured that they had made their point.

Re:The record is only for unmanned aircraft.

[arth1]

The record for longest manned flight is 64 days.
[chop]
Cessna out of Nevada flew for 64 days, 22 hours, covering the equivalent of 6 circumferences of the earth. In flight refueling, and they dropped down to just above ground level to pick up supplies from a chase car.

Valeri Polyakov did a 437 day flight, with a flight distance covering more than 7 thousand times the circumference of the earth.

Of course, his flight being disregarded isn't surprising, him not being an American.
Consider:

Eilmer of Malmesbury, who flew 220 yards in a glider in the 11th century
Lagari Celebi, who flew an unspecified distance with a rocket in 1633 (well documented!)
Henri Giffard, who flew 16 miles in a powered airship in 1852
George Cayley, who flew a mile in a controlled glider in 1853
John Stringfellow, who flew several dozen feet in a powered monoplane in 1868
Clement Adler, who flew 60 yards in a powered monoplane in 1890, and 320 yards in 1987
Richard Pearse, who flew over 1000 yards, including a controlled turn, in May 1903
Orville Wright, who flew 120 yards in a powered but wind-aided biplane in December 1903
Wilbur Wright, who flew 190 yards in a powered but wind-aided biplane in December 1903

Who gets honoured with having made the first flight? The Americans, of course! The "rules" have been rewritten several times after the fact to include the Wrights and exclude others.

So I guess that the rules for flight now specifically excludes orbital flights in order to disqualify MIR. Eppur si vola.