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Comments: 200 +- Technology: High-Tech Blimps Earning Their Wings on Wednesday August 26, @07:35PM
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by
samzenpus
on Wednesday August 26, @07:35PM
from the truly-goodyear dept.
from the truly-goodyear dept.
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technology
coondoggie writes "The US Army this week showed off its latest high-tech blimp laden with powerful radar systems capable of detecting incoming threats 340 miles away.
The helium-filled blimps, or aerostats, are designed to hover over war zones or high-security areas and be on guard for incoming missiles or other threats. The Army wants them to reduce some of the need for manned and unmanned reconnaissance flights.
The aerostat demonstrated this week is known as the Joint Land Attack Cruise Missile Defense Elevated Sensor System (JLENS), which is designed to fly up to an altitude of 10,000 feet. According to GlobalSecurity.org., the $1.4 billion JLENS is a large, unpowered elevated sensor moored to the ground by a long cable. From its position above the battlefield, the elevated sensors will allow incoming cruise missiles to be detected, tracked, and engaged by surface-based air defense systems even before the targets can be seen by the systems."
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blimps (Score:2, Funny)
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Even so I'll stand by my troll ha ha ha :)
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1.4 billion? What is that describing? (Score:2, Insightful)
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Blimps (Score:3, Interesting)
Re:Blimps (Score:4, Informative)
Parent
Shoot down at 10,000 feet is easy (Score:4, Informative)
I hate to pop your balloon (pun intended) but 10,000 feet is not that high. In World War 2 the Germans had anti-aircraft guns that could easily get to much over 20,000 feet. Many cheap modern shoulder held anti-aircraft missiles can easily shoot this high and a blimp would be easy to hit. It might be safe from small arms fire but a few small holes wouldn't hurt it much. An anti-aircraft missile is another matter.
Parent
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So....you're saying that the aircraft is going to be vulnerable to anti-aircraft missiles. Stop the presses.
Really. If the blimp can be built cheaper than an airplane/UAV, and cover loads more area, then it getting shot down would be unpleasant, but a loss less expensive than losing a plane, its fuel, its weapon payload, its pilot, and so on.
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So....you're saying that the aircraft is going to be vulnerable to anti-aircraft missiles. Stop the presses.
Really. If the blimp can be built cheaper than an airplane/UAV, and cover loads more area, then it getting shot down would be unpleasant, but a loss less expensive than losing a plane, its fuel, its weapon payload, its pilot, and so on.
And if the blimp is cheaper than the anti aircraft missiles you might have a net benefit right there.
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Note: on further investigation, it seems that we are talking about 12 or 24 blimps. Taking 24 that puts the cost at 58.3 million. Given much of the costs are in ground facilities and development, but the total cost is just too high for something that can easily be shot down. The entire program sounds like the infamous $800 toilet seat the military paid for.
Re:Shoot down at 10,000 feet is easy (Score:5, Interesting)
Well, yes, artillery is referred to as "guns", but that's a bit misleading, don't you think? If the bad guys have managed to move artillery pieces that close to your base of operations, you've got bigger problems than whether or not your blimp gets shot down.
Yeah, most modern shoulder-launched ground-to-air missiles could get a lock at that range, but most of these missiles also use infrared guidance. Would a blimp give off enough of a heat signature for a lock?
Parent
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But the blimp is for missile defense. What sort of adversary would have missiles but no antiaircraft guns? As for closeness, all sorts of weapons are more easily smuggled on the surface than launched by missiles, so missile defense is pretty futile.
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Plus, there is the risk factor in smuggling. If you are caught, often the agent will be caught alive and may give away secrets. Rockets don't do that, you launch one from the roof of an orphanage and then drive off before the rocket even hits the ground. Even if someone does sp
Re:Shoot down at 10,000 feet is easy (Score:5, Funny)
I hate to pop your balloon (pun intended) but 10,000 feet is not that high. In World War 2 the Germans had anti-aircraft guns that could easily get to much over 20,000 feet. Many cheap modern shoulder held anti-aircraft missiles can easily shoot this high and a blimp would be easy to hit. It might be safe from small arms fire but a few small holes wouldn't hurt it much. An anti-aircraft missile is another matter.
