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Virtual Earth Exposes Nuclear Sub's Secret
Posted by
kdawson
on Sun Sep 02, 2007 04:27 PM
from the tarp-would-have-helped dept.
from the tarp-would-have-helped dept.
NewsCloud alerts us to a story a few months old that has been getting a lot of play recently. A Seattle blogger, Dan Twohig, was browsing in Microsoft's Virtual Earth when he accidentally came across a photo of a nuclear sub in dry-dock. Its propeller is clearly visible — this was a major no-no on the part of someone at the Bangor Sub Base. The designs of such stealth propellers have been secret for decades. Twohig blogged about the find and linked to the Virtual Earth photo on July 2. The debate about security vs. Net-accessible aerial photography has been building ever since. The story was picked up on military.china.com on Aug. 17 — poetic justice for the Chinese sub photo that had embarrassed them a month before. On Aug. 20 the Navy Times published the article that most mainstream media have picked up in their more recent coverage. Twohig's blog is the best source to follow the ongoing debate. No one has asked Microsoft, Google, or anyone else to blur the photo in question. Kind of late now.
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Technology: Google Maps Shows Chinese Nuclear Sub Prototype 339 comments
mytrip writes "An image of what could be one of China's new nuclear ballistic missile submarines is available on the Google Maps and Google Earth satellite-image site, a defense blogger claimed Tuesday. The satellite picture was discovered by Hans Kristensen, director of the Nuclear Information Project for the Federation of American Scientists, and announced Tuesday on his blog. Kristensen believes the picture, taken by the Quickbird satellite late last year, reveals China's new Jin-class, or Type 094, nuclear ballistic missile sub. The new sub class is approximately 35 feet longer than its predecessor, the Xia-class, also known as Type 092, according to two images Kristensen compares on the blog. The Jin-class sub has an extended midsection that houses 12 missile tubes and part of the reactor compartment, Kristensen explains."
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Google Cache (Score:5, Informative)
Re:Google Cache (Score:5, Funny)
Clearly, the citizenry's desire to be on equal terms with its rightfully appointed overseers is misguided.
What could compare to the danger of such leaks? Only, perhaps, ability of the governed to guide the acts of the governors. (But, thank God and all that is holy, we need not contend with such a possibility.)
The proper solution to this satellite photo disaster is to establish government and international bodies, whose responsibility will be to oversee the propagation of information in its early stages. Press organizations, and other legitimately licensed speaking entities, could submit all reports and articles for government approval before publication, and thus dangerous knowledge would be stopped in its tracks. All information emanating from government bodies would be confidential by default, enforced by penalties befitting treason.
It is indeed a distant dream -- such a beautiful system of bureaucratic power and unquestionable hierarchy -- yet we must do what we can to stop out-of-control communication amongst the proletariat from further endangering the established, and righteous, distribution of power.
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Probably not significant (Score:5, Insightful)
Re:Probably not significant (Score:5, Insightful)
They are.
It did.
It almost certainly is real; it's too similar to other known quiet props, with some interesting variations that the 2-D satellite image did in fact usefully reveal (blade advance angle), from the sun angle and shadows.
Those in fact tell a professional in the field something useful about the operating capabilities of the sub, in terms of its relative optimization for different types of operations.
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Re:Probably not significant (Score:5, Insightful)
I tend to agree just because otherwise it would presume a really complicated hoax with a low chance of success (such as fooling a foreign government.) You'd have to replace the propeller, then make Microsoft or whoever takes pictures to take them, then you'd have to activate your agent to post the photos on a blog, and even then you'd still not know if the photo fooled anyone or not, since your adversary wouldn't be a complete idiot, so the fake must be realistic and mostly working.
With regard to the photo, what you have there is effectively one blade photographed from seven different angles. This allows the "other side" (whatever that is) to combine them to get a higher resolution.
But the main issue here is there are not too many countries in the world that would even care about such things. NATO countries probably don't need this photo, they have the real stuff. Russia is rumored to have procured such propeller designs about 25 years ago, and likely has enough computing power to improve on them as needed. China probably has many agents everywhere as well, you can't possibly keep such large things secret for long. What other countries then would want to know how to design a silent propeller, considering that even milling machines required to build the blades are not sold over the counter to anyone who asks, and they are not cheap either, and you have to have a solid manufacturing base to even produce the metal for the blades. So it's an expensive, high-tech business that only a handful of countries have the need and the money to get into. Not all major countries build submarines, many prefer to buy.
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Re:Probably not significant (Score:5, Informative)
The general shape is not news; it's the same general shape as on a bunch of US attack sub prop pictures which have been public for 10+ years.
The photo reveals the blade advance ratio for that particular prop design, though, which is useful to adversaries, and is different than the attack sub props.
