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Detecting Stealth Planes
Zurk writes " Newsweek said China's new Passive Coherent Location (PCL) system
tracked the signals of civilian radio and television broadcasts and picked up aircraft by analysing the minute turbulence their flight caused in the commercial wavelengths. cool huh ? " They hope to use it to detect the F-117A and potentially the F-22. Very cool use of technology to fix a problem.
now they'll have to go back to building wooden planes ....
But, America can't start pointless wars without having a tremendously unfair technological advantage! This ain't right! Oh and if you think this will piss the Pentagon off, it won't. Those guys are in the business of constantly building new weapons of war. This and things like this will only strengthen their case to allocate more funds for defense.
This technology appears to be picking up planes by looking at the turbulence that they leave behind.
Why can't a series of unmanned rockets leaving turbulence all around jam this?
Another issue: if you are following the trail, how good is your fix on its current location? If it was in straight-line flight, OK. But if it was in defensive maneuvers?
Hmmm...how well does it work in different weather conditions?
There are a lot of questions here. Sure it is a cute step, but this is not the final solution and the race will continue.
Cheers,
Ben
My usual seat in the cluetrain is at A HREF="http://pub4.ezboard.com/biwethey.ht
Of course you can detect a stealth plane. You can detect a stealth anything. It exists, therefore it interferes.
;)
I believe it's the Typhoon class submarines you can detect by listening for silence in the waters. The submarine is so ``stealthy'' that it's more silent than the water that surrounds it. Blammo!
I would have thought that satellites would have been the first to be used to track stealth aircraft. If you track how the earth reflects a radio signal (radar), and then suddenly something breaks the usual reflection (a stealth plane will break the reflection, but it will not reflect much back itself) you know where to aim.
Isn't it just fantastic what can be done with technology today
well.. if they fly low enough, you could just hire some low paid marine to point and say, "Hey! There's a plane!"
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ping -f 255.255.255.255 # if only
I remember reading something similar a few years ago. Back then (this was a few years stealth planes first made their mark on the battle fields in Irak) the Australians had developed a radar device that could track these planes by the turbulence they generated.
...
Turns out that the shapes these planes were built to, which gives them their low radar profile, was very bad aerodynamically (in the sense that it caused a lot more turbulence than traditional planes would) which in turn enabled this radar to locate the turbulence. Not sure what happened to this project since, but the idea of tracking stealth planes by the turbulence they cause, is nothing new
Curiosity question... whoever submitted the story basically copied the text directly from the web page. The story (at cnn.com) directly attributes Newsweek, but the words are from a Reuters story (copyright 1999, all rights reserved, no permission for redistribution). Since this is unattributed and more than just a summary, is this fair use?
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Ian Peters
Just because a technology was developed by the Chinese does not mean it's bad. Have you ever considered that what was developed was a press release, or maybe a few well planted leaks? Both sides of the Cold War did this for years, and still do it. Using the media to plant seeds of doubt? Think Viet-Nam, Korea, Tokyo Rose in WW2. None of this is new.
Now if the Chi-Coms have invented and put into practice this technology, it only means we need to find a way to circumvent it. Say, by bombing TV and radio stations first.
Really folks, we have bigger problems to worry about. You know, the Chinese has the first compass. They kept it in a room and never used it until Marco Polo showed up with his. They pulled it out and said, so what?
Don't forget it was a Russian scientist who invented Stealth. He published a paper that inspired our development of the prototype.
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I saw a wierd vapor trail in the sky once through my telescope (while observing the sun). I removed the solar filters and observed the trail. It was a single trail with what looked like periodic rings around it. Like a string from an abacus made with skywriting. Rumors (all we have to go on) is that this is some kind of high speed, high altitude, military spy plane from the US. The plane operates by essentially firing off a periodic serpes of explosions to propel it (hence the ringed trail). Anyone know more about this?
Lockheed-Martin has a web page for their Silent Sentry system. Not much in the way of technical description but it can't be that secret if they put it on the web.
