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PAF's Electronic Warfare F-16 Falcon

So does this mean PAF moving away reliance from its dedicated Falcon 20 EW platform.

Pakistan_Air_Force_No_24_Blinders_Squadron_Falcon_DA-20_left_side1.jpg
 
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Apparently the gold tint was also applied on the Growler's canopy, again the author gives a different reason.

''EA-6Bs have this is well - it shields the cockpit and crew from radiation. Gold is a very dense material with high conductivity, so even an extremely thin layer (so you can see through it) would already be effective. The gold coating would create a "Faraday cage" effect.

On an EA-6B this was very useful since this aircraft could carry up to 5 jamming pods which emitted an enormous amount of energy in the form of radiation.''


prowler-5-960x720.jpg
 
.
Apparently the gold tint was also applied on the Growler's canopy, again the author gives a different reason.

''EA-6Bs have this is well - it shields the cockpit and crew from radiation. Gold is a very dense material with high conductivity, so even an extremely thin layer (so you can see through it) would already be effective. The gold coating would create a "Faraday cage" effect.

On an EA-6B this was very useful since this aircraft could carry up to 5 jamming pods which emitted an enormous amount of energy in the form of radiation.''

prowler-5-960x720.jpg
Thanks brother, almost posted that earlier.

Probably apocryphal but I read that airmen sitting in the two Electronic Warfare crew stations in the back cockpit had their ----s fried (lost fertility presumably) before the gold tints were developed.

But regarding current aircraft, gambit is very correct.
 
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I am an absolute layman on the topic so kindly excuse me if this sounds stupid, but couldn't it be possible that this coating be serving both purposes like reducing RCS and also not allowing harmful radiation inside the cockpit?

Also, I was wondering when jamming is being performed by a fighter ... what is the state of performance of its own radar? Would it still be able to provide launching information about the target to it's radar guided bvraams? There must be a lot of interference from the jamming waves being sent from the jamming pod / emitters?

@Naif al Hilali @gambit @Windjammer @messiach
 
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.
I am an absolute layman on the topic so kindly excuse me if this sounds stupid, but couldn't it be possible that this coating be serving both purposes like reducing RCS and also not allowing harmful radiation inside the cockpit?

Also, I was wondering when jamming is being performed by a fighter ... what is the state of performance of its own radar? Would it still be able to provide launching information about the target to it's radar guided bvraams? There must be a lot of interference from the jamming waves being sent from the jamming pod / emitters?

@Naif al Hilali @gambit @Windjammer @messiach
My guess is that if jamming is being performed, radar can't be perfectly used for tracking and targeting. Rough guess based BMD ship targeting ballistics missile is venerable to anti ship missiles or subs launched weapon as most of internal power is concentrated on one object. That is personal guess. Might be wrong.
 
. . .
Hello,

Although the forum heavyweights have answered in detail, I would try and write a dumbed down version of the technical details.

The gold film can (not saying why it might appear on some aircraft vs the some others or not) serve both purposes, RCS reduction and EM protection.

It might help some to realise that the "Radiation" others have mentioned is essentially comprised of EM waves. The visible light rays are also the same EM waves in their nature (just at a different set of frequencies/wavelengths). So, just like a gold tint makes the canopy partially opaque visually (not too much since you do not want pilot's view of the outside to get blocked), the tint makes the canopy partially opaque to external EW waves as well. Now the degree of opaqueness will be different from what we can see visually (visible spectrum of EM waves) depending upon the frequency of the radar.

As such, for the radar waves coming from the outside, the canopy will be somewhat like an extension of the skin of the aircraft and would not present a sharp gradient/edge. Since the canopy will be reflecting the radar waves instead of the equipment inside the cockpit. This could in theory reduce the radar spikes that were explained earlier in the thread. Hence the RCS reduction.

SImilarly, the EM waves emitted by the jammers/ECM equipment from outside the cockpit will not penetrate much into the cockpit. Essentially they will not exceed the permissible levels.

As pointed out above, any conductive material could be used to in the canopy to get this effect, it does not need to translucent/opaque in the visible light domain.
 