As far as I know, and I have a naval architecture degree and have followed sub and naval ship design reasonably well for 30+ years, enough details to determine blade advance ratio on Ohio SSBN props have never been public. It was widely known that they were skew / scythe props. But "It's of that general type" and "Oh, look, that's what speed it's designed for" are two different things. A smart hydrodynamicist or naval architect can use that and tell roughly how fast an Ohio can reasonably be expected to go at top end speed, and things about how much cavitation noise it will make accellerating in a sprint. Also, it can help map propellor RPM to speed.
It's important, and the blade advance angle there is very different than the previously widely known ones on attack sub props, and that will tell bad guys something.
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Re: (Score:3)
I'd like to think that the naval engenieers who designed that thing didn't add blades just for the sake of it
Anyway, the propeller looks surprisingly like... a propeller. I was kinda expecting to see something completely weird with all that secrecy.
Re:Probably not significant (Score:5, Funny)
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Re:Probably not significant (Score:5, Funny)
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Re:Probably not significant (Score:4, Interesting)
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Re: (Score:3, Funny)
Re:Probably not significant (Score:5, Informative)
Why three?
I am not a fluid dynamicist. But: To increase thrust at a certain RPM, it seems that you can either (1) increase the diameter of the propeller, or (2) increase the number of blades. The problem with increasing the diameter is that the velocity at the tips increases, which leads to effects like cavitation (which, besides being very noisy, damages propellers). So what you do is increase the number of blades.
Prop-driven airplanes produced near the end of WWII had many-blade propellers for this reason as well: They wanted a lot of thrust, but, if they made the blades any longer, then the tips would have been supersonic. (I think I got this factoid from the History Channel.)
My guess is that a quiet high-thrust propeller would spin slowly and have many, very wide and heavily-curved blades. Let's see if somebody who knows more agrees.
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Re:Probably not significant (Score:5, Informative)
One thing the article doesn't point out is that increasing the solidity of the propeller disc can have it's own consequences, and there is generally an optimum solidity (depending on various other factors) which results in the highest efficiency.
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Re:Probably not significant (Score:4, Interesting)
Next time you get on a 777, just think, you are riding on one of the most advanced propellor aircraft in the world.
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Re:Probably not significant (Score:5, Funny)
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Re:Probably not significant (Score:5, Insightful)
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Re:Probably not significant (Score:5, Informative)
The purpose of having an odd number of blades is no secret - it is to reduce vibration. As the submarine travels through the water it leaves a wake behind it. Above the submarine there is less water pressure than below - so having two blades above and below at the same time is a bad thing. The more blades, the less vibration, but propellors are more efficient with fewer blades. You will see speedboat propellors with three or four blades, and fishing boats can have propellors with only two blades.
There is also the problem that having different metals in close proximity in a salt water environment, can lead to an electrolysis effect where the metals and water act as a kind of battery. Lots of technical papers on Propellor design [hydrocompinc.com]
"The most frequent cure for a singing propeller is the popular "anti-singing edge". This is a chamfer applied to the trailing-edge to promote separation of the vortices."
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Interesting for average joe, but... (Score:4, Insightful)
Re: (Score:3, Insightful)
Re: (Score:3, Informative)
Commercially available satellite imagery does not have the resolution to show you a photo of your house from orbit. Images used by the 'intelligence' communitity and the military have higher resolution, but not at the magnification that they'd like you to think they have.
From TFA: (Score:5, Informative)
Is it really so secret? (Score:5, Informative)
I think I remeber that the thechnology to make these kind of silent propellers where sold by a norweigan company to a KGB front in the early 1980:s. As I recall, it was a major scandal when the news brooke.
As I have understod it, most soviet nuclear subs had these improved propellers since late 80's and that most of the eastern block started to get access to the same technology.
Most western submarines has had these kind of silent props for years and I belive that most submarine nowdays have one.
You could try to track the Swedish HMS Gotland with passive hydrophone and see how far that takes you, for instance... she insn't even a NATO sub but she is more silent than even the american SSN subs.
Re:Is it really so secret? (Score:5, Interesting)
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Re: (Score:3, Interesting)
She can also run as fast as most nuclear boats for this time, so having a silent propeller is a major factor. And, I can tell you that it looks exactly like that one in the picture after having seen other Swedish sub propellers.
It's the Sound signature, not the noise level. (Score:3, Interesting)
The submarine will still make some noise. They would be concerned because knowing the propeller design gives you an idea of what type of noise it will make in use
The signature can be used to identify classes of submarines and potentially individual subs.
So rather than other countries copying it
On the other hand, maybe the US doesnt care at all
Face it.... (Score:3, Interesting)
Re:Face it.... (Score:5, Funny)
Okay... So what's sitting on the topmost shelf of the rightmost cabinet on the east side of the wall of my garage?