Mea navis aericumbens anguillis abundat
Couldn't you just randomly add bursts of these commerical signals (but broadcast from all over the place) to basically add a lot of "noise" to the data. Sort of like /. at -1.
This device is passive, meaning it doesn't emit any RF to detect. Conventional radar emits microwave energy, and allows for countermeasures (by homing in on the radar source). This system, if my interpretation is correct, detects the plane based on civilian RF (e.g., FM, AM, etc.) noise. If this technology does not depend on single sources (e.g., large radio towers), but rather a multitude of smaller civilian emissions, it would be very hard for the US to squash, atleast not without causing a lot of collateral damage. That is a pretty big technological leap; not yet developed/implimented anywhere.
However, this development is not an end game by any means. I have little doubt that the US will come up with ways to circumvent it. What is really troublesome for the military, I suspect, is that it could probably be implimented by 3rd world countries which otherwise don't have the resources for such defense mechanisms.
...I personally feel that stealth is a bad way to play the game. Cheaper unmanned vehicles is far better....fly more, who cares if they shoot a few down....
Lockheed and another company are working on similar products. I believe they are competitors, and the other company took the low budget route, relying on the interference of civilian (AM? FM?) radio stations - a bunch of low tech antennas listening in on the disruptions ("shadows") as planes went around. This was in Aviation Leak several months ago, and I think even hit Slashdot.
Also, apparently the low tech low resolution long wavelength radars still in service by Russia and their customers, who can't afford the snazzy new short wavelength radars in use by NATO, are better at detecting stealth planes than those snazzy new radars. I gather the US tried to downplay this, out of embarrassment and cover-your-ass syndrome.
And another tack is mumble-mumble radar, where the transmitter and receiver are far apart. Stealth planes are stealthy not just from absorbing the radar energy, but also from directing radar energy away from the straight return path. Those non-normal directions get more than their share of the reflection -- put a transmitter ahead of the plane and separate receivers on the side, and the side receivers get a better return from the stealth plane than forward receivers get from a non-stealth plane. Or something like that.
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Infuriate left and right
My take on what the technology actually is.
When watching broadcast TV with a crappy antenna, a plane flying overhead will disrupt the signal. An array ground based antennas can determine the exact pattern of the disruption, and with calibration, determine the size and position of the object causing that disruption. Since the goal isn't to watch TV, the detectors can be made much more sensitive to small disruptions.
The best weather to fly in to avoid this sort of detection would be a thunderstorm (but hard on the planes and pilots).
Such a system is not likely to have the precision of conventional radar, ind is more likely to mistake one target for another (I base that on the longer wavelength of commercial broadcasts).
Final critique, it's a very creative idea!
Infrared radiation and "radiant heat" are the same thing, if that's what you were wondering. (I could go into hand-waving about the characteristics of infrared radiation, but that's not really germaine to the passive Chinese aircraft detection technology or its countermeasures.)
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Time is Nature's way of keeping everything from happening at once... the bitch.
I spent 8 years as a radar tech in the Navy. I can tune a radar in so good that it can detect a seagull at several miles, But it's worthless when it's tuned in that good. Most of the time you can't find the seagull because there's too much Garbage that is also displayed on the screen. So the radar has to be slightly detuned. That way you only see the stronger signals. Stealth takes advantage of this. Tune the radar in good enough to detect the small radar cross section of the plane and you can't find it on the scope because of all the other garbage. Stealth just hides in the garbage. When you consider how much turbulance there is in the air without any plane to add to it you will quickly run into the same problem of finding the target in the garbage.
Quemadmodum gladius neminem occidit, occidentis telum est
Both the F-117 and B-2 fly with special fittings when they are not in combat duty. In the F-117 this is in the form of small rectangular boxes over the wings. These fittings increase the radar cross-section of the airplane and make it equal to an ordinary civilian plane; to make friendly skies safer to fly by allowing the planes to be tracked by air traffic control, just like every other plane.
Plus, you don't want everyone on the fair grounds to learn about the capabilities of the plane. If you're interested in the topic, just compare the cockpit photos of the Mig-29 demonstrated to the West in 1989, and Mig-29s in actual service with the Russian Air Force. You will be amazed to see how they dumbed down the cockpit layout so that the first Western smart-ass to see the photos would say "Gee, Russians are using 1950s technology in these."
