Radar

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posted on Apr, 23 2005 @ 01:02 PM
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- We've got "low frequency" radars which operate under 2Ghz and can detect everything as it is believed. That must mean that it can also detect X-planes, the new F-22, B-2 ect ect.
but it can only pinpoint the aircraft within 30-50m (or feet).
So basicly its useless for shooting it down!

- Then there is "Tamara" which can detect a stealth plane's "e-missions" and thereby trace it and shoot it down like in Kosovo.
But pilots are well common with the term "radio silence" while in combat, so it useless too.

- The UK has a radar system that can detect a stealth plane, according to them (I don't know the name), but can they shoot it down as well??

- Unknown...



Is this correct? I'm sure there is more to it, can anyone help me out, again?

Intergurl where you at?




posted on Apr, 23 2005 @ 06:24 PM
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There are many, many, "low frequency" radars that operate under 2GHz. They cannot detect everything, in fact just the opposite is true.

Radar energy is RF waves. The wavelength of an RF wave is inversely proportional to it's frequency. That means a lower frequency radar will have a longer wavelength and a high frequency radar will have a short wavelength.

For a radar to detect a target it needs 1/4 of the wavelength to be returned. Therefore, the higher the frequency of the radar, the smaller the object it is capable of detecting. If two aircraft are flying extremely close together, a low frequency radar, with a long wavelength, will show them as only one target. A high frequency radar will be able to discriminate between the two and display them as two seperate targets. The US Phallanx CIWS system has a very high frequency radar. It fires 20mm rounds and because of it's high frequency radar, it tracks each bullet it fires so it can adjust it's aim. It is said the SPY-1 radar on the Aegis ships can detect a basketball sized object at 250 miles.

A low frequency radar has a longer wavelength so it can only detect larger targets, relatively speaking. This isn't good for detecting stealth aircraft, which have a very small radar cross section.

You are right that there is a difference between detecting a target and being able to fire on it. Fire control radars need to be much more accurate and determine a lot more information about a target than a simple search radar does. That's why for years there were seperate search and firecontrol radars. In the movies, when a pilot gets a 'tone' and knows he's being tracked, it's because a fire control radar was tracking him. Modern radars perform both search and track functions, so a pilot never knows he has been fired on until the missile activates it's radar seeker (if it's a radar guided missile) and by then it's too late to do anything.

There are several ways to detect stealth aircraft, but they are extremely difficult to incorporate into a radar. An extremely high frequency radar would be able to pick up very small targets, like the seams of the aircraft, any lips around the cockpit, etc. However, a radar this sensitive would also be tracking things like grass blowing in the wind, insects, etc. Another way to find stealth aircraft is too look for a 'hole' in the radar returns. There is a very slight amount of the radar's energy that is returned from normal atmospheric conditions. Looking for a hole means looking for a small area where there is absolutely no return at all, like a 'hole' in the sky. Needless to say, building a receiver this sensitive is extremely difficult. I believe this was recognized by the designers of the F-117, B-2, and F-22 and they were designed to return a small amount of radar so they wouldn't be detected by these means.

When you say "e-missions" I'm assuming you mean electronic emmissions from the aircraft, like comms or active radars. There is a whole seperate area of sensors that search for radar and comm emmissions. They can give a bearing to a target, but cannot provide enough data to track or fire on a target.

A stealth aircraft holds it's weapons internal. When it is ready to fire it opens weapon bay doors to release the weapons. The bay doors reflect radar and the plane is detectable when it is firing. I was under the impression that this is how the F-117 in Kosovo got shot down.



posted on Apr, 23 2005 @ 06:29 PM
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- The UK has a radar system that can detect a stealth plane, according to them (I don't know the name), but can they shoot it down as well??


RADAR, not so sure, but the UK's Rapier SAM system is quite capable of tracking, targetting and shooting down stealth aircraft.

This is due to it having IR as we as RADAR.



The Dagger target acquisition and surveillance radar is a multi-beam high resolution 3D radar supplied by Alenia Marconi Systems. The radar is a frequency agile 3D pulse Doppler radar operating in J-band, with scan rate of 60 or 30rpm. The maximum detection range of the radar is in excess of 15km. An optional range of 32km is available. The maximum elevation is 5km. The system has the processing capacity to detect more than 75 threats per second. The radar provides bearing data and threat assessment from a Cossor Mark 10 or 12 IFF (Identification Friend or Foe) system. The signal processing system incorporates clutter rejection algorithms and is also resistant to electronic countermeasures. A high elevation guard beam automatically switches off the transmissions when the presence of an anti-radiation missile is detected.

