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Lockheed's High Altitude Airship
swordboy writes "Lockheed Martin has just awarded a contract to UniSolar Ovonic regarding development and delivery of flexible, lightweight solar cells for the U.S. government's High Altitude Airship security project. The proposed 500-foot-long dirigible is to fly at a stratospheric 70,000 foot altitude - above both jet stream and severe weather. The thin-film solar technology, although low in peak conversion efficiency, can potentially deliver a whopping 2500 watts/kilogram. This is the same technology as the previously discussed GE organic LED project - just with the physics in reverse. Broadband communication blimp, anyone?"
Unless it's powered with a FLOATER
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Mildly terrifying, at least.
"Prepare for the worst - hope for the best."
The organic LED based technologies (polymeric / organic /nanostructured / Titania / Gratzel / Graetzel) cells are not yet ready for prime time, though they have huge promise. Check out Konarka or Nanosolar. GE and HItachi are also fooling around with this. The idea is that you can make solar cells out of TiO2, which is almost infinitely cheap in industrial quantities (see here toothpaste or white paint.)
Uni-Solar's product is in fact based on conventional silicon, just like 90%+ of the market today. The difference is that instead of slicing it out of crystals, they sputter it onto a backing, enabling them to make, e.g. peel-and-stick solar panels for commercial raised seam roofs, a conventional shingle for residential roofing, as well as, here, a flexible backing product for airships. Many are working in this area; it's sort of the next generation for solar cell cost decreases (which have come down by more than half in the last ten years; world production doubled between 2000 and 2003 - however, we're going to run out of tricks with conventional silicon within about 5 years at this pace.)
I find everyone's obsession with conversion efficiencies touching; what sense does it make when your fuel source is infinite and free? Area - related costs are subtle, so focus on this: with solar, efficiency matters not at all - the be all and end all is cost per watt.
Just so somebody else doesn't have to look this up, geosynchronous orbit is at 19,323 nautical miles, while the various radar and broadband blimps are proposed to be at around 12 miles up. So satellites have an inherent 100ms delay each way, the blimp version would only have a one-way delay of 0.06 ms.
Geostationary satellites operate at something like 23,000 miles, so the delay is only about 1/4 of a second... 23,000 miles is far away, but electromagnetic waves are pretty damn fast. Also, that 1/4 a second probably doesn't matter anyway - the communication to from these satellites is typically passive/non-interactive; it's just broadcasting information back to Earth (e.g. TV signals) with no need for communication in the other direction.
I have read some feasibility studies for near-earth communications satellites, like high altitude blimps. The only real downside is the coverage area (since the blimp is much closer to the earth, the elevation angle is shallower). IIRC, they give pretty decent metropolitan area coverage, but not much beyond that. My antenna az/el calculator is at home. When I get back tonight I can post effective coverage areas if anyone is interested.
(S(SKK)(SKK))(S(SKK)(SKK))
Check out http://www.sanswire.com/
Global Tel (gtel) http://www.globaltel.com/ just bought Sanswire to use them for a broadband and voiceIP offering. The idea is that these things float above a city and service everything below it. They're thinking about not only offering this in major cities but also having them floating above flight routes of planes across the atlantic, etc, so you can have broadband/voiceIP while going transatlantic.
Very cool stuff, imho.
In many years of research, a NASA scientist at Cape Canaveral has found proof that neither the hydrogen in the hull nor a bomb was to blame, but the fabric of the Hindenburg's outer skin and a new protective coating. A single spark of static electricity was enough to make it burn like dry leaves.
What are we going to do tonight Brain?
Flamibility is not it's only drawback.
Most membranes are far more permeable
to hydrogen than they are to helium. As
a result, helium lasts longer, because
hydrogen escapes through the membrane
quicker.
They are a heavy engineering company. But they do indeed have a new ship which is flying now, the Zeppelin-NT:
http://www.zeppelinflug.de/pages/E/haupt.htm
Cargolifter were going to create a f*cking *huge* ship which with a cargo capacity of 160 tonnes but ran out of money. When I say "f*cking huge", imagine an ocean liner floating in the air in front of you.
http://www.cargolifter.com/
It seems that military spending is needed for these kinds of projects to succeed.