It is amazing how this little known security feature causes people to downplay the capabilities of these aircraft. I remember back when a bunch of F-117s came to Turkey; the armed forces and civilian air traffic control boasted how they could easily detect the so-called "stealth" fighters. As the Iraqi and Serbian can tell, it is not that easy without the fittings.
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You're wrong about "go fast." A 747 at max throttle can outpace the stealth aircraft. Going fast generates too much of a heat signature and makes them less stealthy.
Paul
http://www.pauldrobertson.com
An invasion could be undertaken on the US. It would have problems though.
First you send in infiltrators, who set up airstrips in remote locations, and purchase ammunition. They purchase vehicles and fuel. You then take about two dozen chartered commercial jet airlines, you load them with troops and land them at US airports all friendly like, most likely the east coast. It doesnt take long for 500 or so armed troops to capture an airport, and then fortify their position quickly. The 747's can carry anti-tank/heavy weaponary, and plenty of ammunition. No food, cause that isnt neccessary. These troops are the first wave and will only be the front line for a short period. 10-20 minutes behind these 747's, are standard long range cargo planes, carrying light armor vehicles and more troops, these land at the commercial airports and at the private airstrips you have set up.
Your troops take the LAU's and go like hell towards your assigned targets. Airbases, Army Bases, Naval Bases, Police Stations, Gun Stores.
The trick is to move fast and capture quickly. A night attack on a weekend would be best, as you would capture quite afew bases relatively lightly manned and vulnerable, you might even bring pilots/tankers/sailors with you to take the captured vechiles and add to the chaos. You continue to bring in troops from china by air and land them at your secured areas.
At this stage it gets sticky. Your main mode of transport of large armor and troops is by sea. Getting by SOSUS is quite hard, and you have to deal with naval assests in the pacific. Hopefully you would attack at a time when a carrier isnt present close by in the pacific. You have to get your tanks in, so one way would be by using normal car carriers, who are on scheduled runs to make landfall on the same day as your attack to deliver vehicles. If you were serious about your plan, you might even nuke pearl/guam in the first 24 hours of your attack, to make it easier to move more heavy units from china to the US. This would also allow you to move a chinese carrier closer to the US to provide air support for the grunts and eventually transferring all aircraft to captured US runways.
You have to link up your heavy armor, light armor and infantry to push inland, obviously after securing your captured cities. You then utilise these cities, and the railroads to supply food and munitions to your front lines as they spread inland. Time elapsed is about 48-72 hours, more then enough time for the US army to mobilise and to present a good front line, possibly near the rockies.
Attack of the US is not an easy task, and requires exquisite timing of delivery of assets. It requires china to send troops a huge distance, and to get past pearl with ships. It would obviously be easier to attack with an allie close by, say from cuba or south america, to attack other borders at the same time. This draws units away from your main assault.
Now this is a possible scenario, if, china had the logistical assets to do this. The Chinese army is much like the soviet army used to be. A large club to bludgeon your opponent to death with numbers, aslong as he is relatively close. China has never had to move huge amounts of troops over an entire ocean to attack an enemy so far from home. It isnt easy logistically. But possible. To make it more interesting, an enemy may even release chemical/biological weapons before he attacks. He may poison water supplies. He may release anthrax or similar diseases. He may sabotage power stations, he may cause an increase in terrorism before hand.
There are alot of things in warfares bag-o-dirty tricks.
As for disabling the US nuclear counter attack, that is a tough nut to crack, and would require unconventional techniques im sure. For example purchasing properties near known ICBM silos, buying a few hundred stingers and praying you can cripple a few missles before they hit your country. Perhaps small backpack nukes could be used to crack the silos at close range, but thats debatable, as those silos are hardened and quite well built. Maybe wait till they open up to launch? Who knows.
Naval nukes are even harder to disable apart from an intense naval campaign by your forces to kill the subs, even then, they can launch from almost anywhere, and damn but their quiet.