The Blindfire tracking radar, supplied by Alenia Marconi Systems, is a differential monopulse frequency agile radar operating at F-band which provides fully automatic all-weather engagement to a range of 15km. The output is sufficiently powerful to burn through most jamming signals and the radar uses advanced frequency management techniques to evade jamming and other hostile electronic countermeasures. The system incorporates a self-surveillance reversionary mode of operation. A dedicated missile command link provides dual firing capability.

The electro-optic tracking device, a passive infra-red electro-optic sensor, is mounted on the top of the turret in a spherical housing and is controlled by an operator at a weapon control terminal. The tracking device can be used in scanning mode to provide passive target detection and acquisition in radar-silent operations. Raytheon Systems Limited has been awarded a contract to supply all the UK Army’s Rapier FSC systems with the SIFF (Successor Identification Friend or Foe).





Rapier

Have a read


[edit on 23/4/05 by stumason]



posted on Apr, 23 2005 @ 08:33 PM
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Your quote says that this radar has a range of up to 32Km that's only 20miles? It cant detect stealth aircraft past 20miles? And what range of RCS can the Rapier detect?



posted on Apr, 23 2005 @ 08:57 PM
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Your quote says that this radar has a range of up to 32Km that's only 20miles?


Bear in mind Westy that this is a battlefield system, and further range is not required. However, it can be intergrated into a wider Air defense system if needed, as it only uses the onboard tracking systems for target acquisition and firing, which takes all of 5 seconds.

If the wider Air defense network picks up an incoming target, then this info can be relayed to the relevant AA battery, and the Rapier can be fired as soon as the target enters range.

20 miles is plenty far enough if the plane doesn't know your there. And with the missile doing Mach 2.5+, the chances are they won't know whats coming until it's to late.

I can't seem to find any info on the cross section capabilities, but that isn't surprising, as this is the latest variant and therefore classified I would assume.

And Westy, I detect from your post there that somehow this is going to degenerate into a "Well, the US is kick-arse number one, can't shoot us down, woooo-yeah!" thread?

Why the put down?

If you really want to know, the F-117 can be easily tracked and targetted by the Rapier and this was done without the F-117 pilot knowing.

It caused quite a stink in 1996 (I think it was) when this was leaked to the news, and the Americans were not best pleased that it was announced on the BBC! (and that wasn't the latest version either)






[edit on 23/4/05 by stumason]



posted on Apr, 23 2005 @ 11:28 PM
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Nope I have no intention of going to a U.S. Vs. whoever topic. I was just surprised at the range that's all. I’m sure this system will do well against most aircraft the Brits and the U.S. will faced, I am just interested on what its capabilities are against Stealth planes.



posted on Apr, 23 2005 @ 11:50 PM
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Originally posted by stumason


Your quote says that this radar has a range of up to 32Km that's only 20miles?


Bear in mind Westy that this is a battlefield system, and further range is not required. However, it can be intergrated into a wider Air defense system if needed, as it only uses the onboard tracking systems for target acquisition and firing, which takes all of 5 seconds.

If the wider Air defense network picks up an incoming target, then this info can be relayed to the relevant AA battery, and the Rapier can be fired as soon as the target enters range.

20 miles is plenty far enough if the plane doesn't know your there. And with the missile doing Mach 2.5+, the chances are they won't know whats coming until it's to late.

I can't seem to find any info on the cross section capabilities, but that isn't surprising, as this is the latest variant and therefore classified I would assume.

And Westy, I detect from your post there that somehow this is going to degenerate into a "Well, the US is kick-arse number one, can't shoot us down, woooo-yeah!" thread?

Why the put down?

If you really want to know, the F-117 can be easily tracked and targetted by the Rapier and this was done without the F-117 pilot knowing.

It caused quite a stink in 1996 (I think it was) when this was leaked to the news, and the Americans were not best pleased that it was announced on the BBC! (and that wasn't the latest version either)






[edit on 23/4/05 by stumason]


Well, not meaning to turn this into a pi**ing contest, but that is completely false. If you really think that a stealth aircraft can be "easily" tracked by any system out there, you really have no clue as to what you are talking about. I've heard the same arguments before in reference to that F-117 incident, and there are a LOT more details to it. I've seen it before on multiple forums, someone steps in saying, "Oh, the F-117 can be easily tracked by yada yada.....stealth aircraft aren't that stealthy yada yada" and they haven't a clue as to what they're saying, and no one really does until an actual engineer of some type steps in and explains some things.

"Stealth" is a very complicated subject, one most people don't understand. Unless you've got a Phd in the subject of stealth aircraft, you really shouldn't say such a thing. You cannot "easily" track a stealth aircraft. There are two factors that are common sense even that should tell you that. One, the U.S. continues to pour plenty of money into it, and they are NOT going to pour money into something that doesn't work, two, the MEDIA? Man, never believe a word of the media, ESPECIALLY the BBC of all the media outlets. They exaggerate information and NEVER have a clue as to what they are talking about. The BBC, the New York Times, etc...NEVER believe a word they say. They are incredibly biased as well.

