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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."
http://news.bbc.co.uk/2/hi/science/nature/7577493.stm
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
[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.
Amnesty International
Actually, it doesn't need to be daytime for it to operate, hence how it was able to stay airborne for 83 hours. It uses high capacity batteries to get through the night.
Amnesty International
According to the BBC article it carried a 2kg payload. That's enough for a decent observation and communications platform and this is only a prototype - they're talking about a much bigger version that could stay aloft for months.
Sion Power make the Lithium Sulfur batteries and they claim an energy density that's almost twice that of Lithium Ion. If that's true the power shouldn't be too much of a problem once the UAV's reached cruising altitude. It would be good to know some more about those batteries...
One of these days I'm moving to Theory - everything works there
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.
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.
--Brandon / Split Infinity Music
QinetiQ CIA link
QinetiQ, the British defence and security technology company that was spun out of the Ministry of Defenceâ(TM)s research laboratory, has appointed George Tenet, 53, former head of the CIA in America, a non-executive director. The company hopes to develop closer links with the US intelligence establishment.
"Speaking the Truth in times of universal deceit is a revolutionary act." -- George Orwell
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.
I love Mondays. On a Monday, anything is possible.
As explained in the BBC article, flying over one of the poles is not necessary to fly forever. This team is now working on a defense project codenamed Vulture to extend their design to be able to fly non-stop for 5 years on any spot on the Earth's surface. Although they don't mention why Zephyr couldn't fly more than 84 hours, presumably it was either because it wasn't able to recharge its batteries fast enough during daytime, or they voluntarily stopped the experiment after 84 hours. In any case it looks like their design is not far from being able to "fly forever".
Anyone who writes that the Global Hawk is the size of a fighter has never seen one in person. The damn thing is HUGE. The wingspan is even greater than that of a U-2. It's an awesome plane with some serious potential.
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.
Oooh, I can't let this statement go unchallenged!!!
I also believe the early reports of flying achievements are greatly skewed by American supporters of the Wright brothers, but I do believe that one should be accurate in attacking this. This list has several inaccuracies which need correcting!
There is no indication that Cayley's flights were controlled. Stringfellow flew models, not man-carrying machines. Richard Pearse's amazing achievements were never, unfortunately, properly documented, so the assertion above is a guess (though likely).
You have not mentioned Sir Hiram Maxim (1894), or Santos-Dumont. Nor Whitehead or Langley.
You have also missed out the critical point which this whole thread is about - that a particular record or achievement is invariably hedged round by the conditions it occurs under, and that it is qualified by. The Wrights claim for the 'first flight', depends on your accepting their qualifications. At the time they were arguing for legal patent control of flight, and so made some very precise distinctions. Their claim was that they were the first 'documented, heavier-than-air, man-carrying, controlled, powered flight, which had assistance leaving the ground, but landed safely.', which seems justifiable. But note that this does NOT mean 'the first flight'.
The American press has always trumpeted this as a breakthrough, but really it was part of an unbroken succession of human endeavor. My take on the critical steps are:
1783 - Montgolfier Bros/ Jacques Charles - first documented balloon flights
1790-1850 - Sir George Cayley - first aeronautical engineer, designed first stable heavier-than air glider, made first documented man-carrying, heavier-than-air glider.
1850-1860 - John Stringfellow - first documented heavier-than-air powered aircraft (model)
1890 - Clement Ader - first documented man-carrying, heavier-than-air powered hop
1891 - Otto Lilienthal - first documented man-carrying, heavier-than-air, controllable flight
1894 - Sir Hiram Maxim - first documented man-carrying, heavier-than-air powered flight
1901 Gustave Whitehead - first undocumented man-carrying, heavier-than-air powered flight
1903 William Pearce - first undocumented man-carrying, heavier-than-air powered controlled flight
1903 Wright Brothers - first documented man-carrying, heavier-than-air powered controlled flight (with take-off assistance)
1906 Santos-Dumont - first documented man-carrying, heavier-than-air powered controlled flight with no assistance
And that's just a few high points - there were many others in between!
The importance of the Wright Brothers (apart from their being American) was that they developed the first workable 3-axis mechanical control system. This was essential for the further development of aviation - body-weight shifting would not scale. Unfortunately, neither would the wing-warping which the Wrights developed. Mechanical flap controls of the kind used in Europe (and also by Pearce) were the way ahead. The Wrights tried to patent ALL methods of control, and successfully closed down American aviation development until the First World War.
For my money the most impressive pioneer was Cayley. He would certainly have had a full aircraft if the technology of the time had allowed it - as it was he predicted what was required with startling accuracy. His papers are still well worth reading for all engineers...
There's also a lot less latency when you don't have to go the extra few miles between syn and ack packets.
lol: You see no door there!