Carrier based nukes are also a concern. It is unlikely you would attack the US without first developing a good ABM defence.
So in answer to your comment
'It would be exceedingly difficult to come anywhere near the US shore with any kind of sizable force.'
True, but not impossible. Give war a chance!:)
Insert something insightful here, or I'll insert something painful there.
From what I've read, if you have a large distributed radar network (many radars all over the place, coordinated by a central computer), you have a high chance of tracking stealth planes like f117 and b2, because one radar's signal will get reflected in a different direction and may be caught by another radar. Also, stealth planes are as visible as ordinary fighters when they open their weapon bays to fire. There have been cases when the weapon bay jams open and then the f117 is basically a sitting duck.
I agree. You'd need to have a good understanding of EM radiation, antenna design etc. Then you'd need some signal processing kit. Due to the amount of EM around, I thing DSP would be daft (in the initial stages of the processing setup at least). I'd look at doing filtering with tuned passive stuff first, then feeding that to some electronics to watch variations, then feed that to an output stage (I'd be doing at a lot of oscilloscope time before I considered digitising it).
I live near a large flock of ravens (corvid family - about 150 of them). They fly over at predictable times at between 30 and 120 feet. I'd calibrate the kit against them first. Calibrating the setup, and keeping it calibrated, would be the headache.
If I could detect the ravens, then I'd ask the US military for a stealth plane to play with. This is where the 'hobbyist' bit is limiting.
I suspect there would be major problems in a populated area with transmissions from electric motors, microwave ovens, mobile phones, overhead lines and all the other bits of electromagnetic technology we rely on. I'd give it a go if I had the time, though.
"the typhoon is huge"
Right. The largest military sub to see active duty.
"it is nuclear powered rather than desal (sp) powered"
Wrong. The Typhoon boats are nuclear, diesel, and battery powered. Why do you think they were so darned big? The reactor put out enough juice for a city. If that failed, there were two mammoth diesel engines. By mammoth, I mean 12'x10'x6', 10,000+ hp, and enough tourque to drive the boat through the water at 20 knots. Should those fail, there were two large banks of dry cell batteries on either bow. The batteries served three purposes:
"I don't think the largest sub in the world is more silent than the water around it."
Wrong. Here's an example: Let's say that there is a skyscraper in the middle of a field (just follow me on this). Now let's say that the wind is blowing out of the North. Let's also say that you are blind, and walking past the south side of the building (going East to West). There will be a point when the building will start to block out the wind. Logic will tell you that it's no longer windy, and it's also very quiet. You may then deduce that there is a building to your right. Here's a diagram:
**********************
**********************
.........--------*****
.........||||||||*****
.........||||||||*****
....o....||||||||*****
.........||||||||*****
.........||||||||*****
.........--------*****
**********************
**********************
Legend:
* = wind;
-,| = building;
o = you;
. = calm air;
Now, relate that to being in a sub. Since there is always ambient noise in the ocean, the trick is to find someplace where there isn't enough noise. That'll be a Typhoon (or maybe a Charlie) with her plant cut way back. If you know where you are and how fast you're going, you can figure a bearing on the Typhoon. Once you have that, you can use basic trig to figure out range, speed, and mark, in that order. After that, it's simple to sneak up and fire your torps and get back out.
zantispam (who gets waaaaaaaay to into this stuff)
Jedi Hacker (Apprentice) and Code Poet
censorship is a form of noise, which actively seeks to drown out content with silence - Crash Culligan
China and the USSR got on bad relations decades ago. I don't think that the "collapse of communism" changed that much.
Even so, you would NOT want to send troops over the Bering strait. Why not? Terrain! Go look at a map, count mountain ranges. That is *not* territory through which you want to maintain an overland supply train.
No, the idea of China invading the US any time soon is sheer idiocy. They are far better advised to just wait. The US today is the largest debtor nation in the world, and it has held that title for over a decade. The current economic boom is hiding it, but eventually the markets will wake up to the fundamental economic reality, and in due course of time military might will follow the money.