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Link to base since the blog is hosed (Score:5, Informative)
Coordinates are +47 43' 39.58", -122 42' 55.83" for the base (this can be plugged into Google Earth.)
The location of the snapshot is of the dry-dock at 4744'36.08"N, 12243'48.51"W.
This link may or may not work: http://maps.live.com/default.aspx?v=2&cp=ryqjnb4s5 7d5&style=o&lvl=2&tilt=-90&dir=0&alt=-1000&scene=1 0352732&encType=1 [live.com]
There's no propeller visible in the Google Earth imagery. All you can see is that there's what might be a sub; it's quite blurry. The Windows Live imagery shows a blurry whirly instrument of death; looks like a bunch of boomerangs.
Honestly, it's stupid. Half the shit that's classified, is just classified to impress. For example, the top speed of various US air craft carriers. Like that can't be figured out by a foreign government...? Like our *propeller technology* is that much more advanced, and other nation's subs haven't figured out what it sounds like? C'mon.
Re:Link to base since the blog is hosed (Score:5, Interesting)
I rode a Fast Attack in the Cold War, so I might know more than someone who hasn't been there.
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movies (Score:3, Interesting)
Anyway, I could be wrong, but I think I've seen one before.
Behind the times (Score:5, Insightful)
The props haven't been as jealously gaurded recently as in times past - in fact, I saw pictures openly published of them as early as the late 1990's. Though the less knowledgeable may drool over seeing them at all - the pictures on Virtual Earth are not particularly high res, nor particularly useful. The fact that the US uses scythe blade propellers has been openly acknowledged since the early 90's.
Or, to put it even more simply, these pictures show nothing not already publically known and acknowledged.
Ditto for the weapons magazines - there is nothing classified about the exteriors, existence, or location.
This article is however a interesting point on the problem of getting your news from blogs; sometimes the author knows what he's talking about. Usually, when it comes to specialized topics, he doesn't.
Setec Astronomy? (Score:5, Funny)
another pic of the same technology... (Score:4, Informative)
...is this a secret?
Re:The US Navy Is Not Such A Secret (Score:5, Insightful)
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Re:The US Navy Is Not Such A Secret (Score:4, Interesting)
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Re:The US Navy Is Not Such A Secret (Score:5, Interesting)
And where did that factoid come from? One would imagine that a ship with the capability to strike at extremely long distances is always useful, if you can hit your enemy before their weapons can reach you you have an advantage. As for carriers being vulnerable to subs that's only partially true. Certain types of submarines, especially advanced nuclear subs (and diesel ones, so long as they don't surface anywhere near the carrier group and have enough battery power to get in and out) could conceivably slip through the defenses around a carrier and then it's aircraft would be useless. Given that the last major (that I know of) engagement between large groups of submarines and carriers was WWII, and that was clearly decided in favor of the carrier groups (53 u-boats sunk to less than 10 of the CVE mini-carriers) I'd say a generalization like 'Subs counter carriers' is kinda...wrong. A carrier battle group at war would typically have at least 1 radar plane (Orion?) on CAP. If the sub surfaces nearby radar has a chance of picking it up. In addition the carrier's escorts have darn good sonar and wouldn't be too hesitant to use it.
So basically, 1 lone carrier vs sub is an easy win for the sub, unless the carrier sees it coming from a long way off and launches anti-sub efforts. 1 carrier battlegroup is at least a match for any similar number of warships, including subs, and very good at other tasks such as beach assault, long range support etc. A carrier battle group is currently the most versatile type of navy imaginable, as such it may not be the best way to counter all threats (a pair of destroyers working in tandem with some anti-sub helicopters would be cheaper and pretty effective against small numbers of subs). It's a Jack of All Trades, master of none type of thing, a Carrier group is good at anti-surface ship, anti-sub, and anti-land combat.
Sneaking up on a ship which is fully prepared for war is a lot harder than some things would lead you to believe. Just because you're underwater and pretty quiet doesn't mean your undetectable, and if you're too quiet you can be detected that way (one possibly problem with modern US subs is that they're actually quieter than the surrounding ocean and could *conceivably* be detected that way). No amount of noise-reduction is going to save you if even 1 enemy ship is using active-sonar, you're going to be detected unless it's a cloak-and-dagger fight which is something aircraft carriers rarely engage in, they're more 'Hey look, I'm right here, I don't need to hide because I'm that much better than you' style fighting, and in that arena (when radars are at full and sonars are active) subs lose all stealth benefits, and an unstealthed sub vs a carrier group is just asking for trouble.
So to sum it up, no, a carrier battle group is not useless. Subs are easily countered (unless you're trying to be stealthy as well) and missile blocking is what Aegis (common in CBG's) class destroyers were partially built for. Aircraft carriers are built for show, and are good against weaker enemies, but also against equals, it's against stronger enemies (few and far between at this moment) that they begin to look impossibly weak and fragile.