.
Amazing how first scientific apparatus to detect the nucleus was also of Gold (To converge) rays somewhere in the early 20th Century.
 
.
simple test to see rf ... if u have a radio transmitter around 4w output carrier - take a flourescent tube light next to it; it will start to flicker.

i have had rf burns; when you are setting up field antenna and some idiot decides to test the antenna while some one is hold the hf antenna wire at end, you land up with rf burns; with radar that is much much higher frequency and that can be lethal.
 
.
All F-16s as far as I know have gold tinted canopy. The rear fixed part is clear.

The gold tint protects from any radiation including the sun.

The intense gold tint in the picture looks more like a photoshopped image.
 
. .
"Radar jamming and deception
From Wikipedia, the free encyclopedia

Radar jamming and deception (electronic countermeasures) is the intentional emission of radio frequency signals to interfere with the operation of a radar by saturating its receiver with noise or false information. There are two types of radar jamming: Mechanical and Electronic jamming.

Contents
Mechanical jamming
Mechanical jamming is caused by devices which reflect or re-reflect radar energy back to the radar to produce false target returns on the operator's scope. Mechanical jamming devices include chaff, corner reflectors, and decoys.

  • Chaff is made of different length metallic strips, which reflect different frequencies, so as to create a large area of false returns in which a real contact would be difficult to detect. Modern chaff is usually aluminum coated glass fibers of various lengths. Their extremely low weight and small size allows them to form a dense, long lasting cloud of interference.
  • Corner reflectors have the same effect as chaff but are physically very different. Corner reflectors are many-sided objects that re-radiate radar energy mostly back toward its source. An aircraft cannot carry as many corner reflectors as it can chaff.
  • Decoys are maneuverable flying objects that are intended to deceive a radar operator into believing that they are actually aircraft. They are especially dangerous because they can clutter up a radar with false targets making it easier for an attacker to get within weapons range and neutralize the radar. Corner reflectors can be fitted on decoys to make them appear larger than they are, thus furthering the illusion that a decoy is an actual aircraft. Some decoys have the capability to perform electronic jamming or drop chaff. Decoys also have a deliberately sacrificial purpose i.e. defenders may fire guided missiles at the decoys, thereby depleting limited stocks of expensive weaponry which might otherwise have been used against genuine targets.
Electronic jamming


German Luftwaffe Tornado ECR.
Electronic jamming is a form of electronic warfare where jammers radiate interfering signals toward an enemy's radar, blocking the receiver with highly concentrated energy signals. The two main technique styles are noise techniques and repeater techniques. The three types of noise jamming are spot, sweep, and barrage.

  • Spot jamming occurs when a jammer focuses all of its power on a single frequency. While this would severely degrade the ability to track on the jammed frequency, a frequency-agile radar would hardly be affected because the jammer can only jam one frequency. While multiple jammers could possibly jam a range of frequencies, this would consume a great deal of resources to have any effect on a frequency-agile radar, and would probably still be ineffective.
  • Sweep jamming is when a jammer's full power is shifted from one frequency to another. While this has the advantage of being able to jam multiple frequencies in quick succession, it does not affect them all at the same time, and thus limits the effectiveness of this type of jamming. Although, depending on the error checking in the device(s) this can render a wide range of devices effectively useless.
  • Barrage jamming is the jamming of multiple frequencies at once by a single jammer. The advantage is that multiple frequencies can be jammed simultaneously; however, the jamming effect can be limited because this requires the jammer to spread its full power between these frequencies, as the number of frequencies covered increases the less effectively each is jammed.
  • Base jamming is a new type of Barrage Jamming where one radar is jammed effectively at its source at all frequencies. However, all other radars continue working normally.
  • Pulse jamming produces noise pulses with period depending on radar mast rotation speed thus creating blocked sectors from directions other than the jammer, making it harder to discover the jammer location.
  • Cover pulse jamming creates a short noise pulse when radar signal is received thus concealing any aircraft flying behind the EW craft with a block of noise.
  • Digital radio frequency memory, or DRFM jamming, or Repeater jamming is a repeater technique that manipulates received radar energy and retransmits it to change the return the radar sees. This technique can change the range the radar detects by changing the delay in transmission of pulses, the velocity the radar detects by changing the doppler shift of the transmitted signal, or the angle to the plane by using AM techniques to transmit into the sidelobes of the radar. Electronics, radio equipment, and antenna can cause DRFM jamming causing false targets, the signal must be timed after the received radar signal. By analysing received signal strength from side and backlobes and thus getting radar antennae radiation pattern, false targets can be created to directions other than one where the jammer is coming from. If each radar pulse is uniquely coded it is not possible to create targets in directions other than the direction of the jammer
  • Deceptive jamming uses techniques like "range gate pull-off" to break a radar lock.[1][2]
Inadvertent jamming
In some cases, jamming of either type may be caused by friendly sources. Inadvertent mechanical jamming is fairly common because it is indiscriminate and will affect any nearby radars, hostile or not. Electronic jamming can also be inadvertently caused by friendly sources, usually powerful EW platforms operating within range of the affected radar. Unintentional electronic jamming is most easily prevented by good planning and common sense, though sometimes it is unavoidable.