You are going to seriously take the words of JOURNALISTS on something as complicated as stealth aircraft?

And no, this is not a "U.S. military equipment is unbeatable, undetectable, yada yada" type post, it is a, "Stealth aircraft cannot be "easily tracked" and anyone who says so doesn't know what they're saying post." Yes, stealth aircraft can be detected, but it is very difficult. Like I said, it is a complicated subject that really none of us are qualified to discuss.

There are a LOT of factors involved. As for the F-117 being shot down, heck, the pilots had flown that route multiple times already even. I am NOT saying the F-117 wasn't or isn't detectable, but to say it can be "easily detected and tracked" is, well, pure and utter ignorance.

A good deal of stealth technical knowledge is classified even, as the U.S. military doesn't want other countries getting access to technology they have a monopoly on.



posted on Apr, 24 2005 @ 05:21 AM
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There are many, many, "low frequency" radars that operate under 2GHz. They cannot detect everything, in fact just the opposite is true.


Fine, dont believe what anyone in here says but would you believe a US Navy pilot??



"nothing invisible in the radar frequency range below 2GHz" [reverse translation from Russian] and with a well-designed low-frequency radar it is possible to "see even a dragonfly at a great distance" [reverse translation from Russian].


But, can the UK rapior detect a stealth plane or not?

Btw doens't Russia or China have anything that can detect those stealth planes?? (maybe they should also start doing bussiness with alliens
)

[edit on 24-4-2005 by 187onu]



posted on Apr, 24 2005 @ 05:28 AM
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What about the "Tamara" system?



posted on Apr, 24 2005 @ 07:38 AM
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Btw doens't Russia or China have anything that can detect those stealth planes?? (maybe they should also start doing bussiness with alliens.


The Russians always hype their stuff up and say they have some thing new to detect stealth planes BS. Maybe they have good radar but I don't think they can detect the B-2 or the F/A-22 yet. Don't know about China but since they get most of their stuff from Russia I don't think they have anything.


Fine, dont believe what anyone in here says but would you believe a US Navy pilot??


USN pilot??? You quoted a Russian guy or what?



posted on Apr, 24 2005 @ 07:42 AM
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My guess is that the Russians CAN detect the planes, but launching a SAM at them or firing AAA at a B-2 or F-117 is a totally different thing, I don't see B-2s getting shot down for another 20 years at least.



posted on Apr, 24 2005 @ 08:21 AM
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A big part of the success of stealth is the flightpath the aircraft take. They do their best to skirt around the air defences. At close range the stealth aircraft are detectable and they fly their missions to stay out of that range. They zig-zag all over a countries airspace to get to a target instead of flying in a straight line. That's a fact most people leave out when they discuss stealth technology.

Submarines can be detected with MAD (Magnetic Anomoly Detector). When you have a large chunk of metal the earth's magnetic field is effected by it, and a MAD sensor detects the flucuations in the Earth's magnetic field caused by the presence of the sub. I'm sure this technology could be used to create a sensor to detect metal in the air as well, it would just have to be much more sensitive.



posted on Apr, 24 2005 @ 09:32 AM
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that still doens't answere mu last question though.
yea I know about the path's it has to take in order to aviod being detected, but still, lets say yo increase the radar range, you'll also increase the RCS.



posted on Apr, 24 2005 @ 09:57 AM
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The RCS is the size that an object appears to be on a radar display. It's said the B-2 has the RCS of an object the size of a bumble bee. That's why it's hard to detect. The RCS and range of a radar aren't related since one is the property of an object and the second is the property of a radar system.



posted on Apr, 24 2005 @ 02:02 PM
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posted by Broadsword20068
you really have no clue as to what you are talking about.


Haha....I really think I do.



posted by Broadsword20068
"Oh, the F-117 can be easily tracked by yada yada.....stealth aircraft aren't that stealthy yada yada" and they haven't a clue as to what they're saying, and no one really does until an actual engineer of some type steps in and explains some things


Well....I have had an "actual" engineer step in and explain things. I have spoken to many Army techs (including my own father) that know this system inside out.

As stated above, Stealth isn't about being totally invisible to RADAR, but your ability to avoid it where possible and where not, to make yourself as inconspicuos as possible. There are radar out there that can track insects, let alone the RCS of a B2 or an F-117, but there use in an actual. working AA system is questionable.

If you had bothered to read the information I posted about Rapier (which you never do Broadsword, you pipe up with the "Big I Am" every time) then you will see that it has two seperate types of RADAR as well as an IR optical tracking system.



