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High-Altitude 'Security Blimps' Coming Soon
quackking writes "The AP is reporting (in New York Newsday) that the Georgia Tech spinoff company TechSphere has sold their concept of immense (300 foot diameter), high altitude spherical surveillance blimps to the honchos at Fort Benning, GA, and production is beginning now! (more here.) These things are as big as a 30-story building. Meanwhile Lockheed-Martin is working on gigantic 500-foot long robot blimps, (and more here.) This would be 25 times the size of the well-known Goodyear blimp. Says Mayor Don Plusquellic, 'For Akron, it's a very emotional thing.'"
... perhaps because one of the original US military airships was the USS Akron?
These blimps were actually aircraft carriers. Akron's sister ship, USS Macon, once "dive-bombed" a Navy ship carrying President Roosevelt, dropping a bundle of newspapers for his reading. The stunt was intended to prove the worth of aircraft against ship targets.
Toronto-area transit rider? Rate your ride.
The distance a gun will shoot striaght up is surprisingly limited; small bullets suffer from a great deal of drag and you actually can't neglect gravity.
Handguns are a non-started; you'ld need a large, specialized anti-aircraft gun to even think about it.
No, not just against Hawaii. They sent hundreds (or thousands?) of hydrogen balloons, to which they had attached simple fire bomb(s) towards mainland US. Intention was to try to start forest firest and other damages, and in general create terror in civilian population (ie. demoralize enemy). There was a very interesting documentary about that campaign; campaign itself was VERY top secret during WWII (esp. on US side). For once censorship did succeed; it (lack of news related to balloons) convinced japanese that plan wasn't working. Too bad there were actual casualties -- in couple of cases kids died when they went to look into funny balloons drifting in places like Montana and Wyoming. :-/
Wish I had link; I think you should find link to it from some PBS web site. There was also a map that had locations of every known instance of such a balloon found... and there were quite a few pins on it.
"History doesn't repeat itself, but it does rhyme." Mark Twain
rtfa.
Floating about 13 miles above the earth and holding a stationary orbit for 12 to 18 months,
Sure, you got a gun that can shoot 13 miles straight up?
Allegedly real newspaper headline from 1998:
Man Struck by Lightning Faces Battery Charge
6 people according to this source.
Civilian aircraft (including airliners) rarely fly much above 40,000 feet.
Shouldn't be a problem.
The biggest danger window would be during blimp acsent and descent.
"The more corrupt the state, the more it legislates." - Tacitus
Actually, hot air balloons were used as far back as the US civil war. (Sites include photos).
Great minds think alike; fools seldom differ.
Your typical 747 cruises between 36,000 ft and 44,000 ft. Air density starts thinning out dramatically at these altitudes hence the maximum possible altitude for a civilian aircraft would be say 50,000 ft (15.3 km straight up).
The only possible exception would a supersonic aircraft but there isn't too many of those in civilian hands.
Da ZombieEngineer
I live in Columbus, GA, which is basically the city Ft. Benning is located directly next to. Benning kids go to Columbus schools, I have many friends that live on post, etc.
:)
A little background - Ft. Benning is the largest permanent military installation anywhere in the world, taking up a full Georgia county. It's the home of the Infantry, and if you know anyone who's gone through jump training, regardless of branch of the military, they probably came through Benning. The place is huge, and is covered with trees, the majority of the land being undeveloped and used for firing ranges, survival training, etc.
I can see why they'd be interested in something like this; Benning is literally just too big to be fenced in like most military bases in this country. Depending on how much this costs to operate, it could be a very efficient way to keep the base at least a little bit more secure, which I see as a good thing.
Just thought I'd chip in with a local perspective.
Thats true. But considere the position of the earth:
During the early age of the solar system, while planets were still unformed, the inital blazing (with a lot more flux in the solar wind) of the sun pushed most light materials into the outer solar system (very rough explanation, i know). Thats the reason why the inner planets are no gas planets to begin with.
Now step 2: There was still a lot of helium remaining, but as the lightest gas (after h_2), it went up in the athmosphere and off into space. Its a slow process, because the bolzmann distribution isnt likely to give a atom escape velocety, but it happens. And they had 4 billion years of time...
The result is that nearly all helium on earth is the result of alpha decay (thats the reason why natural gas, of all things, is the best source of helium, at least on some oilfields: helium tends to collet in the same spots than the gas while going of from deeper layers of the earth)
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
There have been several posts to the effect of "what a big target, anyone with a gun could shoot these down". Consider the physics of this for a moment.