Countermeasures
  • Blip enhancement
  • Constantly alternating the frequency that the radar operates on (frequency hopping) over a spread-spectrum will limit the effectiveness of most jamming, making it easier to read through it. Modern jammers can track a predictable frequency change, so the more random the frequency change, the more likely it is to counter the jammer.
  • Cloaking the outgoing signal with random noise makes it more difficult for a jammer to figure out the frequency that a radar is operating on.
  • Limiting unsecure radio communication concerning the jamming and its effectiveness is also important. The jammer could be listening, and if they know that a certain technique is effective, they could direct more jamming assets to employ this method.
  • The most important method to counter radar jammers is operator training. Any system can be fooled with a jamming signal but a properly trained operator pays attention to the raw video signal and can detect abnormal patterns on the radar screen.
  • The best indicator of jamming effectiveness to the jammer is countermeasures taken by the operator. The jammer does not know if their jamming is effective before operator starts changing radar transmission settings.
  • Using EW countermeasures will give away radar capabilities thus on peacetime operations most military radars are used on fixed frequencies, at minimal power levels and with blocked Tx sectors toward possible listeners (country borders)
  • Mobile fire control radars are usually kept passive when military operations are not ongoing to keep radar locations secret
  • Active electronically scanned array (AESA) radars are innately harder to jam and can operate in Low Probability of Intercept (LPI) modes to reduce the chance that the radar is detected.
  • A quantum radar system would automatically detect attempts at deceptive jamming, which might otherwise go unnoticed.[3]

Stealth
Stealth technologies like radar-absorbent materials can be used to reduce the return of a target.

Interference
While not usually caused by the enemy, interference can greatly impede the ability of an operator to track. Interference occurs when two radars in relatively close proximity (how close they need to be depends on the power of the radars) are operating on the same frequency. This will cause "running rabbits", a visual phenomenon that can severely clutter up a scope with useless data. Interference is not that common between ground radars, however, because they are not usually placed close enough together. It is more likely that some sort of airborne radar system is inadvertently causing the interference—especially when two or more countries are involved.

The interference between airborne radars referred to above can sometimes (usually) be eliminated by frequency-shifting the magnetron.

The other interference often experienced is between the aircraft's own electronic transmitters, i.e. transponders, being picked up by own radar. This interference is eliminated by suppressing the radar's reception for the duration of the transponder's transmission. Instead of "bright-light" rabbits across the display, one would observe very small black dots. Because the external radar causing the transponder to respond is generally not synchronised with your own radar (i.e. different PRFs [pulse repetition frequency]), these black dots appear randomly across the display and the operator sees through and around them. The returning image may be much larger than the "dot" or "hole", as it has become known, anyway. Keeping the transponder's pulse widths very narrow and mode of operation (single pulse rather than multi-pulse) becomes a crucial factor.

The external radar could, in theory, come from an aircraft flying alongside your own, or from space. Another factor often overlooked is to reduce the sensitivity of one's own transponder to external radars; i.e., ensure that the transponder's threshold is high. In this way it will only respond to nearby radars—which, after all, should be friendly.