The days of the US single-handedly dominating the planet are numbered, and the Chinese leadership knows it. This is not to say that the US will be toothless any time soon. But, like the British Empire before it, the Spanish empire before that, and so on through history, economics is catching up to current World Superpower.
Of course the realization of this status may take a while. Look at the British Empire. Between WW I and WW II the stage was set for its collapse. WW II demonstrated that it would not last, and the years following saw Britain quickly losing its territory. Yet the British public didn't realize this for decades after. They even went to war defending a corner of the Empire as late as the 1980s, and we still have as a last cultural hurrah the James Bond movies...
Cheers,
Ben
My usual seat in the cluetrain is at A HREF="http://pub4.ezboard.com/biwethey.ht
And shortly after this information was leaked, secret double-agent panda Hsing-Hsing committed suicide at the National Zoo. The tricky part was knowing the leak was going to happen months in advance so he could start dying of renal failure.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
In general, everything I've heard, which has been common knowledge in the west, has been that the MiG fighters have a very good reputation for engineering. In particular, westerners seem amazed (I was amazed, for one) to learn that the MiGs are not fly-by-wire and are still very easy to fly.
-- "Ever wonder why the SAME PEOPLE make up ALL the conspiracy theories?"
Honestly, this isn't all that much of a surprise for a number of reasons. The article goes very lightly on Lockheed Martin's Silent Sentry system which we've had for years. So much, in fact, that the way that it works isn't even classified anymore.
Furthermore, it seems that the by using commercial broadcasts you're risking a lot. Turn on your TV with just an antenna. Even use a really powerful antenna. Unless you're right by your local TV station, you're out of luck. The picture will get scrambled from interfereance over space by the uneven random distrubance of everything from atmosphereic/pressure differences to object's in it's path. So unless you had a vaccum and a perfect signal between all your recieving antennas (as has been pointed out you'd need at leat 3 to get a 3D reading, although more would be helpful.), you'll have some interference and turbulance. Furthermore, radio signals in places like China are less likely to be reliable than in more developed countries.
Also remember that we've had this technology for a number of years. We haven't widely deployed it dispite the fact that it's cheaper to do so than most conventional radars. Believe me, the military likes *NEW* toys more than they like *EXPENSIVE* toys. And this would be a new toy. It evedeintly isn't that reliable, unless the Chinese have managed to leapfrog us in this.
Also it's been pointed out that you can just start taking out TV/radio stations. The silence would be deadly if this was your only air defense. You could also theoretically do such things as rotate the plane every now and then to change the way that it disturbs the air. By traveling at different directions to the wind and at different angles and wind patterns, you'll change the turbulance that you create. Also remember that air craft (with the exception of ones like the F-117, designed before we had good enough computers to effectively design a plane like the F-22) are *DESIGNED* to make as little disturbance as possible. Before it was just areodynamics, now it may be a possible way to be stealthy. Futhermore a system this sensative would also detect things such as low pressure zones, air disturbance created by such things as factories, etc. (especially in cities), and would probably be *MUCH* more prevalant than the signature left by a 20m aircraft.
of course the next step is quantum stealth
you can detect it, but as soon as you figure out where it is, you cannot know where its going
Austrailian radar techs discovered they could find stealth aircraft by bouncing radar off the turbulence behind the plane. If you've ever seen an F-117 it has some pretty awesome turbulence, so awesome it needs special compensators just to let the thing fly. Until someone figures out how to build an aircraft with little or no turbulence caused by drag anything is detectable if you put some thought into it.
I'm a loner Dottie, a Rebel.
He said bare essentials. "In a first world sense" presumably includes a number of things one could ( and indeed prior to 1900 would ) live without ( for example, cars and electricity ). You are guilty of confusing "wealth" with "bare essentials"
You then take about two dozen chartered commercial jet airlines, you load them with troops and land them at US airports all friendly like, most likely the east coast. It doesnt take long for 500 or so armed troops to capture an airport, and then fortify their position quickly.500? In most large cities, the police alone would outnumber and outgun them, let alone the national guard.