A Magnum-powered hunting rifle has a muzzle velocity of around 2,000 mph (You could try using an AK or such, but these are going to be considerably lower velocity). With the high-altitude blimps flying at 65,000 feet per the article, your shot would hit it in about 22 seconds, were it not for two things:
The first is gravity. 32.2 feet per second squared downward acceleration. Vith v^2/2*g = 131,400 feet maximum height, there is high enough initial velocity to hit the blimp.
The second problem, however, is air resistance. The aforementioned bullet loses half its velocity within the first 1,800 feet or so even in level flight, and continues to slow down from there.
Between these two considerations, there is no way for a bullet (except maybe from a huge cannon) to hit something that is 65,000 feet up in the air.
Even if you did hit it, a blimp is not going to suddenly pop like a rubber balloon. You might get lucky and hit a motor or some other critical component, but just hitting the surface of the blimp (which is what makes it such a big target) is just going to put a 1/3" hole in something as big as a skyscraper, and make it leak at a negligible rate.
Keep in mind that thousands of these were launched, and only a few hundred were found, many of them are probably still sitting around on the west coast..
There was also a japanese plane that launced from a sub, and tried to drop incediaries in the forest of the oregon coast mountain range. Of course, forest fires don't happen in Oregon in winter, we don't tan, we rust!!
Oh, and a torpedo was launched from a japanese sub at Camp Rilea (Spelling??, now a national gaurd base) but they didn't take into account the slow slope of the beach, and the torpedo just ran up on the beach and never went off.
What are we going to do tonight Brain?
The higher you go, the farther you can see. I don't recall it exactly, but @ the beach, you can see something like 22~25 miles out to sea. Raise yourself 20 or 30 feet and your viewing distance increases tremendously.
If you're standing at the edge of the water, the horizon is less than three miles away. At 30 feet, it's six and a half miles.
At 65000 feet, it's 314 miles away.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
Better yet, check this out for the free online version.
"(1) COMMENCEMENT.--Not later than January 1, 2005, the Secretary shall commence offering for sale crude helium from helium reserves owned by the United States in such amounts as would be necessary to dispose of all such helium reserves in excess of 600,000,000 cubic feet on a straight-line basis between such date and January 1, 2015.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Rigid airships are a lot more complicated to build structurally, since they are carrying a bunch of rigid structure that does nothing to generate lift and can bend and break under stress. Blimps are not just one big ballon, but can and are compartmentalized for disaster containment. Blimps were built in large numbers during WWII as patrol craft, and operated in the US Navy in that role up to sometime in the 1960s. The USN gave up on rigid airships in the 30s, essentially after the Shenandoah went down in a storm.
Balloons are not blimps because they don't have maneuvering engines. A spherical blimp would have engines that move it, making it more than a balloon.
(An untethered Kite or parachute with an engine is called an ultralight, or an airplane)
One of the big issues with these proposals has been power generation and storage. The solar generators that are light enough and flexible to go on a blimp body have tended to be low efficiency compared to heavier crystal cells, according to this, though there are claims here that new products can do nearly as well.
Batteries are notoriously heavy, so it's a tradeoff that hasn't been economically possible yet. Things need to be efficient, light, reliable, and cheap enough. The proposed HAA is still using old lead-acid batteries! I guess this works if there is enough helium, and low enough power demand (related to low wind speed to fight).
here is an article that describes this in more detail.
-dB
"It if was easy to do, we'd find someone cheaper than you to do it."
Actually, people like me have been using the strategic helium reserve for years. I'm a physics grad student who uses liquid helium for cryogenics experiments, and about half of our helium comes from the reserve, with the other half coming from coal mines and oil wells. I'm too young to remember it, but the old guys in the physics department remember when helium was $10-20 per liter (liquid), whereas now it's about $5-7 thanks to the Feds selling it cheap.
As usual Wikipedia has some info: try Fire Balloons.
As a rough rule of thumb (in imperial units):
Take your height above the ground in feet, multiply by 1.5 and take the square root to get the visible horizon in miles.
For a six foot person this would be sqrt(6*1.5)=3miles. If they moved to 150 feet it would be 15 miles......
- Helium is too light to stay around Earth's atmosphere for long.
- Hence Helium can be found trapped underground near natural gas, oil wells etc.
- Helium is naturally produced in quantity on earth as a result of alpha particle decay. As you may recall, an alpha particle is basically the nucleus of Helium. Personally, I'd have thought this means Helium would get trapped in substances like granite, but shrugs.
As to the theory that most deposits are in the US, I find that hard to believe, though I haven't heard of the theory or its justification.
We won't run out of Helium (as it is naturally produced), but it is certainly possible for us to have a major shortage if (say) speaking in high pitch becomes fashionable.