When the surveillance radar detects and acquires a target, the bearing data is downloaded to the tracking radar and the launcher, which then automatically align to the target bearing. The target is acquired on the optical tracking system. When the surveillance radar has confirmed that the target is hostile the missile is launched. The missile is guided towards the target at speed in excess of Mach 2.5 by passive infra-red line of sight and active command to radar line of sight.


This means that as long as the battery is given a heading and bearing for the incoming target, it can be guided home using an IR optical system (which is passive). The missile will hurtle towards it's target at Mach 2.5 without the pilot even being aware until it is too late.


posted by Broadsword20068
You are going to seriously take the words of JOURNALISTS on something as complicated as stealth aircraft?


Nope. I will, however, take the word of Army and RAF engineers and pilots. My family is chocka-block full of them.


posted by Broadsword20068
I am NOT saying the F-117 wasn't or isn't detectable, but to say it can be "easily detected and tracked" is, well, pure and utter ignorance.


There is a difference between being able tio track a target and actually use that data to target it. Go back and see the principles on how stealth works.

Yes, the planes have a lovely, low RCS, but that does not mean they are invisible by a long shot, you just need a higher frequency RADAR to see them.

There are RADARs out there that can pick up the seams on an aircrafts frame or the ridges in the canopy. There use in an AA system is still questionable, but they most certainly can detect "Stealth" aircraft, should one stray near. That is the limit on the High Frequency RADAR, the range. But I wont confuse you here with a discussion about that



posted on Apr, 24 2005 @ 02:18 PM
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The high frequency radars like Rapier are nearly useless for detection , because they have very limited range. Thats the reason why they are using only for high precision short range targeting. 15km? LOL REGULAR radar can detect F-22 at such range you don't need the high frequency one!
The stealth is not invisibilty (that's the reason planes are called stealthy not invisible) - it's all about the shorter detection ranges. Yes some radars can detect F-22 or even B-2 but the stealth plane can find "gaps" between them or simply destroy them.
It will not help you if you can detect F-22 at 15-20km because if you detect it it's very likely you have already HARM over your head!

BTW I searched on the Google on stealth topic and some site stated that F-22 can be detected at 420-45km by some very advanced ground radars (likely those huge anti balistic misilles monsters) and at 20 km by the todays most advanced aircraft radars (probably AWACS? or figther radars like Mig-31 and F-14). However they stated the B-2 is hard to detect at all.



posted on Apr, 24 2005 @ 02:24 PM
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Originally posted by 187onu
- We've got "low frequency" radars which operate under 2Ghz and can detect everything as it is believed. That must mean that it can also detect X-planes, the new F-22, B-2 ect ect.
but it can only pinpoint the aircraft within 30-50m (or feet).
So basicly its useless for shooting it down!


I don't think it would be useless. Let's say you have such radar and misille with active radar seeker like Amraam. You don't need to know the accurate position, you can just guide the misille to the approximate position where the misille own radar starts the work. And be sure that no todays plane can be stealth if advanced misille radar is lets say 1km away.
According to NATO gen. Wesley Clark it's possible this was the "solution" to shot down the F-117 over Kosovo (together with the flight path and time info) - older soviet misilles modified to work on longer waves.

[edit on 24-4-2005 by longbow]



posted on Apr, 24 2005 @ 02:28 PM
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The high frequency radars like Rapier are nearly useless for detection , because they have very limited range. Thats the reason why they are using only for high precision short range targeting.


Thats what I said above
. A fixed installation, high frequency RADAR is liekly to pass that bearing info through to the Rapier Battery, who will take care of the business side of things.



It will not help you if you can detect F-22 at 15-20km because if you detect it it's very likely you have already HARM over your head!


Thats where this comes in:



A high elevation guard beam automatically switches off the transmissions when the presence of an anti-radiation missile is detected.


Although not foolproof, if the Rapier is not required for tracking purposes, you don't need the Radar on it turned on all the time anyway.



posted on Apr, 24 2005 @ 02:43 PM
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Originally posted by stumason
A high elevation guard beam automatically switches off the transmissions when the presence of an anti-radiation missile is detected.



I wonder how will this work against future anti radiation misilles like AARGM - they have also active milimeterwave radar to seek for vehicles and other radar platforms if they shut down their own radar.


[edit on 24-4-2005 by longbow]



posted on Apr, 24 2005 @ 02:51 PM
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I wonder how will this work against future anti radiation misilles like AARGM - they have also active milimeterwave radar to seek for vehicles and other radar platforms if they shut down their own radar


Dunno if it would work, but it popped into my head. Stick your SAM behind a large metal screen, with enough room to track and fire yourself. With any luck...the AARGM might lock onto the screen, thinking its the SAM, whislt the SAM can scuttle off....just a thought!





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