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Re:The US Navy Is Not Such A Secret (Score:5, Interesting)
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Re:Sinking the U.S.S. Reagan (Score:4, Funny)
Well, what did you expect ? They're vikings, for pete's sake ! Half ninjas, half pirates, half polar bears ! They rape, pillage and plunder, and then they flip out and get really mad ! Even Nazi Germany and Soviet Russia knew better than to fuck with them !
Just be thankful they used a wussy submarine and not a Viking longboat with a dragon on the bow - then it'd really have been a massacre.
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Re:The US Navy Is Not Such A Secret (Score:5, Informative)
Source [fas.org]
Also read about the low amount of use China's submarine fleet gets, and the inexperience they have: Source [fas.org]
This basically amounts to China having never actually used their submarines as a nuclear deterrent, and since they have no ICBMs that can reach the US they have no nuclear deterrent against the US and a comparatively very limited navy. (Report [fas.org])
The media loves to hype up China's military spending, but if you think China's grounded 1980's built subs, or the speculated five new Jin-class (Type 094) subs [fas.org], are going to make the US Navy "ineffective", or if you think aircraft carriers (the most expensive ships of all) are just for intimidating small nations, then you're a few warheads short of a nuclear power.
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Re:The US Navy Is Not Such A Secret (Score:4, Insightful)
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Re:The US Navy Is Not Such A Secret (Score:5, Insightful)
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Re:The US Navy Is Not Such A Secret (Score:5, Insightful)
The German U-boat fleet rarely engaged the Royal Navy. And with the occasional exception, when they did this, they were sunk. The U-boats were used as commerce raiders, and had great success. For a year or so. Now please look up the statistics on how many u-boats actually survived the war, and talk to me about "success". It was a disaster, like almost everything else Germany did after taking France.
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Re:The US Navy Is Not Such A Secret (Score:5, Insightful)
Oh I dunno, some 500 years of British naval combat experience perhaps? Plus the Brits had the numbers on their side. Technology will only help you so far, but numbers win every time.
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Re:Slashdot (Score:5, Interesting)
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They fucked up. (Score:4, Insightful)
The issue here isn't that "Google or Live didn't blur it out". It's that the base people didn't care much for the eyes in the skies. I'm sure the Chinese (or Martians) have seen the secrets.
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It's older than that... (Score:4, Insightful)
In reality, if they censored the images the only people who wouldn't be able to see it are people not willing to spend money to see images of a classified submarine. Any country/organization with it's own program for developing nuclear submarines or technology to detect submarines likely has the financial/organizational resources to aquire this imagery without depending on a free website.
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Re:Slashdot (Score:4, Funny)
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Re:Pay attention to the missiles, not the propelle (Score:5, Insightful)
Google says you're not the first, but what the hell...
That's almost precisely backwards. These submarines exist to ensure that never happens. They're part of the Mutually Assured Destruction balance. Neither side is going to launch a first strike unless it knows with absolute certainty that it's going to come out sufficiently ahead in the ensuing trade-off to survive as a viable state. Nuclear subs completely screw with any certainty you might think you've got in launching that attack, because it's damn near impossible to know that you'll be able to kill enough of the opposition's subs before they can launch. Stealthy propellers are a big part of that, helping to ensure that the enemy can't get and keep a lock on your position. These submarines aren't designed as first-strike weapons, but as an assured second-strike. To say that this technology cannot be used completely misses the point. In just existing, they are being used - as an insurance policy. If they were ever to launch, humanity would already be dead.
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Re:The real secret (Score:4, Informative)
And I was exposed to all branches for long periods of time. You will not find a less gay friendly place than the Navy. Even the Marines are more tolerant. It's because of the hollywood archetyping of the navy as gay that the navy has had such a buildup of anger about it. The 1993 DADT policy greatly increased the problem, and violence against gays has increased by about an exponent from 1993-1999 (no idea of the exact recent statistic, but it has increased greatly up to today)
Gays int he military are usually quite good. dedicated to serve in spite of additional hassle. The Brits have been open for a while, and they are, man for man, extremely effective. I'm not implying that there is some kind of problem with gayness in the military.
But this is typical trash propaganda. Sounds ludicrously paranoid, but the fact is that there is an effort to portray soldiers as feminine weakling children or sociopathic monsters. You'll find most gays in the Army. You'll find the fewest in the Navy.
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Re:The real secret (Score:4, Insightful)
Of course, then you find out that "gayness" isn't something you can "drive out", it's just something you are. Then you become a jackass self-hating prick with a special chip on your shoulder about fags. Man, I tell ya' the USMC is rife with them.
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