One should also reduce the power output of the transponder in like manner.

Jamming police radar
Jamming radar for the purpose of defeating police radar guns is simpler than military-grade radar jamming.[4]

Jamming in nature
The jamming of bat sonar by certain tiger moth species has recently been confirmed.[5] This can be seen as nature's equivalent of radar jamming."

All F-16s as far as I know have gold tinted canopy. The rear fixed part is clear.

The gold tint protects from any radiation including the sun.

The intense gold tint in the picture looks more like a photoshopped image.
No

i may ask simple question sir ?
why they use golden canopy ?
---------------

Short Simplified Answer:

Primarily to reduce radar reflections from inside the cockpit so that they fall to a level more consistent with the rest of the aircraft or below that level.

Radars detect on variations in reflected signals so the homogenized signal return specially when used with RadarAborbentMaterial [RAM] coatings on other main reflectors such as wing and tail leading edges, air intake lips, and turbine blades will make it very difficult for the enemy to detect you even if you do not have a fully stealth (Very Low Observable [VLO]) airframe.

----------------

Google "Have Glass" for more info

https://theaviationist.com/2012/08/30/have-glass/

"U.S. F-16s tasked to destroy enemy radars, missile batteries to get the same radar-absorbing paint job of the F-35
Aug 30 2012 - 3 Comments
120811-0089-91-0391.jpg

By David Cenciotti
All the U.S. “Wild Weasel” F-16s are being given a new paint job similar to the one of the F-35 Joint Strike Fighter.

It is called “Have Glass 5th generation” as it represents the evolution of the standard Have Glass program that saw all the F-16s receiving a two-tone grey color scheme made with a special radar-absorbing paint capable to reduce the aircraft Radar Cross Section: in fact, “Vipers” are covered with RAM (Radar Absorbent Material) made of microscopic metal grains that can degrade the radar signature of the aircraft.

For the moment, the JSF-like paint job will be applied to the F-16CM (formerly CJ) Block 50 Fighting Falcon aircraft that can carry a variety of air-to-air and air-to-surface ordnance, including HARM (High-speed Anti-Radiation Missiles) and precision-guided munitions.

Their role is to enter the enemy territory ahead of the strike package to take care of the enemy air defenses: radars and fixed and mobile SAM (Surface to Air Missiles) batteries."

----------------

https://manglermuldoon.blogspot.com/2012/05/should-us-sell-taiwan-new-f-16s.html

"Tuesday, May 15, 2012
Should the U.S Sell Taiwan New F-16's?

...



Taiwan's upgraded F-16s will also feature HAVE GLASS II radar reduction treatments which consist of radar absorbent material (RAM) coatings applied to the airframe and an improved canopy which will reflect fewer radar waves. Overall, the HAVE GLASS II treatments will lower the F-16's radar cross section (rcs) and make the F-16's more capable in jamming enemy radars through "reducing the burn-through range (the point at which a radar defeats jamming because the reflection is stronger than the jamming signal)." (Avation Week, 2009) It should be noted that the RAM coatings hardly make the upgraded F-16s qualified as genuine stealth aircraft. To the extent in which the HAVE GLASS II treatments reduce the F-16's rcs are unknown. Official rcs figures for military aircraft are extremely hard to come by if not nonexistent to the public domain. However, what is known is that stealth can only be achieved through both shaping techniques to an aircraft's airframe (e.g. planform alignment design technique) and RAM. Lockheed engineers have stated that stealth is achieved by 80% shaping techniques and 20% by RAM coatings. The fundamental non-stealthy airframe of the F-16 remains unchanged, thus the upgraded F-16s will not be qualified as stealth aircraft. However, these treatments will reduce the detection range of the aircraft to enemy radars in addition to assisting in jamming other radars. In total, at least 1,700 F-16s have undergone HAVE GLASS II treatments. (Lockheed Martin)

Image 4: HAVE GLASS II canopy with signature orange tint



Image 5: F-16 with HAVE GLASS II RAM coating shown below. F-16s with HAVE GLASS II can be identified by its unique rough texture and visual appearance resembling a paint with metallic flakes throughout.

