LiberalAtheist
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RCS OF Different Fighters
- Thread starter iceman2009
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Last Hope
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ANTIBODY-
1) MashAllah you have been doing a great job. Never the less, everyone else is
2) Some low life dude has been copying your work from here. Link.
Here is a PDF version, of RCS waves.
http://www.tscm.com/rcs.pdf
1) MashAllah you have been doing a great job. Never the less, everyone else is
2) Some low life dude has been copying your work from here. Link.
Here is a PDF version, of RCS waves.
http://www.tscm.com/rcs.pdf
Manticore
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60% of my threads have been copied [in some cases , alongwith the title of the thread] in the sister forum -- without giving me credits --- apparently spark and other admins have looked the other way.....
DarK-LorD
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Can't be sure.
There have also been reports that the IAF have treated their front line aircraft such as the Jaguar, MiG-29, MiG-27 and Mirage 2000 with a stealth material said to reduce the RCS of aircraft by up to 70% and increases weight by up to 50kg, Aircraft & Aerospace Asia-Pacific, Feb. 1996 pg.20).
http://forum.*********************/lofiversion/index.php/t24522.html
Imran Khan
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you should contact with him directly its not fair man .
SpArK
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Im sorry .. i just logged in again.. i will look into it.
Manticore
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yar , you can open my profile --threads started by me verses the threads started by 'bad wolf' -- half of the threads have been singlehandedly started by him
the thread titles are also somewhat similar
thanks!!
the thread titles are also somewhat similar
thanks!!
Imran Khan
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looking like wolf follow you man keep your gun with you hehehehe
gambit
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A question was asked that since we know that an aircraft's radar cross section (RCS) value can change with aspect angles, with the top/bottom views the greatest, next are the laterals, and front/rear the least, why is the front RCS value always the one presented to the public?
An often given answer is that it is to give as favorable a presentation about the aircraft as possible while remaining technically truthful without sounding too much like sales pitch. On the surface, it sound plausible enough, but given the nature of radar detection, the truth is more complex.
First...We should have a brief review on how radar detection works...
The above illustration is how a flat plate, regardless of dimensions, will offer the receiver side the greatest amount of reflection, or radar observability. That direct reflection is called 'specular reflection' or 'specular energy'. Basic geometry tells us that the angle of deflection is equal to the angle of incident. So as the flat plate is tilted or 'cant' away from perpendicular, the greater the cant angle, the less the amount of reflected energy will be returned to the receiver. The less that amount, the less we have of target resolutions. If the flat plate is so tilted that it is almost horizontal, as how the radar would see it, then we will have statistically insignificant energy. Instead of specular energy, we will have surface wave effects and that is for another discussion.
Because of this behavior...
Receiver B will receive the most amount of specular energy. Lower for Receiver A. And if we have a receiver at the Transmitter location, that receiver will have the lowest amount of specular energy.
Because the aircraft is in constant motion through 3D space, the only time a radar receiver will be looking CONSTANTLY at the aircraft is if it is looking at the nose or tail. Either approaching or receding.
Put this another way, if a radar station is looking at the aircraft's top/bottom or laterals, the aircraft is moving ACROSS the radar's field-of-view and the laws of geometry (reflection) applies. At several hundreds km/h it will not be long before the radar station loses contact. Worse yet for the radar station if the aircraft is purposely designed to have some influences on those reflections via body shaping.
This is the true reason why front/rear aspect RCS values are often presented: That tactically speaking, because of the briefness of such views, top/bottom and lateral RCS values, while very important, they are of lesser tactical significance than front/rear aspects because the radar will be looking CONSTANTLY at those front/rear aspects. Canting the vertical stabs to eliminate corner reflectors reduce further the brevity of lateral aspect viewing.
Now we touch briefly on surface wave behaviors because now the radar impinging signals are either at horizontal or near horizontal to the aircraft's surface...
As the wave travels on the surface, any surface discontinuities such as panel gaps either through manufacturing defects or uncaring maintenance, screw heads, or gouges will send a portion of the wave energy back to the receiver. If enough of these surface discontinuities exists, the radar will have valid target resolutions, even when the front view is usually the least in terms of area presentation.
This is why designers work hard at reducing front/rear aspect RCS, particularly the front because the aircraft will be entering hostile territory.
An often given answer is that it is to give as favorable a presentation about the aircraft as possible while remaining technically truthful without sounding too much like sales pitch. On the surface, it sound plausible enough, but given the nature of radar detection, the truth is more complex.
First...We should have a brief review on how radar detection works...
The above illustration is how a flat plate, regardless of dimensions, will offer the receiver side the greatest amount of reflection, or radar observability. That direct reflection is called 'specular reflection' or 'specular energy'. Basic geometry tells us that the angle of deflection is equal to the angle of incident. So as the flat plate is tilted or 'cant' away from perpendicular, the greater the cant angle, the less the amount of reflected energy will be returned to the receiver. The less that amount, the less we have of target resolutions. If the flat plate is so tilted that it is almost horizontal, as how the radar would see it, then we will have statistically insignificant energy. Instead of specular energy, we will have surface wave effects and that is for another discussion.
