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Solar Craft Flies Through Two Nights
An anonymous reader writes "A solar-powered, unmanned craft has flown for 54 hours — a record for both unmanned aerial vehicles and solar craft. None before has managed to store enough solar energy to fly through more than one night. There is also a video showing the 18m carbon fiber wing craft being launched."
This BBC article has good info.
It should not be a surprise that the Global Hawk record did not stand. Look at the two craft. If a global hawk hit the zephyr it probably wouldn't even notice.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
Sure if it could go 1000 mph, that would work fine. It might be tricky to break the sound barrier with a solar-powered craft though.
Sure, if it's fast enough. Solar powered aircraft tend to be driven by large, slow-turning propellers. Even commercial jet aircraft typically can't beat the Sun from the eastern US to the west, so I doubt we'll be seeing such a solar powered aircraft anytime soon.
"Open the pod by doors, Hal" > "I'm afraid I can't do that, Dave" sudo "Open the pod bay doors, Hal" > alright
From Wikipedia:
"Engouh Solar Energy (ESE) is a newly-discovered form of solar energy capable of lighting even the darkest parents' basement to the point where the average nerd can neither see his keyboard nor the inevitable typos he'll make on internet discussion boards."
it's good for learning things to be used in later vehicles that will accomplish, you know, stuff
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
I read it as "enough". Then again, I read this article earlier.
What the hell kind of spelling mistake is that? A typo?
Wind sure, but not weather. The thing cruised at 18,000 meters, solidly in the Stratosphere; not much up there but ozone. Even the wind wouldn't be that big a deal; the stratosphere is so called because it sits in layers (strata), and as long as you're not climbing or descending, your environment should stay pretty much the same.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
Obviously solar panels feed it to maintain energy stores; however since it must store this energy in a battery of some sort, is it required that the batteries be empty when launched? If not, what's to stop someone with a major pile of pre-charged solar-rechargeable batteries from tacking one solar panel on top & calling it a solar vehicle even if it could never fully charge those during use? Not accusing these folks of doing that but just curious about how they classify solar vehicles...
digital artist, 3D animator, web designer, and otherwise technological creative type....
I, for one, welcome our [can't think of a damn thing witty] overlords.
Robotic, solar powered flying overlords?
Seven puppies were harmed during the making of this post.
Depending on the time of year it wouldn't have to do that... you could have it do loops around the north or south pole at a much higher latitude and still get sunshine 24/7 (or damn near close) and not have to travel as fast as they would near the equator to keep up with the sun.
Yes, but then again vampires aren't exactly solar powered. Unless you count the motivation to avoid the Sun as a power source.
The higher the technology, the sharper that two-edged sword.
Can this thing seriously carry any cargo that is worthwhile?
Well if you're in the used battery business, this thing is a gold mine!
Seven puppies were harmed during the making of this post.
A series of halogen lights mounted along the wings are illuminated at night to power the solar array.
What the hell kind of spelling mistake is that? Come on editors, at least READ the edited summary...
Storing energy is the key. You might be able to store it in batteries like these people have done, or store it in your altitude and just let it glide down at night -- but that would require a really efficient plane. This looks to be a really efficient plane, but it's obviously not quite efficient enough to do that.
That would be cool if they'd try to fly it across the Atlantic -- it would be the first electric plane to do so, and the first solar powered plane to do so. TAM 5 took 39 hours to cross the Atlantic, and this plane was up longer than that -- but it's a lot slower too. TAM 5 averaged about 48 mph, and I'll bet this plane is less than half that.
During the day, it flys with the sun, to get a longer day. Then during the night, it flys in the opposite direction in order to achieve a shorter night.
God spoke to me.
There are some problems with that idea.
That would work only in the summer.
That would be handy only if you needed that aircraft over the polar region during the summer months.
Then you have the really big problem...
The solar panels are mounted on the wings... The sun at the poles never climbs very high in the sky so the panels would have to be mounted on the sides of the aircraft. That would limit your collecting area a lot and or produce a lot of drag.
So the idea while interesting at first glance really is far from practical.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Darn memes. Engouh already!
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Looked at your /. username lately?
"The best argument against democracy is a five minute chat with the average voter."
--Winston Churchill
In case you don't want to do the rough math, the Earth is a little less than 25,000 miles around at the equator. So you'd have to go about 1040 MPH to maintain your position with the sun. Less if you're away from the equator, but still way faster than solar craft are flying now.
"No fair, you changed the outcome by measuring it!" - Professor Hubert J. Farnsworth
This is the watershed performance for solar powered vehicles. If it can go through 2 nights, it can go through any number of them. Though we're still on the sunny side of the equinox (2 weeks prior), so there is a little more time charging in the sunshine than discharging in the darkness.
When a vehicle can go 24h on only 12h prior charge, that will be the next major milestone. Still not enough for uninterrupted travel past a latitude where nights are longer than a whole couple of days (depending on the battery - a yearlong discharge battery would be good anywhere with current performance).
The next parallel milestone is automated rechargers leaving ground charging stations to recharge the permanently aloft vehicle in flight.
After that, there's not a lot more demand for improvement, except overall efficiency for carrying heavier loads and more demanding equipment.
Like a network of these permanently in high atmosphere propelling solar sails through the solar system and down to blimp spaceports.
--
make install -not war
I have an idea- how about mounting some LEDs on the wings which could help boost the amount of light the solar panels recieve? You could keep going for like, forever.
Replace the wings with an envelope and you can stay up for weeks.
Deleted
Not only did I submit this story with no type-o's, last night, but I also made reference to the previous solar powered flight that lasted 2 nights, which this submission implies never happened before.
Though the previous one also did gliding/non-powered flight part of the time. Still, up for 48 hours.
Lisa, in this house we OBEY the laws of thermodynamics!
Speed of sound = 1225 km/h.
I am going to be pedantic and point out that the speed you give is at sea level, looking this up in wikipedia I read that the speed of sound in air is not heavily dependent on air pressure but more on temperature (it is slower as you go up since it gets colder).
At 29,000 the speed of sound is merely 1083 km/h.
Check out this press release.
AC Propulsion said that they could do it indefinitely, but their pilots got worn out.
Thad Beier
I love Mondays. On a Monday, anything is possible.
I think the quantity of energy that it takes to go over 1000 miles an hour is going to be pretty hard to collect in a solar powered plane.
Like many space and exotic aircraft, it must have to expend a lot of energy to get to its cruising altitude. Once that's done, conditions should become easier. Would it be considered 'cheating' to launch such a perpetual flying machine with an assistance device? That could be either disposable batteries that are jettisoned when discharged, or some chemcal rocket engine, or a jet engine, or have it launched from an aircraft.
Insolation is going to me much better at high altitudes. I just hope the photovoltaic cells are designed to take advantage of the increased amount of energy available in the UV spectrum. How about filling the free space in the wings with hydrogen? That might help lift a little, at least from the ground. However, there would have to be some way of dealing with the reduced pressure at operational altitude.
There's been a lot of interesting improvements in PV efficiency lately. However, most of these seem to only happen when the cell is operated at insolation far above normal. These are obtained by focusing the sunlight. Unfortunately, all of the technologies I know of which could do this are heavier than simply adding more, less efficient cells which operate at normal insolation or the slight improvement that high-atmosphere flight provides.