"
 

Attachments

  • Aircraft 101 - Electonic Counter Measures-001-014.pdf
    1.8 MB · Views: 82
  • Aircraft 101 - Electonic Counter Measures-015-035.pdf
    1.2 MB · Views: 224
.
"Radar jamming and deception
From Wikipedia, the free encyclopedia

Radar jamming and deception (electronic countermeasures) is the intentional emission of radio frequency signals to interfere with the operation of a radar by saturating its receiver with noise or false information. There are two types of radar jamming: Mechanical and Electronic jamming.

Contents
Mechanical jamming
Mechanical jamming is caused by devices which reflect or re-reflect radar energy back to the radar to produce false target returns on the operator's scope. Mechanical jamming devices include chaff, corner reflectors, and decoys.

  • Chaff is made of different length metallic strips, which reflect different frequencies, so as to create a large area of false returns in which a real contact would be difficult to detect. Modern chaff is usually aluminum coated glass fibers of various lengths. Their extremely low weight and small size allows them to form a dense, long lasting cloud of interference.
  • Corner reflectors have the same effect as chaff but are physically very different. Corner reflectors are many-sided objects that re-radiate radar energy mostly back toward its source. An aircraft cannot carry as many corner reflectors as it can chaff.
  • Decoys are maneuverable flying objects that are intended to deceive a radar operator into believing that they are actually aircraft. They are especially dangerous because they can clutter up a radar with false targets making it easier for an attacker to get within weapons range and neutralize the radar. Corner reflectors can be fitted on decoys to make them appear larger than they are, thus furthering the illusion that a decoy is an actual aircraft. Some decoys have the capability to perform electronic jamming or drop chaff. Decoys also have a deliberately sacrificial purpose i.e. defenders may fire guided missiles at the decoys, thereby depleting limited stocks of expensive weaponry which might otherwise have been used against genuine targets.
Electronic jamming


German Luftwaffe Tornado ECR.
Electronic jamming is a form of electronic warfare where jammers radiate interfering signals toward an enemy's radar, blocking the receiver with highly concentrated energy signals. The two main technique styles are noise techniques and repeater techniques. The three types of noise jamming are spot, sweep, and barrage.

  • Spot jamming occurs when a jammer focuses all of its power on a single frequency. While this would severely degrade the ability to track on the jammed frequency, a frequency-agile radar would hardly be affected because the jammer can only jam one frequency. While multiple jammers could possibly jam a range of frequencies, this would consume a great deal of resources to have any effect on a frequency-agile radar, and would probably still be ineffective.
  • Sweep jamming is when a jammer's full power is shifted from one frequency to another. While this has the advantage of being able to jam multiple frequencies in quick succession, it does not affect them all at the same time, and thus limits the effectiveness of this type of jamming. Although, depending on the error checking in the device(s) this can render a wide range of devices effectively useless.
  • Barrage jamming is the jamming of multiple frequencies at once by a single jammer. The advantage is that multiple frequencies can be jammed simultaneously; however, the jamming effect can be limited because this requires the jammer to spread its full power between these frequencies, as the number of frequencies covered increases the less effectively each is jammed.
  • Base jamming is a new type of Barrage Jamming where one radar is jammed effectively at its source at all frequencies. However, all other radars continue working normally.
  • Pulse jamming produces noise pulses with period depending on radar mast rotation speed thus creating blocked sectors from directions other than the jammer, making it harder to discover the jammer location.
  • Cover pulse jamming creates a short noise pulse when radar signal is received thus concealing any aircraft flying behind the EW craft with a block of noise.
  • Digital radio frequency memory, or DRFM jamming, or Repeater jamming is a repeater technique that manipulates received radar energy and retransmits it to change the return the radar sees. This technique can change the range the radar detects by changing the delay in transmission of pulses, the velocity the radar detects by changing the doppler shift of the transmitted signal, or the angle to the plane by using AM techniques to transmit into the sidelobes of the radar. Electronics, radio equipment, and antenna can cause DRFM jamming causing false targets, the signal must be timed after the received radar signal. By analysing received signal strength from side and backlobes and thus getting radar antennae radiation pattern, false targets can be created to directions other than one where the jammer is coming from. If each radar pulse is uniquely coded it is not possible to create targets in directions other than the direction of the jammer
  • Deceptive jamming uses techniques like "range gate pull-off" to break a radar lock.[1][2]
Inadvertent jamming
In some cases, jamming of either type may be caused by friendly sources. Inadvertent mechanical jamming is fairly common because it is indiscriminate and will affect any nearby radars, hostile or not. Electronic jamming can also be inadvertently caused by friendly sources, usually powerful EW platforms operating within range of the affected radar. Unintentional electronic jamming is most easily prevented by good planning and common sense, though sometimes it is unavoidable.