True.
Blimpin' ain't easy.
Parent
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Re:Blimps (Score:4, Insightful)
Parent
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And if this is in any way related to the blimp system they're testing near the Sarnia Canada border [thestarphoenix.com] (which I'm betting it is), they don't do so well with lightning either.
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Yah, those lead-lined clouds cause huge problems for our radar arrays ...
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The blimp has a radar system that allows it to detect all flying objects (missiles, airplanes, rockets) before they reach it - that eliminates the danger from radar sensitive missiles. Since it isn't metal and doesn't have any heat sources, radar guided and heat guided missiles aren't going to be much use.
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The thing is huge and doesn't move, making the guidance task of whatever you shoot at it very easy.
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There is more to a blimp then a big gas bag. There are engines, a crew area, weapons, fuel and probably a whole lot of other things. Most of those arn't going to react well to bullets.
As for your claim that blimps were hard to shoot down in WWII:
The US was the only major power to use blimps in World War II. These were generally used for non-hazardous and anti-submarine patrols. Given a U-boats tendency to flee from an airborn threat anti-submarine threat wasn't someplace where they would really encounter he
Re:Blimps (Score:4, Funny)
Parent
Overpriced (Score:2, Insightful)
$1.4 billion dollars? We are talking about what is basically a balloon with an instrument package slung beneath it, aren't we? I don't know about you, but I'd be willing to bet that if the purchaser was anyone but the Pentagon, the price would be at least an order of magnitude lower.
Re:Overpriced (Score:5, Insightful)
Parent
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Sure, but they're not just paying for the defense, they're paying for the sticker, for the -status- that a Rayethon brings. You cruise around in a lockeed blimp, people ignore you. They see "Raytheon JLENS" and they want to know who you are, the valet makes sure not to scratch the doors.
In seriousness, it looks like raytheon built them. Their wiki page on them lists several controversies [wikipedia.org] that seem pretty typical of the industry [wikipedia.org].
Another blurb on JLENS I found (http://defense-update.com/products/j/jlens.ht
Re:Overpriced wrong price (Score:5, Informative)
That billion dollar price includes the communication system between the aerostats radar and the targeting radar of other systems like anti-aircraft missile systems. So it is a very misleading number. I would guess the "blimp" or really aerostat part is less than 5% of the total cost. This is really an integrated detector system that happens to use a blimp as one of its inputs.
Parent
And... (Score:2)
Yet it still can't detect the low-tech truck bomb or suicide bomber that is the biggest current threat.
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Yes you can: if the truck or suicide bomber has strapped himself to the side of a missile!
Why Helium and not Hydrogen? (Score:3, Interesting)
I saw this thing the other day about the Hindenburg and how it wasn't burning hydrogen that the world saw, but rather it was the doping compound used on the outside of the airship. Turns out the majority ingredients used in the compound are the same ones we use today... in solid rocket boosters! (The 3rd Reich knew about it back then but blamed the use of hydrogen to save face.)
Hydrogen is lighter and is easier and cheaper to create. So I have to wonder why it's not being used.
Re:Why Helium and not Hydrogen? (Score:5, Interesting)
This page [www.zyra.tv], despite the horrible colors, does a pretty good job of explaining why helium is used instead of hydrogen.
The main reason to use helium is that hydrogen is indeed flammable, even though it may not have caused the fire on the Hindenburg, it's still highly reactive to oxygen.
From the link:
Hydrogen (atomic weight 1, but exists as pairs of atoms (diatomic), molecular weight 2), should weigh 2g per 24 litres at room temperature, whereas Helium (exists as lone atoms (monatomic), atomic weight 4), should weigh 4g per 24 litres at room temperature. But the mistake is to think that this would automatically make it float twice as buoyantly. The fact that's important is not the weight of the gas in the balloon, but the weight of the air which it displaces.