Because of this behavior...
Receiver B will receive the most amount of specular energy. Lower for Receiver A. And if we have a receiver at the Transmitter location, that receiver will have the lowest amount of specular energy.
Because the aircraft is in constant motion through 3D space, the only time a radar receiver will be looking CONSTANTLY at the aircraft is if it is looking at the nose or tail. Either approaching or receding.
Put this another way, if a radar station is looking at the aircraft's top/bottom or laterals, the aircraft is moving ACROSS the radar's field-of-view and the laws of geometry (reflection) applies. At several hundreds km/h it will not be long before the radar station loses contact. Worse yet for the radar station if the aircraft is purposely designed to have some influences on those reflections via body shaping.
This is the true reason why front/rear aspect RCS values are often presented: That tactically speaking, because of the briefness of such views, top/bottom and lateral RCS values, while very important, they are of lesser tactical significance than front/rear aspects because the radar will be looking CONSTANTLY at those front/rear aspects. Canting the vertical stabs to eliminate corner reflectors reduce further the brevity of lateral aspect viewing.
Now we touch briefly on surface wave behaviors because now the radar impinging signals are either at horizontal or near horizontal to the aircraft's surface...
As the wave travels on the surface, any surface discontinuities such as panel gaps either through manufacturing defects or uncaring maintenance, screw heads, or gouges will send a portion of the wave energy back to the receiver. If enough of these surface discontinuities exists, the radar will have valid target resolutions, even when the front view is usually the least in terms of area presentation.
This is why designers work hard at reducing front/rear aspect RCS, particularly the front because the aircraft will be entering hostile territory.
gambit
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A question was asked about a comment I made elsewhere that radar cross section (RCS) is essentially a 'fictitious' value.
fic·ti·tious/fikˈtiSHəs/Adjective
1. Not real or true, being imaginary or having been fabricated.
2. Of, relating to, or denoting the imaginary characters and events found in fiction.
Especially when there are mathematical figures presented for various aircrafts.
The context of the word 'fictitious' here mean the value depends on HOW an object present itself to the observer.
I will use a classroom example from long ago...
We declare that a 'hand' consist of four 'fingers' and one 'thumb'. But the question now become do we make that declaration a priori or do we make that declaration only after we actually see the objected meeting all criteria.
Take your hand with all elements group tightly into a knife like form. Now look at it from its edge. You will see the element called the 'thumb' as dominant and barely the other elements. If you insist that you must see all elements of the object 'hand' before you will admit that the thing you are seeing is a 'hand', then you are not looking at a 'hand' but an unknown object. As you rotate this object, you will eventually see all elements. At this point, if you insist that you must see all elements distinctly apart from each other before you can declare you are looking at a 'hand', then you must admit you are looking at an unknown object.
The reason you may consider this exercise absurd is because you already determined what a 'hand' look like regardless of its formation and as long as you see enough physical characteristics of a 'hand', even though you do not see all, you declare for yourself that you have seen enough well established physical traits to declare that you are looking at a 'hand'.
This is how an RCS can be a fictitious value but can still have a mathematical representation. An aircraft in flight is a dynamic target. Sometimes it will present to the seeking radar its full straight on aspect with the highest electrical return. Sometimes not. An aircraft is an unnatural phenomenon. We built it so we know its electrical characteristics. We program the radar to discard certain things we know and enhance certain other things as long as these things present themselves to us views that meet minimum electrical characteristics.
fic·ti·tious/fikˈtiSHəs/Adjective
1. Not real or true, being imaginary or having been fabricated.
2. Of, relating to, or denoting the imaginary characters and events found in fiction.
Especially when there are mathematical figures presented for various aircrafts.
The context of the word 'fictitious' here mean the value depends on HOW an object present itself to the observer.
I will use a classroom example from long ago...
We declare that a 'hand' consist of four 'fingers' and one 'thumb'. But the question now become do we make that declaration a priori or do we make that declaration only after we actually see the objected meeting all criteria.
Take your hand with all elements group tightly into a knife like form. Now look at it from its edge. You will see the element called the 'thumb' as dominant and barely the other elements. If you insist that you must see all elements of the object 'hand' before you will admit that the thing you are seeing is a 'hand', then you are not looking at a 'hand' but an unknown object. As you rotate this object, you will eventually see all elements. At this point, if you insist that you must see all elements distinctly apart from each other before you can declare you are looking at a 'hand', then you must admit you are looking at an unknown object.
The reason you may consider this exercise absurd is because you already determined what a 'hand' look like regardless of its formation and as long as you see enough physical characteristics of a 'hand', even though you do not see all, you declare for yourself that you have seen enough well established physical traits to declare that you are looking at a 'hand'.
This is how an RCS can be a fictitious value but can still have a mathematical representation. An aircraft in flight is a dynamic target. Sometimes it will present to the seeking radar its full straight on aspect with the highest electrical return. Sometimes not. An aircraft is an unnatural phenomenon. We built it so we know its electrical characteristics. We program the radar to discard certain things we know and enhance certain other things as long as these things present themselves to us views that meet minimum electrical characteristics.
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