Countermeasures
  • Blip enhancement
  • Constantly alternating the frequency that the radar operates on (frequency hopping) over a spread-spectrum will limit the effectiveness of most jamming, making it easier to read through it. Modern jammers can track a predictable frequency change, so the more random the frequency change, the more likely it is to counter the jammer.
  • Cloaking the outgoing signal with random noise makes it more difficult for a jammer to figure out the frequency that a radar is operating on.
  • Limiting unsecure radio communication concerning the jamming and its effectiveness is also important. The jammer could be listening, and if they know that a certain technique is effective, they could direct more jamming assets to employ this method.
  • The most important method to counter radar jammers is operator training. Any system can be fooled with a jamming signal but a properly trained operator pays attention to the raw video signal and can detect abnormal patterns on the radar screen.
  • The best indicator of jamming effectiveness to the jammer is countermeasures taken by the operator. The jammer does not know if their jamming is effective before operator starts changing radar transmission settings.
  • Using EW countermeasures will give away radar capabilities thus on peacetime operations most military radars are used on fixed frequencies, at minimal power levels and with blocked Tx sectors toward possible listeners (country borders)
  • Mobile fire control radars are usually kept passive when military operations are not ongoing to keep radar locations secret
  • Active electronically scanned array (AESA) radars are innately harder to jam and can operate in Low Probability of Intercept (LPI) modes to reduce the chance that the radar is detected.
  • A quantum radar system would automatically detect attempts at deceptive jamming, which might otherwise go unnoticed.[3]

Stealth
Stealth technologies like radar-absorbent materials can be used to reduce the return of a target.

Interference
While not usually caused by the enemy, interference can greatly impede the ability of an operator to track. Interference occurs when two radars in relatively close proximity (how close they need to be depends on the power of the radars) are operating on the same frequency. This will cause "running rabbits", a visual phenomenon that can severely clutter up a scope with useless data. Interference is not that common between ground radars, however, because they are not usually placed close enough together. It is more likely that some sort of airborne radar system is inadvertently causing the interference—especially when two or more countries are involved.

The interference between airborne radars referred to above can sometimes (usually) be eliminated by frequency-shifting the magnetron.

The other interference often experienced is between the aircraft's own electronic transmitters, i.e. transponders, being picked up by own radar. This interference is eliminated by suppressing the radar's reception for the duration of the transponder's transmission. Instead of "bright-light" rabbits across the display, one would observe very small black dots. Because the external radar causing the transponder to respond is generally not synchronised with your own radar (i.e. different PRFs [pulse repetition frequency]), these black dots appear randomly across the display and the operator sees through and around them. The returning image may be much larger than the "dot" or "hole", as it has become known, anyway. Keeping the transponder's pulse widths very narrow and mode of operation (single pulse rather than multi-pulse) becomes a crucial factor.

The external radar could, in theory, come from an aircraft flying alongside your own, or from space. Another factor often overlooked is to reduce the sensitivity of one's own transponder to external radars; i.e., ensure that the transponder's threshold is high. In this way it will only respond to nearby radars—which, after all, should be friendly.

One should also reduce the power output of the transponder in like manner.

Jamming police radar
Jamming radar for the purpose of defeating police radar guns is simpler than military-grade radar jamming.[4]

Jamming in nature
The jamming of bat sonar by certain tiger moth species has recently been confirmed.[5] This can be seen as nature's equivalent of radar jamming."