[...]
Both Hydrogen and Helium weigh almost nothing for the purposes of buoyancy in air. In contrast, air is mainly nitrogen, as pairs of atoms, which has a weight of about 28g per 24 litres at room temperature. To put some figures on it, a 24 litre helium balloon would seem to weigh 4g minus 28g = minus 24g in air. In comparison a 24 litre hydrogen balloon would seem to weigh 2g minus 28g = minus 26g in air. -24g or -26g, take your pick? The difference is about 8%.
So basically, you're either flying a safe blimp, or a giant bomb with 8% better buoyancy.
Parent
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Adding to the above post, hydrogen is much harder to keep contained over He. After all, it's just a proton.
Re:Why Helium and not Hydrogen? (Score:4, Informative)
No. Two protons. Atomic hydrogen is pretty much never seen in nature. It's always bonded as H2. I think that's actually a slightly bigger molecule than mono-atomic He.
Parent
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Lol, you're right as it's diatomic. I'm a chemist, should have caught that!
Fail.
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Hydrogen is not actually much lighter than helium. What matters is not the molar mass, but the difference between the molar mass and the average mass of air - this is what generates buoyancy. Hydrogen is 2 g/mol, helium 4 g/mol, air approximately 29 g/mol (it is a mixture, so that's the average value). Ths means that 1 mol (about 22,4 l) of helium will lift 25 g, and 1 mol of hydrogen - 27 g. Therefore hydrogen is only 8% better than helium.
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Irresponsible waste of nonrenewable resources (Score:5, Informative)
The amount of Helium on the Earth is very small (though there is lots in space). Helium is needed for medical MRIs and scientific research, but we are going to run out in a few decades. My lab is already suffering from increased Helium prices. Helium has a nasty way of escaping from containers (we're only able to recycle about a third of what we use), so these blimps are likely to waste a lot. Just like the rest of the missile defense systems, they'll never be used for their intended purpose.
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If it's really that scarce non-renewable, people could make big bucks buying it now and storing it for a few decades. People right now either think that the price is fair --- (helium price now + cost of N decades helium storage + financing / opportunity costs) >= (helium price in future) --- or people are being stupid/oblivious to opportunity.
Perhaps you and your finance buddies should get a helium futures ETF started? It's a commodity play, and people are worried about inflation in the next few year
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What comes to mind is that, as far as I know, we only use helium for three things... lighter-than-air stuff, as a neutral gas in very deep dive air tanks, and as a coolant for nifty medical and sciency devices. Part of the reason, IIRC, is that it's just that it's a relatively cheap byproduct of existing oil and natural gas mining. But we could just as easily use hydrogen for the lighter-than-air stuff and other gases or techniques for the coolants. I'm not so sure about the diving, but then, we use a hell
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Liquid helium is pretty unique as a coolant - it boils at 3-4 K, and is needed to cool the core in superconducting magnets. Everything else has a much higher boiling temperature (quickly scanned off of wikip) - 20 K (hydrogen) 77 K (nitrogen) or 90 K (oxygen, paramagnetic - no good for superconducting magnets anyway).
It's also pretty standard to measure well below 20 K - down to mK in some experiments - and you can't do this without sucking hard on LHe. I'm not an expert but I use LHe a lot and I don't know
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I eagerly await somebody's explanation of how the Free Market will conjure up a substitute...
As the price of helium goes up it will become worth it tap more expensive supplies of helium, and people will use less of it. This is pretty basic free market economics.
Unfortunately, because of their size... (Score:2)
... the blimps will be seen from over 1000 miles, and the single high-altitude high-speed stealth anti-spy missile will say hello, shortly thereafter. ;)
Bah. (Score:2)
I had no idea (Score:3, Informative)
So except for the US, who has a huge cruise missile fleet that needs to be guarded against?