Government of the people, by corporate executives, for corporate profits.
My initial thought was that hyrdogen being a smaller molecule would leak out more rapidly, though perhaps not at a significantly higher rate. A quick googling reveals this to be false. Helium actually sneaks through mylar faster than hydrogen. At very low temperatures it looks to be about 50% faster. Dupont data, see page 3 I don't know what film they are using, but the others I checked were similar.
Given that the limiting factor for staying on station is gas leakage, hydrogen would seem to be a winner.
> If it gets shot or blown up...
I don't think gas type will be much of an issue. Either way the blimp will be a loss. The spectacular combustion of the hydrogen will happen well away from anything else that can burn.
The safety issues of hydrogen are probably only an issue on the ground. You probably would not want to put an inflated hydrogen blimp in the hangar for maintanence, so if the life cycle of the blimp involves hangar work like leak detection and repair helium looks better.
The final reason may be what Lockheed harps on a couple of times... Lockheed has the expertise in getting FAA certification for blimbs. The FAA is a variable that could effectivly kill the project, so project risk management probably dictates that they deviate as little as possible from the previous designs.
If that's the intended use. Perhaps they could team up with NASA which already has a winged flying prototype.
logical uses I can see are as replacements for cell towers
Not a chance, go read up how cellphone networks operate and you will see why this will not work.
cell towers need to be low, and lots of them in an area there are a very small number of frequencies and therefore you need to keep that number of calls in a cell area so that you can carry more calls in a geographical area...
cellular requires many small low towers to cover a metro area. you see taller towers in rural areas as the chance of saturating that cell site are much smaller in hickville compared to manhattan.
Do not look at laser with remaining good eye.
"The airborne laser will fire a Chemical Oxygen Iodine Laser, or COIL, which was invented at Phillips Lab in 1977. The laser's fuel consists of the same chemicals found in hair bleach and Drano - hydrogen peroxide and potassium hydroxide - which are then combined with chlorine gas and water. The laser operates at an infrared wavelength of 1.315 microns, which is invisible to the eye. By recycling chemicals, building with plastics and using a unique cooling process, the COIL team was able to make the laser lighter and more efficient while - at the same time - increasing its power by 400 percent in five years. The flight-weighted ABL module will be similar in performance and power levels to the multi-hundred kilowatt class COIL Baseline Demonstration Laser (BDL-2) module demonstrated by TRW in August 1996. As its name implies, though, it will be lighter and more compact than the earlier version due to the integration of advanced aerospace materials into the design of critical hardware components. For the operational ABL system, several modules will be linked together in series to achieve ABL's required megawatt-class power level."
Bush Lies On the Record.
SAMS developed by the former Soviet Union have been able to do that for years. And if a SAM is able to hit a highly maneuverable target moving at Mach 1, I don't think it's going to have a hard time hitting a target that's standing still.
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A shoulder launched SAM won't reach that high. If it did, terrorists wouldn't need to fire at planes near airfields. There just isn't a good way of packing enough propellent into that little missile without severely injuring the user.
Now if you want to talk about SCUDs...
Javascript + Nintendo DSi = DSiCade
This story was on Slashdot here and generally considered to not be worthy of submission. The article had a bit too much of a fantastical side to be given serious consideration.
And you got modded Funny instead if insightful!!! Where will it end?! Slashdot is obviously compromised. Lets make our last stand at K5
Aha. I RTFA and they're being paid to develop and deliver 2.5kW/kg solar panels. Their current designs put out 600W/kg, which sounds more reasonable. Hopefully they can come up with those 2500 things. That'd be pretty impressive.
If a job's not worth doing, it's not worth doing right.
A few years ago, I was military, and in Space Command, but nowhere where I could make policy. But we discussed things like this since I was in space launch. I predicted that, if satellite makers were smart, that balloons/dirigibles/flying wings would replace many, but not all, satellites. And this includes military satellites as well, if the USAF gets smarter.
Specifically, one of the things Air Force likes to talk about is operationalizing space, i.e., launching a satellite like it was a sortie of a fighter or bomber aircraft. That's not going to happen anytime soon, at least with the rocket types. But a squadron of high flyers with interchangeable electronics packages could easily be 'operational'.
However, for communications satellite, especially regional broadband communications (think army operations in Iraq), such a 'satellite', deployed when necessary, could be highly useful. Operations over, comm needed in Korea, send it there. It breaks, bring it down, repair and send it back up. Out of fuel/power send up the spare or just send up two. How many satellites can that be done for? When they are done (Hubble) the expense is enormous
Comm is not the only thing it could use a low-sat. Optics and Radar are prime candidates. Science, both looking up and looking down are possible. Even consider the GPS satellites. You do need your base system in space. However, if you needed increased accuracy in an area, put a high flying balloon/dirigible, flying wing, with the GPS innards and fly it in the general area. If done correctly, it could give receivers an additional satellite, improve the solution.
Our founding fathers removed the guys in charge. Be American. Vote incumbents out.
Check out where they plan on building these things. It's the old Goodyear-Zepplin Airdock in Akron, OH (now owned by Lockheed Martin - see their article on the HAA.)
A book I have (Published by Goodyear in 1923) lists this place as 1175ft x 200ft x 325ft. It even has a picture of it super-imposed over the American side of Niagara Falls (it's 75 longer). It's also mentions that it is so big that it often form clouds on the inside.
More links are here and here
This was suggested long before anyone actually built any sort of balloon..someone in the middle ages wanted to make a flying machine supported by evacuated copper spheres. Sadly it is not a goer, the weight of a structure able to contain a vacuum is far more than the density of the air displaced. At sea level you have to support a force of 14.7 pounds per square inch...for any practical sort of size this ends up being tons of load on the structure.
Heating the air to make it less dense works quite well of course.
The way I see it, the final product is going to have a payload capacity in excess of 20,000 lbs.
According to the linked articles the payload will be a mere 4000 lb, despite the dirigible's massive size. It makes sense, since an airship's bouyancy is created by the difference in density betwen the airship and the air around it. At sea level this large airship would have much greater lifting capability, but way up there the lifting gas won't be that much lighter than the thin atmosphere.
By the way, some back of the envelope calculations show that this thing would have about 70% of the volume of the LZ-129 , the famous Hindenburg. The Hindenburg was considerably sleaker too, at 804 feet long vs 500. The Hindeburg carried 50 passengers and 50 crew, which alone without luggage or cargo would amount to something like 15,000 lb; in addition, the ship could carry 11 tons of cargo.
So we're talkiing very neary 40,000 lb of payload capacity for the LZ-129 vs. 4000 for this beast. In part this is because of LZ-129's 40% greater volume (lifting gas only - overall it had 4x the volume), possibly the use of hydrogen gas (doesn't say whether the ship in question will use H or He). But mostly it is due to the fact the LZ-129's normal operating altitude was on the order of 200m.
An airship to lift 20,000 lb to the altitude this one will would, all other things being equal, have to have five times the volume. Conservatively, we are talking about something on the order of 850 feet long; possibly a bit less because of increased volume to surface ration. Undoubtedly it would be the largest flying machine every built.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
According to the link you posted, he was killed for helping the Iraqis perfect a missile that could have been used to launch attack Israel. Hell, they were even polite enough to warn him.
I don't mean to apologize for Israel here, because this was truly an ugly event, but it seems to me that the alternatives could have been significantly more costly in terms of human life.
There's also newton's law to consider.
Is this a troll?? Which law would you be talking about exactly?
Seriously - the rocket doesn't "push" against the platform when it takes off - it's the mass of the exaust gas being flung out "real fast" from the rocket nozzle that is the "opposite reaction" that sends a rocket skywards. If a rocket is just hanging in the air by straps or something and launched, instead of sitting on a base plate then it would take off exactly the same as if it was sitting on a launch pad.
In fact, a lot of the engineering done on NASA's launch pad was involved with how to redirect all that hot gas away from the pad via a huge duct so it doesn't turn the pad (and the rocket standing on it) into smouldering ash.
Nice try, but no.
If you were doing this in a sensible way you'd actually "fire" the space craft from the launch platform somehow (e.g. drop it).
The craft then lights its rocket and off it goes. It doesn't have to push _against_ anything.
Think about what happens in a vacuum...