No


---------------

Short Simplified Answer:

Primarily to reduce radar reflections from inside the cockpit so that they fall to a level more consistent with the rest of the aircraft or below that level.

Radars detect on variations in reflected signals so the homogenized signal return specially when used with RadarAborbentMaterial [RAM] coatings on other main reflectors such as wing and tail leading edges, air intake lips, and turbine blades will make it very difficult for the enemy to detect you even if you do not have a fully stealth (Very Low Observable [VLO]) airframe.

----------------

Google "Have Glass" for more info

https://theaviationist.com/2012/08/30/have-glass/

"U.S. F-16s tasked to destroy enemy radars, missile batteries to get the same radar-absorbing paint job of the F-35
Aug 30 2012 - 3 Comments
120811-0089-91-0391.jpg

By David Cenciotti
All the U.S. “Wild Weasel” F-16s are being given a new paint job similar to the one of the F-35 Joint Strike Fighter.

It is called “Have Glass 5th generation” as it represents the evolution of the standard Have Glass program that saw all the F-16s receiving a two-tone grey color scheme made with a special radar-absorbing paint capable to reduce the aircraft Radar Cross Section: in fact, “Vipers” are covered with RAM (Radar Absorbent Material) made of microscopic metal grains that can degrade the radar signature of the aircraft.

For the moment, the JSF-like paint job will be applied to the F-16CM (formerly CJ) Block 50 Fighting Falcon aircraft that can carry a variety of air-to-air and air-to-surface ordnance, including HARM (High-speed Anti-Radiation Missiles) and precision-guided munitions.

Their role is to enter the enemy territory ahead of the strike package to take care of the enemy air defenses: radars and fixed and mobile SAM (Surface to Air Missiles) batteries."

----------------

https://manglermuldoon.blogspot.com/2012/05/should-us-sell-taiwan-new-f-16s.html

"Tuesday, May 15, 2012
Should the U.S Sell Taiwan New F-16's?

...



Taiwan's upgraded F-16s will also feature HAVE GLASS II radar reduction treatments which consist of radar absorbent material (RAM) coatings applied to the airframe and an improved canopy which will reflect fewer radar waves. Overall, the HAVE GLASS II treatments will lower the F-16's radar cross section (rcs) and make the F-16's more capable in jamming enemy radars through "reducing the burn-through range (the point at which a radar defeats jamming because the reflection is stronger than the jamming signal)." (Avation Week, 2009) It should be noted that the RAM coatings hardly make the upgraded F-16s qualified as genuine stealth aircraft. To the extent in which the HAVE GLASS II treatments reduce the F-16's rcs are unknown. Official rcs figures for military aircraft are extremely hard to come by if not nonexistent to the public domain. However, what is known is that stealth can only be achieved through both shaping techniques to an aircraft's airframe (e.g. planform alignment design technique) and RAM. Lockheed engineers have stated that stealth is achieved by 80% shaping techniques and 20% by RAM coatings. The fundamental non-stealthy airframe of the F-16 remains unchanged, thus the upgraded F-16s will not be qualified as stealth aircraft. However, these treatments will reduce the detection range of the aircraft to enemy radars in addition to assisting in jamming other radars. In total, at least 1,700 F-16s have undergone HAVE GLASS II treatments. (Lockheed Martin)

Image 4: HAVE GLASS II canopy with signature orange tint



Image 5: F-16 with HAVE GLASS II RAM coating shown below. F-16s with HAVE GLASS II can be identified by its unique rough texture and visual appearance resembling a paint with metallic flakes throughout.

"
Chin intake fighters like f16 or j10 can employ dsi intakes to reduce its rcs even further. But maybe it doesnt improve stealth too much as we dont see these types of inlets in Sukhoi T50 which is supposed to be full aspect stealth.
 
.
Bismillah ir Rahman ar Raheem

The Chinese got the Diverterless-Supersonic-Intake [DSI] files from the Locheed Martin [LM] hack and implemented them (well or not) in their existing and upcoming designs. The DSI was initially tested on the F-16:

lockheed_F-16DSI_divertless_supersonic_inlet_3.jpg


The cost of implementing it on legacy airframes has been deemed to be not worth it, at least for the F-16 which already hides its turbine blades well and is not otherwise shaped for Low Observability [LO] in the X-Band ElectroMagnetic [EM] spectrum anyway.

For a clean-sheet design like the F/A-18E/F Super Hornet (designed before LM's development of DSI), Boeing chose to go from the legacy F/A-18A/B/C/D's conventional round inlets to diamond-shaped inlets that hid most of the turbine face:

2081621319_f411f75d51_b.jpg


26500333_nrjj6-m.jpg


The curved slope of the intake ramp, fan baffles (fixed fan-like surfaces in front of the turbine blades), and the parallelogram-shaped diamond inlets scatter Radar EM waves coming from the front in a few directions away from the enemy's radar.

Radar-Absorbent-Material [RAM] application to major reflecting surfaces, composite use, and filling in the Leading-Edge-Root-Extension [LERX] holes also help in supposedly lowering the Super Bug's frontal RCS signature from the legacy Bug's 5-10 square meters range down to the F-16's 1-2 square meters region.

f-22a_02-4034_11_of_11.jpg


Now, the F-22 (above) and YF-23 (below) were the first true stealth fighter (Very-Low-Observable [VLO]) airframes which were designed to bring most frontal and rear RCS figures down into the .0001-.001 square meters region - please note that with radar detection following the inverse fourth power law, if an Su-27 like fighter with a RCS of 15 square meters is detectable at 100 nautical miles, an F-16 like fighter when trimmed to an RCS of under 1.0 square meters can get as close as 50 nautical miles to the enemy before being detected, and a VLO fighter can get to within the 5-10 nautical miles zone or nearly within visual weapons range [WVR].

j9ye52.jpg


The YF-23 above was supposedly even stealthier than the YF-22 though whether it was primarily from the rear where its diamond-shaped wings and sunken exhaust outlets would help greatly or from the front also, I do not know.

3894d0e64401ed98c3d1518ee713bc89.jpg


Ironic that Northrop lost to the Lockheed Skunk Works' F-117 program because while their entry was judged as capable, the slight difference in RCS figures (which would not have mattered operationally) became the deciding factor. When they chose to go with stealth for the YF-23 Black Widow, they lost on maneuverability (granted that the YF-22 was more completely developed with internal weapons carriage and full supercruise performance from the engine the USAF wanted).

Performance is another aspect of inlet design - while DSI's are happiest under Mach 1.6 (limit Mach 1.8-1.9), boundary-layer-splitter type diamond intakes can be more easily designed to supercruise (if they have a turbojet or extremely low bypass ratio [BPR] turbofan with high dry i.e. un-augmented power and good metallurgy to withstand more than a couple of minutes of turbine operation at high temperatures as well as wing-fuselage shaping for low drag in the transonic and supersonic regimes) and can be pushed to beyond Mach 2.0 where the RAM starts degrading anyway.

Of course, the region between the boundary layer splitter plate and the fuselage also needs to be carefully designed in order to not inadvertently reflect EM waves back to the enemy but the same can be said for the DSI's front intake lips.

large_sukhoi_pak-fa_t-50_stealth_fighter_jet_3d_model_max__0d4730eb-6eca-47ca-b9b4-db06bb10dc4d.jpg


You can use all this debate to analyze the T-50 PAK-FA's inlets yourself. To my untrained eyes, the aircraft does not seem as well-designed for VLO as the F-22 and F-35 (particularly from the rear where it is abysmal). However, even with a computer simulation (not to mention anechoic chamber or open-field tests), this is a hard field. Carlo Kopp, despite his many rants, is actually an expert on this matter and you might find the following interesting:

http://www.ausairpower.net/APA-2010-01.html

http://www.ausairpower.net/APA-2012-03.html

Enclosing an analysis of RCS reduction for a legacy fighter (F-5) here.

A better explanation than mine of many basic stealth questions at:

https://basicsaboutaerodynamicsandavionics.wordpress.com/2016/03/04/stealth-techniques-and-benefits/
 

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