Your troops take the LAU's and go like hell towards your assigned targets. Airbases, Army Bases, Naval Bases, Police Stations, Gun Stores.
By this time a full scale military alert would already have been triggered, and Beijing would be glowing with the aid of a nearby submarine. Added to which, it would be trivial to block access routes and tie off the groups of troops. Your troops would be stranded, hunted, and eventually crushed with ease most likely by state police units alone, who would once again substantially outnumber and outgun your troops on the ground.
You have one basic flawed premise - the surprise attack. Most likely any hostilities between the two powers would be preceeded by months of posturing, during which time national defenses would be beefed up, airports made more secure, and submarines and bombers would be scouting their targets. Satellites would easily, easily detect any significant movement. Intelligence would likely be able to predict the movement with great accuracy.
I think you've watched Red Dawn too many times.
Why do you need to locate the stealth aircraft at all? Just fly your fighters around the places you don't want bombed, and have them blow up any stealth aircraft that try to attack.
Sending any kind of bomber (which, frankly, the F117A really is) unescorted against fighters has always been suicide. Just because stealth doesn't change that doesn't mean stealth is useless, just that it isn't a shield of invincibility.
Read more: at Lockheed Martin, about Silent Sentry, about a shuttle launch and about information dating back over a year - this all comes very sudden and suprising to the US defense, completely new and previously unknown technology.
© Copyright 1999 Kristian Köhntopp
Power Projection.
Perhaps the Chinese do not have the experience, but the invasion of Taiwan would be a matter of reaching ~80 miles for them, not really a projection, versus reaching ~7000 miles for the US. The Chinese would be able to use ground-based planes and helicopters to cross the strait, and small craft to sail it in a couple of hourse, while the US forces would be limited to carrier-based planes and heavy ships that would take about a week to arrive from San Diego.
People should not fear their government. Governments should fear their people.
Not being a Geography-buff, I don't know the countries... But there's that 7 mile gap between Russia and Alaska... Something "straights". So long as they secured that corridor, they'ed have a very efficient way of moving troops to this side of the Pacific.
;)
Of course, they'ed have to go through Canada prior to getting at us...
Not proportionally, it isn't.
1980: 22.7% of federal budget outlays were Nat'l Defense.
1998: 16.2%.
Deal.
Source: OMB numbers, "Budget of the United States Government". FY 2000 (1999).
Only the dead have seen the end of war.
Not as a percentage of the national budget, which is the only gauge that counts when we are talking about the federal budget.
<laugh> Like I'd trust anything the Clinton News Network has to say about politics.
My journal has hot
>>Now the NRA are an element, but unless you have anti tank weapons, you will have difficulties stopping APC's and medium armor once they emerge from the airport. Not even the US is THAT liberal with weapons:) I work with a few people who wish it were otherwise.
I get the feeling that some of us here have no idea what the NRA is. The NRA is a public policy group like the EFF, they're not a paramilitary organization.
Second, you don't know too much about armament. A 50 caliber rifle can penetrate light and many medium armored vehicles. I would like to save up the 2k needed to buy one, but several people already own them. I would hate to be in an APC while someone is shooting a 50 caliber at it. One lucky shot would fill the inside of that APC with a shower of fast moving HOT metal.
Even 5.56mm Nato is a caliber that has decent ballistics for armor penetration. Especially if you're using the green tip Nato AP rounds.
Even less sohpisticated tanks can be disabled by a 50 caliber round. One shot down the barrel can render a tank's big gun useless. Would you be willing to get out try to use a machinegun against a person whom you can not see who is able to put bullets the size of your thumb into a target the size of an orange?
Also, all it would take is a little fertillizer and diesel fuel and POOF your million dollar tank is on it's back like a beetle, helpless, waiting to get stomped on.
Of all the nations on earth te US would be the hardest nut to crack for an invading army, Switzerland would probably be the only other country in the same league.
Without help from HIGH UP in the US military, such a plan couldn't work. China wouldn't even try. Then again, our current administration helped them get ballistic missile technology, who knows what else is possible.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano