PAK-FA and FGFA Thread

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brar_w
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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 13:30

VLO is a broad term and how to achieve a specific value of VLO would depends on many factors like Engineering & Design , Structures/Materials , RAM , Active Measure etc.


Granted that VLO is a broad term, but Low RCS is Low RCS, and from what has been shown as of now the rear aspect is extremely challenged in that department, and things like IRST bulges and a podded FLIR don't make much sense. Things can change however, but by 2016? Either the date is highly optimistic or things won't change all that much

You really cant look at an aircraft and say this one has lower RCS compared to the other because to my eyes and open source information the RCS looks smaller or aircraft has more sheen , A B-2 has no sheen like F-22 but still has lower RCS.


What does SHEEN have to do with it? Indeed it is possible that the F-22 may have better Stealthy coatings than the B-2, but the B-2 may still have much better overall broadband stealth. RAM is one aspect, design and materials is another.

May be the Russians are better with structures/Materials or RAM , similarly the US would be better in some areas.


A big Maybe, since we know the legacy the F-22 and F-35 come from (F-117, B-2, Lockheed and Northrops various other designs that competed wight he F-117 and B-2, Yf22, YF23, stealthy prototypes like halve blue, bird of prey, X-45, x-47, RQ-170 and RQ180) while the Russians have yet to field a basic all aspect LO design let along a VLO design. The R&D boost comes with a program demand, and in the US industry the demand for cutting edge research to lower VLO has been ongoing with active acquisition for over 3 decades. The B-2 that is considered the pinnacle of VLO first flew nearly 25 years ago and these are strong capabilities that it demonstrated many many years ago

[youtube]https://www.youtube.com/watch?feature=player_detailpage&v=Tn4a1SPxry8#t=120[/youtube]



Better access to Theoretical Research and consequently better mathematical equation means lesser and far more efficient effort to do the job and get same result


How can we assume that Russians have done more and better theoretical research in the department of stealth compared to the US, and where do we have evidence that they have access to better mathematical equations and computing to design better stealth aircraft?

I can also ask and say the US never had any acess to S-400 so how can they claim JSF can deal with it


They cannot say with certainty that it will defeat until it actually defeats such a system. That is speculation of a given threat index that they think the S400 brings to the fight and through acquisition and development of highly sophisticated Ground to Air radars and setting those up in testing ranges. The US has some very potent AESA based ground to air radars coupled with very fast networked capability (THAAD, PAC-3, MEADS) not to mention huge X band radars out at sea etc. Of course when the general says that the f-35 can defeat S-400, its just his estimate. This is different from when he talks about the F-35 capability (systems capability) which can be taken to be accurate as that is the capability it brings to the table.

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Re: PAK-FA and FGFA Thread

Postby Austin » 07 Jun 2014 13:35

Stealth is a loosely coined term and can be used in Magazine or Discussion to claim superiority.

But the real essense of stealth lies in Careful Mission Planning , The path the stealth aircraft takes towards a target and the kind of Radar and AD it can encounter are carefully mapped and EW is used aggressively to soften it in disable it , Then Stealth can use its advantage of lower detection threshold to take out the target.

If you bring a B-2 over Indian airspace in peace time even with all its stealth features enabled chances are it will be shot down because there is no mission planning involved to chalk out the optimum route , no EW used to suppress the radar and hence the over lapping radar coverage in different frequency and wave length would be able to easily track the B-2.

The real success of Stealth in all the recent war lies as much in Careful Mission Planning , SEAD as it is about LO , remove one of the 3 from the equation and suddenly your stealth will look vulnerable.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 13:43

Stealth is a loosely coined term and can be used in Magazine or Discussion to claim superiority


Stealth is what it is. You can use it loosely or with some thought put into it. Depends upon who is using it and in what context.

But the real essense of stealth lies in Careful Mission Planning , The path the stealth aircraft takes towards a target and the kind of Radar and AD it can encounter are carefully mapped and EW is used aggressively to soften it in disable it , Then Stealth can use its advantage of lower detection threshold to take out the target


That has been the operational doctrine in the USAF pretty much since the B-2 first flew. Stealth is a combination of VLO (RCS) airframe, IR Suppression, Emcon, and EW ability to defeat threats that still pose a challenge despite of having all that. This has been operationalized by the US decades ago, and the tactics have been verified and operational concepts and "lessons learnt" incorporated into 2nd, 3rd gen stealth designs. These are the advantages of having such an early start.

If you bring a B-2 over Indian airspace in peace time even with all its stealth features enabled chances are it will be shot down because there is no mission planning involved to chalk out the optimum route , no EW used to suppress the radar and hence the over lapping radar coverage in different frequency and wave length would be able to easily track the B-2.


Rebecca grant's book on the B-2, it deals with all of this.

http://www.infibeam.com/Books/b-2-goes- ... wUsedItems

The real success of Stealth in all the recent war lies as much in Careful Mission Planning , SEAD as it is about LO , remove one of the 3 from the equation and suddenly your stealth will look vulnerable


I guess thats where the advantage of having operationalized both VLO designs and worked through multiple "schools" of CONOPS and incorporating these into the design element of stealth aircraft really pays off.

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Re: PAK-FA and FGFA Thread

Postby Austin » 07 Jun 2014 13:50

Again you are simply stating the same fact Russia cannot achieve VLO because it cannot match US industry or exprience and Russia should revel all its card to prove to the world that can do it.

Well it doesnt have to Stealth is a very classified area of research and US , Russia or India or any other country would have little reason to show how it achieved stealth beyond the generic thing known in public , Most aspect of stealth research is classified be it Structures , Materials , Theory , Engineering and many other aspects.

Just as you have stated correctly that the US cannot state with certainty that JSF or Gowler cannot defeat the S-400 system in the same way no one can say with certainty that Russians cannot achieve similar RCS value as F-22 .

And I did not gave a random quote from internet to prove my point I quoted the Chief Designer himself and he mentioned LO goals are similar , Note Similar does not mean identical , I have a quote of the same person who mentioned the average RCS of F-22 is 0.3-0.4m2 and PAK-FA is 0.5 m2 .

So the F-22 and PAK-FA average LO values are not Identical but similar because according to Russians own research in the area of A2A combat in Many versus Many situation , Extreme Agility , Persistance and LO plays an equal role , so they had to incorporate these the characteristics which means they had to get a optimum between the three.

IF you really need to prove the claims of US and Russia for LO then you have to verify it via independent sources , Bring the two types in India verify it against all band X , L ,S, Meter and against a wide range of frequency and in all dynamic situation of air combat as Stealth is a dynamic thing and does not remain constant depending on the Angle of the Aircraft wrt to Radar FOV and also power output of RF.

If you place a X Band Radar say 100-200 meters from F-22 most lowest RCS say Frontal RCS your X band radar would still be able to detect it but if you try to place it few Km away you will get a faint signal from the target ,similar if you try that experiment using RF Frequency in X band and try to place the F-22 in different angle wrt target you will get different returns and if you look from Top or Bottom you get different returns , same goes for B-2 or PAK-FA or PAK-DA.

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Re: PAK-FA and FGFA Thread

Postby Austin » 07 Jun 2014 13:56

I saw you posted some books on Stealth , All opensource books on LO and Radar are just piece of Crap the military of any nation classifies key areas of work and all you get is piece of crums and many times with deliberate distortion of facts.

IF any one on Internet sells you Book on Stealth or Radar its mostly a con artist thing for low level talking point.

Much like Stealth the Work on Modern Radar is a very classified area of work and even to say that Stealth is not detectable against the most common X band radar is very debatable.

Radar has kept with stealth ( I am talking of most Modern AESA and PESA radar ) and it wont be easy to fool a modern radar using LO because they have much better ability to deal with it and yes most of the areas are classified.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 14:15

Again you are simply stating the same fact Russia cannot achieve VLO because it cannot match US industry or exprience and Russia should revel all its card to prove to the world that can do it.


I say nothing of this sort. You bring up valid points about tactics and the entire gambit of how stealthy ops are achieved. I point out that the US has a clear advantage in this department having designed stealth aircraft for decades, having bought them, tested various generations of stealth and taken VLO designs to war.

I am not saying that the Russians can never match the US. With proper investment, time and money they surely can. All i am saying is that the rear aspect of the T-50 looks quite shabby for a VLO fighter. So do things like the IRST Bulb and the fact that they plan of having a FLIR/Targeting Laser designator as a pod.

Well it doesnt have to Stealth is a very classified area of research and US , Russia or India or any other country would have little reason to show how it achieved stealth beyond the generic thing known in public , Most aspect of stealth research is classified be it Structures , Materials , Theory , Engineering and many other aspects.


So there is no real advantage in having demonstrated capability through various industrial efforts over the last decades and of having actually taken the thing to war halfway across the world? When others have quietly built up parity (or surpassed) in the lab despite of having massive budgetary disruptions that lasted for over a decade.

Just as you have stated correctly that the US cannot state with certainty that JSF or Gowler cannot defeat the S-400 system in the same way no one can say with certainty that Russians cannot achieve similar RCS value as F-22 .


It doesn't take a rocket scientist to look at the rear aspect of the current T-50 prototypes and compare the level of stealth to the F-22 or even the YF22 which flew nearly a quarter of a century ago. The same argument can be taken and applied to the claim made by the T-50 designer that the average RCS would be at par with the F-22 (a design that first flew in 1990-91). The designer cannot state that with any level of certainty, while the US general CAN when he claims that the F-35 is stealthier compared to the F-22.

VLO rear-aspect?

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Vs YF 22 prototype (First flight 24 years ago)

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YF 23 (24 years ago)

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Final product (first flight 17 years ago)

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You say that a first full stealthified prototype of the T-50 is yet to take to the air. This compares extremely unfavorably to the F-22 where a fully stealth prototype was in the air in 1991, and a full mission systems enabled F-22 aircraft was in the air in 1997. This is in direct contradiction to the fact that the Russians seem to have caught up or even leapfrogged the US capabilities as far as designing stealth is concerned. Let them at least build a fully stealthy T-50/PAKFA prototype and lets see how the design matures into a fully stealth bird. Let them mount a full systems package into it and then industrialize the production and start churning out aircraft from the factory floor. Its too early to make that call and the evidence we have seen so far calls for an extremely large leap of faith. So far given what is flying its rather unlikely that these prototypes have the all aspect level of VLO that the YF22 and YF23 had around 1989-1992

[youtube]https://www.youtube.com/watch?v=X5aytDSnuxk[/youtube]
[youtube]https://www.youtube.com/watch?feature=player_detailpage&v=HUhOEeYxoZs#t=215[/youtube]

, I have a quote of the same person who mentioned the average RCS of F-22 is 0.3-0.4m2 and PAK-FA is 0.5 m2


Really? The RCS of the F-22 is highly classified and has never been revealed. So its at best what he estimates it to be. Others may estimate differently

So the F-22 and PAK-FA average LO values are not Identical but similar because according to Russians own research in the area of A2A combat in Many versus Many situation , Extreme Agility , Persistance and LO plays an equal role , so they had to incorporate these the characteristics which means they had to get a optimum between the three


Still begs the question, given that the F-22's RCS figures are classified (Even the figures not just the 100's of pages of testing that took months if not years to accomplish) from where are they getting the numbers from?

I saw you posted some books on Stealth , All opensource books on LO and Radar are just piece of Crap the military of any nation classifies key areas of work and all you get is piece of crums and many times with deliberate distortion of facts.


These books are the best resources available to us common people on the performance. Better to read them, to read what pilots, designers have to say then to purely speculate. Even air to air combat books do not get into all the classified elements of air combat, should we also not read them? You have certain views on stealth and how ops and mission planning is important. Where have you got those from? From classified briefings from stealth designers and operators? Or you got these views reading stuff in books or the internet?

IF any one on Internet sells you Book on Stealth or Radar its mostly a con artist thing for low level talking point


Every author's credentials can be checked

http://origin.www.uscc.gov/sites/defaul ... 0grant.pdf

Low level or high level, I do not see anything better. Its better to read published material that only talks about 40% of what is de-classified then to read nothing at all. When actual B-2 pilots talk, people notice specially when they say that they flew right over an F-15 and Mig-29 engagement without either of those birds noticing the B-2.

Radar has kept with stealth ( I am talking of most Modern AESA and PESA radar ) and it wont be easy to fool a modern radar using LO because they have much better ability to deal with it and yes most of the areas are classified.


I guess the designers of stealth don't have access to the most cutting edge radars ;) which only exist with those that do not have stealth designs in the works

One of the largest portable X band radars in the world (24,000+TR elements)

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X and S band AESA

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X Band Gallium nitride AESA

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One of the largest X band radars

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A lot of these radars are made by the same companies that also have high level research on stealth so its not quite that these companies do not know what is going on in the field of radars ;)

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Re: PAK-FA and FGFA Thread

Postby Austin » 07 Jun 2014 19:32

brar_w , I dont have time to write a wall of words but here is something quick point.

1 ) The rear aspect of PAK-FA looks the way it is because its not coated with RAM neither the aircraft ,They have already done LO testing in anechoic chamber but recent news states 7 & 8 Prototype will have LO features , Once the RAM is applied and Ceramic Bric is applied to Nozzle it will reduce its rear RF/IR signature .... for IR signature it does not make much difference as most IIR seeker would have no problems tagging rear signature and hot spots on aircraft , there is a youtube video of F-22 tracked by IR seeker the hotspots are very visible.

2 ) As far as classified RCS signature of F-22 goes its possible but that claim is similar to US General makes of taking out S-400 with JSF , since the capability of S-400 is as much classified , It remains in the realms of claims and counter claims , You will come to know when they encounter each other in real combat.

3 ) As far as Radar goes I am not talking about GaN or GaA radar or how powerful it is , I am talking of the algorithms these radar uses to track targets of different types , Each country keeps these Algorithims of these radars secret much like radars ECM/ECCM features.

So if a US X band radar cannot detect F-22 flying does not mean an Indian ,Russian or Chinese cannot do it using the same band

4 ) Yes I have seen those rear nozzle of F-22 and YF-23 and even JSF , still it does not prove that one design is better than other for rear RCS reduction , Infact recent statement if true states F-35 has lower RCS than F-22 then does that prove conventional serrated nozzle is better than flat one ?

If one design was perfect one for IR and RF reduction they wouldnt have used different way to achieve the same goal , Remember YF-23 lost out to YF-22 not because both didnt meet RCS requirement of USAF but because YF-22 met the production goal requirement of USAF and similarly the X-32 did not loose to X-35 because it did not meet its RCS goals and infact used a combination of blockers to reduce RCS over classic Y Duct.

So you can achieve the same goals of RCS without using any one design as the template there are many ways to skin the cat.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 19:50

The rear aspect of PAK-FA looks the way it is because its not coated with RAM neither the aircraft ,They have already done LO testing in anechoic chamber but recent news states 7 & 8 Prototype will have LO features , Once the RAM is applied and Ceramic Bric is applied to Nozzle it will reduce its rear RF/IR signature ...


And until that actually happens how are we to judge whether it actually can or cannot match up to the F-22 in all aspect VLO?

IIR seeker would have no problems tagging rear signature and hot spots on aircraft , there is a youtube video of F-22 tracked by IR seeker the hotspots are very visible.


From the ground and the goal with IR reduction is not to stop a missile seeker but to stop Long range IRST targeting.

As far as classified RCS signature of F-22 goes its possible but that claim is similar to US General makes of taking out S-400 with JSF


And I'll say to you again what I said then. That claim cannot be taken as 100% gospel (US general's claim). When he speaks about something that he has full access too, that info is important. When he says that the F-35 is survivable to an S400, is his assessment. Until the aircraft actually goes up against the S400 no one will ever know. As the B-2 pilot spoke in the videos of the first B-2 combat sortie. It all boils down to the moment you have to face up the AD.

3 ) As far as Radar goes I am not talking about GaN or GaA radar or how powerful it is , I am talking of the algorithms these radar uses to track targets of different types , Each country keeps these Algorithims of these radars secret much like radars ECM/ECCM features


Yes they do, but the capability of a high powered frequency hop can be built into powerful range radar systems. You will never know exactly what the radar concerned does, but you can build up powerful systems that incorporate the most cutting edge technology as a testing base.

So if a US X band radar cannot detect F-22 flying does not mean an Indian ,Russian or Chinese cannot do it using the same band


Detection is a function of so many things. That the most cutting edge radars in the US find it hard to nail down a f-22 (if), means that it is quite survivable in the frequency range. Nothing more and nothing less.

es I have seen those rear nozzle of F-22 and YF-23 and even JSF , still it does not prove that one design is better than other for rear RCS reduction , Infact recent statement if true states F-35 has lower RCS than F-22 then does that prove conventional serrated nozzle is better than flat one ?


Its not about conventional nozzles vs flat nozzles, its the entire rear assembly. As you mention the T-50 is built in pieces so perhaps the next few prototypes will take care of the overall RCS from the rear aspect. With time we'll know better i guess but at the moment the entire all aspect RCS comparison based on what I see requires a huge leap of faith.

If one design was perfect one for IR and RF reduction they wouldnt have used different way to achieve the same goal


From a design, requirement point of view. The F-35 did not need TVC to begin with, it also needed to have rear nozzle come all the way down for STOVL. By the time the F-35 was developed the LOAN nozzle had verified IR and RCS reduction potential. It is also entirely possible that the F-22 has better rear aspect RCS compared to the F-35, while the F-35 has better frontal and all aspect RCS (overall). The T-50 at the moment employs nothing to "skin the cat". The rear assembly is quite similar to what they do on the Su-35's.

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Re: PAK-FA and FGFA Thread

Postby NRao » 07 Jun 2014 20:18

The "West" certainly has encountered Russian supplied (export) AD - in Syria - and defeated it a few times. So, there is *some* experience there.


Also, the US in particular, and perhaps west in general , has to plan for a wider spectral range than would the Russians or the Chinese. that is not a -ve, just the nature of the beast.

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Re: PAK-FA and FGFA Thread

Postby Austin » 07 Jun 2014 20:23

Yes the current prototype of PAK-FA does not have any RAM treatment or ceramics , Infact there are lot of things out there thats part of system collecting data , So right now its not the production standard with full bells and whistles including LO.

We cannot judge any thing , like I said you cant look at a design and determine its RCS , What the chief designer stated was based on the design goal based on what he looked at the final product , Like how LCA designer stated RCS of Tejas will be 1/3 of M2K long before we even started testing.

The cutting edge radar employing Power Apeture , Freqency hopping , TR module is just one part of the game , You know the frequency of X band and range , you can use hopping etc to try avoid jamming but the key to radar is also the Algorithim and these Algorithims are used to detect a target , Thats what distinguishes in many ways how each country radar capability varies as they use different algorithims to determine the target and other capabilities.

I think you get the point what I am trying to state and we can just agree to disagree on this if we dont and move on. So my last post on the issue.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 20:49

So right now its not the production standard with full bells and whistles including LO.


And yet it will be inducted in a year and a half.

Like how LCA designer stated RCS of Tejas will be 1/3 of M2K long before we even started testing.


With a key difference that we had M2K's for a reference. The Russians have no F-22 to actually put into the lab and test range for an effective RCS analysis. That took the USAF itself years to establish at the various stages of the program.

The cutting edge radar employing Power Apeture , Freqency hopping , TR module is just one part of the game , You know the frequency of X band and range , you can use hopping etc to try avoid jamming but the key to radar is also the Algorithim and these Algorithims are used to detect a target , Thats what distinguishes in many ways how each country radar capability varies as they use different algorithims to determine the target and other capabilities


Like I said, Frequency hopping, and specific algos are all well and good. Its the baseline performance of the stealth in a broad frequency range and against cutting edge computing (back end of the IAD) that is to be tested in the range. No one doubts that each X band radar with India, US, Sweden or Russia has its unique hopping, algos and fast processing. That is not going to solve the inherent weakness of a particular frequency against a particular stealth design. Not to mention that one can throw in the most superior technology for this to try to defeat stealth in the range. I am sure this is actively done and has been since long back when the US actually started designing stealth. You do not need specific algos to judge the inherent advantages of a design compared to a wide frequency range.

I think you get the point what I am trying to state and we can just agree to disagree on this if we dont and move on. So my last post on the issue


amen

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Re: PAK-FA and FGFA Thread

Postby member_26622 » 07 Jun 2014 20:50

Not to be sarcastic, even the Chinese stealth jets rear end looks more stealthy than Russian T-50 :lol:

But the russians are experts at catching up (Look at Russian bomber development videos on youtube) so not too concerned.

This jet will not be in India's hands before 2025~30 for sure. Beyond aeronautics, a stealth jet has a huge amount of effort in sensor integration and software. That's were russians will fall flat on their face. India is better positioned to make this happen.

Reality check - Just look at F-35 pictures by Brar_W, almost ready designwise 20 years back. After that it's just been dogged by software issues. So is the F-22.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 21:06

F-35 designed and ready 20 years back? Where did you get this from? The bare bone prototype flew in 2000. The first production representative aircraft flew in 2006 and the IOC after all the delays (some before the first flight, other after) is to be in 2015. The F-22's 4 prototypes (2 YF22's and 2 YF23's) flew in 1990 and 1991 iirc. And the aircraft IOC'd 14 years later. It could have IOC'd in 2000 had successive governments not slowed down the program considerably while they were FIGURING out whether to cancel it or not ( a 2-3 year delay just because of that). So yes it takes time, yet were are being told that despite of not having a fully complete airframe (From a VLO point of view) and not having full system hardware on the airframes or the initial mission integrated software load the jet will somehow miraculously IOC in 2016.

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Re: PAK-FA and FGFA Thread

Postby member_22605 » 07 Jun 2014 21:18

3D models of the F-35, F-22 and the T-50 are available online(fairly accurate ones). Any person with a sound understanding of physical optics/Geometric optics can write a straight forward code to find out the RCS of the model(monostatic/bistatic) or use some wonderful EM simulation software like FEKO(if you have the money) which gives a highly accurate RCS value of the model. This may not be the precise RCS value but it does give an idea as to which is a better VLO design(this is assuming the dielectric constant of the material is the same across the all these aircrafts). IF you were to conduct this exercise then you would know why the chief designer said what he said.

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Re: PAK-FA and FGFA Thread

Postby member_22605 » 07 Jun 2014 21:25

MATLAB users should try this. It is an awesome code and is free :D . Its a lot of fun too please check it out
http://www.mathworks.in/matlabcentral/f ... pofacets.m

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 21:30

raghuk wrote:3D models of the F-35, F-22 and the T-50 are available online(fairly accurate ones). Any person with a sound understanding of physical optics/Geometric optics can write a straight forward code to find out the RCS of the model(monostatic/bistatic) or use some wonderful EM simulation software like FEKO(if you have the money) which gives a highly accurate RCS value of the model. This may not be the precise RCS value but it does give an idea as to which is a better VLO design(this is assuming the dielectric constant of the material is the same across the all these aircrafts). IF you were to conduct this exercise then you would know why the chief designer said what he said.


So many variables here that its basically pointless for any comparison that values a very high degree of specificity regarding the range of the number to be small. RAM, materials, degradation of stealth at the ops level, IR signature etc. There is no substitute to throwing a design in a range in a lab and against fighters equipped with specifically designed IR sensors to get readings from all angles and at all altitudes/conditions. The ATF program had a lockheed martin design testing report and plan which was 20,000 pages thick. A lot of those pages had to do with the shaping, stealth, RCS and plans to build on those. Despite of having all that hard information, they still spent a lot of time testing full production representative jets for RCS and IR and on the pole, pre delivery and routinely pitting them against radars at the test ranges. This shows the importance of the actual materials, construction tolerances and precise construction to the overall RCS of any stealth aircraft.

Image
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Image

http://www.thehowlandcompany.com/radar_ ... d_F-35.htm

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Re: PAK-FA and FGFA Thread

Postby member_22605 » 07 Jun 2014 21:58

I never said that the simulated values are the precise RCS values. I do know how RCS is evaluated and we(India) do have similar facilities to test the RCS physically(it isn't as TFTA as the pics you posted :wink: ) . And i did say that the RCS values obtained from these simulations are just first cut and all this is assuming the same dielectric constant across the aircrafts. Anyway I just suggested it because i think its a lot of fun using these tools and also, field theory was my favorite subject while i was in college.
cheers!

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Re: PAK-FA and FGFA Thread

Postby member_26622 » 07 Jun 2014 22:05

brar_w wrote:F-35 designed and ready 20 years back? Where did you get this from? The bare bone prototype flew in 2000.


Yes, the bare bone prototype which looks much better stealth wise compared to the T-50. Even the chinese J-3X stuff looks good.

I can't run Matlab stuff but using good old eyeballs :D

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Re: PAK-FA and FGFA Thread

Postby Viv S » 07 Jun 2014 22:14

Austin wrote:Remember YF-23 lost out to YF-22 not because both didnt meet RCS requirement of USAF but because YF-22 met the production goal requirement of USAF and similarly the X-32 did not loose to X-35 because it did not meet its RCS goals and infact used a combination of blockers to reduce RCS over classic Y Duct.


The production variant of the YF-23 would have employed DSI with a very tiny bit of the compressor face exposed from the front.

As far as the X-32 went, the prototype was rejected because of its VSTOL performance, but the RCS would have been an issue as well. The Y-duct wasn't an option for the X-32 since it employed (Harrier-like) vectored nozzles for VTOL operation, as a result of which the engine was sited far ahead in the fuselage (ahead of the CoG as a matter of fact).

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Re: PAK-FA and FGFA Thread

Postby brar_w » 07 Jun 2014 23:04

Remember YF-23 lost out to YF-22 not because both didnt meet RCS requirement of USAF but because YF-22 met the production goal requirement of USAF and similarly the X-32 did not loose to X-35 because it did not meet its RCS goals and infact used a combination of blockers to reduce RCS over classic Y Duct.


From what I have read on the matter, the papers or the evaluation report has not been made public. The reason most often sighted was that the YF22 and the proposal for advancement of design and overall production offered by lockheed martin and Boeing was much more advanced from a development, reliability, maintainability and risk point of view. Simply put a less risky and easier design won over a more stealthy and complex (to mass produce and develop) proposal from a company that focused all out on stealth and super cruise, and did not offer as compelling a roadmap for further development and risk reduction as the program transitioned into developmental testing and eventual induction (the entire roadmap had to be published well in advanced during the time of the ATF).

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Re: PAK-FA and FGFA Thread

Postby Cain Marko » 08 Jun 2014 03:17

Just a point for folks to note (in terms of Pakfa being inducted by 2016):

Russian induction process is not exactly the same as others. IIRC, the flanker was "inducted" well before the final version as such. So induction does not mean operationalization.

A questions about the rear comparison between T-50 and F-22, what exactly are we looking for in terms of differences in terms of RCS?

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Re: PAK-FA and FGFA Thread

Postby Karan M » 08 Jun 2014 03:56

Guys - please understand. Russians are pragmatic and not dumb. Radar performance attenuates like crazy for receding targets, to the order of 60%. An untreated Pakfa would still be flying very high and fast, making shots in that quadrant very hard, especially if the PAKFA is backed up by jamming (disposable jammers) as has been hinted.

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Re: PAK-FA and FGFA Thread

Postby Viv S » 08 Jun 2014 07:32

Karan M wrote:Radar performance attenuates like crazy for receding targets, to the order of 60%.


For AESAs?

An untreated Pakfa would still be flying very high and fast, making shots in that quadrant very hard, especially if the PAKFA is backed up by jamming (disposable jammers) as has been hinted.


Perhaps for hit-and-run attacks, but we also need something that can take on the S-300/400 class systems and carry out deep interdiction/strikes.

Also flying high altitudes has the downside of making the aircraft easier to acquire for IR sensors.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 08 Jun 2014 09:15

A questions about the rear comparison between T-50 and F-22, what exactly are we looking for in terms of differences in terms of RCS?


Between the f-22 and the apparently incomplete t-50 prototypes currently in the air.

The t-50 entire engine assembly is devoid of any LO feature. Shaping or RAM or any sort of material that acts as a dual RCS lowering and IR signature reducing material for the rear aspect. The rear assembly is quite similar to that of the Su-30 , 35 family. The nozzles also appear to be fairly standard Flanker family type. The F-22's are highly RCS and IR favorable nozzles using ceramics and other materials. The F-35's nozzles are also specifically designed with quite a bit of testing through the LOAN program which tested the nozzle in a surrogate F-16 before such a nozzle could be used on the f-35 program. As Austin suggests, the Russians are building LO onto the T-50 in parts and it won't be till perhaps the 8th or 9th prototype that they manage to cover the rear aspect with LO features (not sure i get this approach). But other points still point to a lack of LO features like the IRST bulb and the podded FLIR/laser designator etc. Lets see how this design matures but its become increasingly apparent that even with our money going into the project it would be a decade at least before we get to see anything substantial that incorporates all mission systems currently planned and the 40 odd changes that we have wished for (But apparently the head of the program says that FGFA=PAKFA). A new engine may take even longer. We need to prepare for that timeline. Its the correct fighter for the IAF, i have no doubts on that but we need to have the proper prospective as to how much development actually remains and where it needs to head before it starts to fulfill what the designers have promised.

Image



The F-22, which had a custom built engine around the 5th gen requirements (Which the PAKFA should get a decade or so down the road) had stringent requirements in that department as well, and this was a criteria that was looked at when it was selected as the winner from the GE F-136 engine in the early 90's. The testing did not end there. The program took the engines and took the design assembly and created a testing assembly that measured on the ground the rear RCS and IR signature of the overall assembly to better FINE TUNE cooling solutions and to check whether the IR signature requirements were being met or not (This was the same on the B-2 program as well).

The aircraft’s engines are major signature contributors in the rear of the aircraft. The F-22 uses two Pratt & Whitney F119 engines coupled with 2D thrust vectoring exhaust nozzles. Integration of these powerful, high-temperature engines into the airframe was an extremely difficult design challenge. The rear end of the engine is largely exposed to radar. The multi-bounce effects caused by the nozzle cavity and nozzle flaps, and the large gaps required for thermal expansion and for nozzle movement complicate the situation. An extensive test program was conducted on a full-scale twin nozzle model to make design trades and to generate a final design


As you can see in this picture, a dedicated full scale engine assembly test model was prepared for the specific purpose of overall measurement and testing of all elements of this. All the F-22 (just like the B-2) was also covered in a Boeing designed stealthy topcoat for IR protection.

http://s1.postimg.org/4gmokdrxb/F_22_pr ... e_demo.png


More on the stealth, the materials, the testing and the overall process and IMPORTANCE of taking stealth from the prototypes to the manufacturing process and churning out stealthy aircraft is also covered in the lockheed martin white paper on stealth (more pics). That the job is not over at the design level is of importance. An entire industrial complex was created just to verify that each F-22 (and this is also done on each F-35) created on the production line was being created to high degree of tolerances and had its RCS measured to verify this. The F-35 does this at all levels as well.

And just to highlight a point one of the forum members made a while ago about the F-22 and F-35 antennas being passive only and those on the PAKFA being active and passive >

The F-22 Raptor’s antenna suite includes a large number of embedded and conformal antennas. Antennas are designed to receive and radiate energy


http://www.f22fighter.com/AffordableStealth.pdf

I'll try to open up some older book I have on the F-22 to see if I can shed some more light. These links are what I knew about the program and could find through searching other forums and the internet. Will get more on the exact processes. I think there was an interview with ATK on youtube which showed how the Nacelles for example were produced for the F-35 engine assembly.


Here is how F-35's Low Observable coatings are applied.

[youtube]https://www.youtube.com/watch?v=JwvZLqtAZWY[/youtube]

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Re: PAK-FA and FGFA Thread

Postby Cain Marko » 08 Jun 2014 10:04

Viv S wrote:
Karan M wrote:Radar performance attenuates like crazy for receding targets, to the order of 60%.


For AESAs?

INteresting point Karan, I did forget about this aspect. VivS, even if an AESA FCR doesn't degrade to the degree of a mechanically scanned counterpart, the AAM's seeker performance probably will?

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Re: PAK-FA and FGFA Thread

Postby brar_w » 08 Jun 2014 10:20

Karan M wrote:Guys - please understand. Russians are pragmatic and not dumb. Radar performance attenuates like crazy for receding targets, to the order of 60%. An untreated Pakfa would still be flying very high and fast, making shots in that quadrant very hard, especially if the PAKFA is backed up by jamming (disposable jammers) as has been hinted.


Disposable jammers are already operational elsewhere. The problem is not as much with receding targets (Russian homeland defense would mean that very little of those situation would arise for russia) but to send an aircraft against an integrated air defense where both the active elements and the passive elements are not power limited. All aspect stealth is very important in those situation and has been emphasized in all the stealth designs we have seen till date, fighter, bomber or UAV. It may not matter to the Russians that will have a stealthy strategic bomber. For us long range penetrative strike against modern Air defenses means sending in PAKFA's. Even in air to air, the radar is hardly the only element in modern 4.5 ten and 5th generation aircraft that will be used to detect the backside of a stealthy aircraft. The X band sensor in the back will be emitting. and the overall returns would also be there. Systems like the ALR-94, embedded sensors, The main FCR all work to detect the aircraft. This is true for most 4th generation and 5th generation designs. The earlier notion that radar returns are reduced are all well and good but modern systems are integrated and not federated, detection techniques and technology has moved onto sensor fusion and as such limits of a RCS return are compensated to some extend by passive detection using embedded antennas.

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Re: PAK-FA and FGFA Thread

Postby Karan M » 08 Jun 2014 10:36

Viv S wrote:
Karan M wrote:Radar performance attenuates like crazy for receding targets, to the order of 60%.


For AESAs?

An untreated Pakfa would still be flying very high and fast, making shots in that quadrant very hard, especially if the PAKFA is backed up by jamming (disposable jammers) as has been hinted.


Perhaps for hit-and-run attacks, but we also need something that can take on the S-300/400 class systems and carry out deep interdiction/strikes.

Also flying high altitudes has the downside of making the aircraft easier to acquire for IR sensors.


All radars. AESAs at the end of the day are basically able to rapidly increase revist rates but the fundamental challenges remain.

For SEAD the Russians are develiping a bunch of new long range ARMs.

IR sensors will detect a PAKFA anyhow rear quadrant detection or not the greatest protection will be the combination of height and speed.

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Re: PAK-FA and FGFA Thread

Postby Cain Marko » 08 Jun 2014 10:39

brar_w wrote:
A questions about the rear comparison between T-50 and F-22, what exactly are we looking for in terms of differences in terms of RCS?


Between the f-22 and the apparently incomplete t-50 prototypes currently in the air.

The t-50 entire engine assembly is devoid of any LO feature. Shaping or RAM or any sort of material that acts as a dual RCS lowering and IR signature reducing material for the rear aspect. The rear assembly is quite similar to that of the Su-30 , 35 family. The nozzles also appear to be fairly standard Flanker family type. The F-22's are highly RCS and IR favorable nozzles using ceramics and other materials. The F-35's nozzles are also specifically designed with quite a bit of testing through the LOAN program which tested the nozzle in a surrogate F-16 before such a nozzle could be used on the f-35 program. As Austin suggests, the Russians are building LO onto the T-50 in parts and it won't be till perhaps the 8th or 9th prototype that they manage to cover the rear aspect with LO features (not sure i get this approach).
But then, keeping in mind what Austin has pointed out (that the Pakfa with full LO features is yet to be seen), the pictorial comparison is premature isn't it? Also, the design is far cleaner than the flanker series.
But other points still point to a lack of LO features like the IRST bulb and the podded FLIR/laser designator etc. Lets see how this design matures but its become increasingly apparent that even with our money going into the project it would be a decade at least before we get to see anything substantial that incorporates all mission systems currently planned and the 40 odd changes that we have wished for (But apparently the head of the program says that FGFA=PAKFA). A new engine may take even longer. We need to prepare for that timeline.
Frankly, I think the timeline is not well understood. So far, they have come up with 6 prototypes in 4 years, and testing has been quite robust. The real deal will be available by around 2018, at least after PV 8 and 9Its the correct fighter for the IAF, i have no doubts on that but we need to have the proper prospective as to how much development actually remains and where it needs to head before it starts to fulfill what the designers have promised.
Agreed, folks involved should have a good idea even though open sources hardly provide any worthwhile clarity
The aircraft’s engines are major signature contributors in the rear of the aircraft. The F-22 uses two Pratt & Whitney F119 engines coupled with 2D thrust vectoring exhaust nozzles. Integration of these powerful, high-temperature engines into the airframe was an extremely difficult design challenge. The rear end of the engine is largely exposed to radar. The multi-bounce effects caused by the nozzle cavity and nozzle flaps, and the large gaps required for thermal expansion and for nozzle movement complicate the situation. An extensive test program was conducted on a full-scale twin nozzle model to make design trades and to generate a final design


As you can see in this picture, a dedicated full scale engine assembly test model was prepared for the specific purpose of overall measurement and testing of all elements of this. All the F-22 (just like the B-2) was also covered in a Boeing designed stealthy topcoat for IR protection.

More on the stealth, the materials, the testing and the overall process and IMPORTANCE of taking stealth from the prototypes to the manufacturing process and churning out stealthy aircraft is also covered in the lockheed martin white paper on stealth (more pics). That the job is not over at the design level is of importance. An entire industrial complex was created just to verify that each F-22 (and this is also done on each F-35) created on the production line was being created to high degree of tolerances and had its RCS measured to verify this. The F-35 does this at all levels as well.

The problem here is that while much has been made public about the development of the F-22's engines, v.little is known about what is going on with the article 117 thanks partly to the russian tendency to keep things under wraps, partly to a loss in translation, and partly to poor PR. This does not automatically disqualify the Russian engine development however, we simply don't know what they are doing (although we do know that they are doing something). These reasons have contributed to other erroneous conclusions about Russian h/w as well, for e.g. for the longest time it was said that the R77 AAM did not have a lofted trajectory, while in fact it does. To me, it seems that the Russians have not gone through all the trouble in shaping, alignment, composite usage, materials development etc. etc. to leave obvious and gaping holes elsewhere. That is simply insulting their intelligence.

And just to highlight a point one of the forum members made a while ago about the F-22 and F-35 antennas being passive only and those on the PAKFA being active and passive >
Well, it is not like the F-22/35 will not use active sensors at all, if that were the case, why even have them? Conversely, it is not as though the pakfa will only use active sensors all the time - one doubts that they will be continuously emitting. A lot here will depend on training and tactics

The F-22 Raptor’s antenna suite includes a large number of embedded and conformal antennas. Antennas are designed to receive and radiate energy


http://www.f22fighter.com/AffordableStealth.pdf

I'll try to open up some older book I have on the F-22 to see if I can shed some more light. These links are what I knew about the program and could find through searching other forums and the internet. Will get more on the exact processes. I think there was an interview with ATK on youtube which showed how the Nacelles for example were produced for the F-35 engine assembly.

Here is how F-35's Low Observable coatings are applied.
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Re: PAK-FA and FGFA Thread

Postby Karan M » 08 Jun 2014 10:41

brar_w wrote:
Karan M wrote:Guys - please understand. Russians are pragmatic and not dumb. Radar performance attenuates like crazy for receding targets, to the order of 60%. An untreated Pakfa would still be flying very high and fast, making shots in that quadrant very hard, especially if the PAKFA is backed up by jamming (disposable jammers) as has been hinted.


Disposable jammers are already operational elsewhere. The problem is not as much with receding targets (Russian homeland defense would mean that very little of those situation would arise for russia) but to send an aircraft against an integrated air defense where both the active elements and the passive elements are not power limited. All aspect stealth is very important in those situation and has been emphasized in all the stealth designs we have seen till date, fighter, bomber or UAV. It may not matter to the Russians that will have a stealthy strategic bomber. For us long range penetrative strike against modern Air defenses means sending in PAKFA's. Even in air to air, the radar is hardly the only element in modern 4.5 ten and 5th generation aircraft that will be used to detect the backside of a stealthy aircraft. The X band sensor in the back will be emitting. and the overall returns would also be there. Systems like the ALR-94, embedded sensors, The main FCR all work to detect the aircraft. This is true for most 4th generation and 5th generation designs. The earlier notion that radar returns are reduced are all well and good but modern systems are integrated and not federated, detection techniques and technology has moved onto sensor fusion and as such limits of a RCS return are compensated to some extend by passive detection using embedded antennas.


Irrelevant whether jammers operational elsewhere. Point is PAKFA may take a much more pragmatic approach to breaking the kill chain than relying on VLO or passive measures alone depending on the circumstances. Given its overall lower averaged RCS jamming has to attenuate suppress only specific hotspots.
Next, basic facts remain FCRs struggle with receding targets and remain the primary weapons guidance systems for BVR targets. Also the PAKFA has air to air clearly as its first priority. For strike long range munitions will be used. Our challenge is to marry the PAKFA concept with our needs if the FGFA requirements are not implemented but then again we have a long history of managing much more with far more limited platforms.

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Re: PAK-FA and FGFA Thread

Postby brar_w » 08 Jun 2014 10:58

For SEAD the Russians are develiping a bunch of new long range ARMs


Anti radiation missiles for SEAD cover only one element of the kill chain that must be broken to completely remove the IAD thread. When an increasing number of passive elements are added to the mix, those passive elements need to be spotted in the clutter during the fog of war and dealt with. Similarly IAD's are totally net-centric now days, with multiple radars that emit very little but do so strategically/in sync that make them extremely difficult to target in real time using ARM's, especially from long ranges. Add to that the fact that Russian and Chinese IAD's are increasingly looking at decoy emitters and your problems are further compounded. Add to that protection and a saturation attack may be the best way to target them. Expect this to get even worst in the coming decade (s). Even the last few conflicts have shown that relying solely on long (er) range ARM's is not the be all end all of targeting a nicely set up IAD net. The pacific nations and the US that is preparing for the same IAD thread vis-a-vis China are reducing their reliance on ARM targeting to actually going in and finding these elements of the IAD in the clutter and through the vast cammo techniques using high quality discriminating sensors. There is no substitute for looking for things to pick of and then targeting them, if we think a S400/500 and China's son_of_S300_clone :) would present a nice emitting target long enough for you to paint with a long range ARM then we are going to be surprised. Non permissive environment ISR ability, High quality IR sensors are your primary drivers when you need to get into the area, search for hidden IAD elements, passive elements, decoys and backup radars that can be setup or turned on in a moment's notice. China is a unique case quite different from Pakistan. They are designing an IAD setup that has to defeat the US anti-A2AD elements and the ability to develop and field any number of ARM missiles that it so wishes. To rely on ARM targeting for a majority of IAD destruction was foolish in Kosovo and Iraq, and it would be quite foolish against any competent threat that has invested heavily on a IAD that is actually designed around A2AD

Irrelevant whether jammers operational elsewhere.


Quite relevant sir when the chinaman has already started to seriously look into tactics, technology and capability to counter this.

http://www.airforcemag.com/Features/new ... 0mald.aspx

The IAD vs A-IAD scenario between China and USA/Japan/SK is playing out quite fast, and with close to a 150 Billion dollar defense budget china will not sit quietly without developing strong counter capability.

China has developed a national integrated air defense system (IADS) to defend key strategic cities and borders, territorial claims, and forces against threats from the air. Overall, China’s IADS represents a multilayered defense consisting of weapons systems, radars and C4ISR platforms working together to counter multiple types of air threats at various ranges and altitudes. One of China’s primary goals is to defend against precision strike munitions such as cruise and ballistic missiles, especially those launched from long distances.


China’s IADS also includes a C4ISR network to connect early warning platforms, SAM and AAA, and command posts in order to improve communication and response time during operations. The network is intended to include battle damage assessment capability. China continues to make progress on command, communication, and control systems. China’s air defense brigades are training to use this information network and mobile C2 platforms to connect different types of weapons systems’ operations together by sending automated targeting information to them simultaneously. Weapon systems that are geographically separate, in different units, and a mix of older and newer battalions could achieve compatibility through the use of networked C2. China is also using simulation systems to attempt to train for command of air defense operations in realistic operational conditions, including network warfare.





http://www.scribd.com/fullscreen/213883 ... ode=scroll

I about a decade we should see what the S-400 system acquisition has done to china's own AD setup and how fast they can clone it and which elements they decide to clone and add to its next AD systems.
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Re: PAK-FA and FGFA Thread

Postby brar_w » 08 Jun 2014 11:08

Next, basic facts remain FCRs struggle with receding targets and remain the primary weapons guidance systems for BVR targets.


That was true for 4th gen. Modern integrated systems need not use the FCR as the major SA element for a missile. Even in the F-22, whose ALR-94 first flew more than 2 decades ago (as a benchmark where this technology can go 10 or even 20 years from now where the PAKFA will be a dominant player), the ability to either assist the radar for detecting and/or tracking threats where the radar may be "challenged" or detect and track emitting threats automatically with enough information/clarity to launch a weapon. The main point in that engagement (Rear end) is not the targeting per say but the missile performance against a super cruising capable bird ;) which may explain why the russians are pragmatic and may leave it less complete compared to the frontal RCS. Against incoming Aim-120's from east Europe it is more than adequate, however when a J-20 gets the ability to pass on a passive or active track of the T-50 butt to a strategically placed SAM the scenario may require a different level of stealth

A BAE Systems AN/ALR-94 passive receiver system, which has capabilities along the lines of a "radar homing & warning system (RHAWS)" used on a defense-suppression aircraft, able to detect, characterize, locate, and target emitters. It is an extremely sophisticated system and provides 360 degree coverage. It can detect emitters at ranges beyond that of the AN/APG-77 radar, cue the radar onto the target, or provide direction for AMRAAM attacks against an emitter without use of the radar system at all.


http://www.airvectors.net/avf22.html

Also the PAKFA has air to air clearly as its first priority.


I understand that from the russian pov, but for us the PAKFA MKI needs to be a capable multi-role fighter. It would be a potent IAD enabler for us in an offensive op against a credible air defense force. Russians can fall back on the PAKDA for that, we have nothing with that stealth, range, speed (PAKFA) or armament in the pipeline. Anti access is an enabler for offensive ops. If the enemy knows your strike fleet is limited to areas where it can act comfortably then its own offensive/strategic ambitions are considerably emboldened. We have to deal with the Chinese IAD threat, and the PAKFA MKI needs to bring home that capability. The AMCA is the smaller "cousin" to it, but we are not going out and looking to build a 70,000 pound of thrust GIANT in the AMCA with the sort of range and speed the PAKFA can bring to the fight. The AMCA may well be more stealthy, but we have our own pragmatic things to worry about.

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Re: PAK-FA and FGFA Thread

Postby NRao » 08 Jun 2014 18:50

I can see and expect to see a FGFA (much like the $20+ billion dollar Rafale), but I would be unpleasantly surprised if the IAF accepts Mr. P's statement that the PAK-FA - as is - meets the IAF's "stringent" requirements.

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Re: PAK-FA and FGFA Thread

Postby member_22605 » 08 Jun 2014 20:46

As per the IAF's stringent requirements, the F-35 is no where close and if any fighter can meet all those requirements it will be the AMCA. The FGFA will be a compromise in the meanwhile.
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Re: PAK-FA and FGFA Thread

Postby member_22605 » 08 Jun 2014 21:03

Its not that the Russians can't deliver and I havent seen any solid proof supporting this claim. The T-50 is built around the RuAF specs just as the Su-27 was, we managed to make an Su-30MKi out of the UB and if we can make an FGFA which the IAF is happy with then its job done. My point here is that no product unless designed by ourselves will ever meet all our operational requirements. The services in the meanwhile also have to remain pragmatic and realistic, a mixture of the best specs from platforms around the world isn't the best ASR.
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Re: PAK-FA and FGFA Thread

Postby Sancho » 08 Jun 2014 21:03

Viv S wrote:
Austin wrote:Remember YF-23 lost out to YF-22 not because both didnt meet RCS requirement of USAF but because YF-22 met the production goal requirement of USAF and similarly the X-32 did not loose to X-35 because it did not meet its RCS goals and infact used a combination of blockers to reduce RCS over classic Y Duct.


The production variant of the YF-23 would have employed DSI


Based on? Especially since it's a misconception that DSI has anything to do with hiding the compressor blades, which it hasn't at all! Fighters that currently use that feature to improve the airflow to the engine, also uses either S- or Y-ducts and these ducts hide the engines.
More over, there is still the option of radar blockers in front of the engine to achive the same goal and we already see that in the F18SH, the Gripen, just like the Japanese 5th gen fighter is developed with the same feature, which is still the most rumored choice for the Pak Fa / FGFA as well.

Also the current engine front is tilted downwards, while the rear end is placed much higher, similar to the YF23. So lets assume they locate the Type 30 engine later in a straight line, you would have the same solution with a lower air intake and a higher engine compressor, just as it was done for the YF23 or as it seems to be planned for the Japanese stealth fighter:

Image
Image


So when Northrop Grumman, Boeing and Mitsubishi design stealth fighters without a propper S-Duct, why is it suddenly wrong when Sukhoi does it too?

The fact is, there is a lot of bias against the Russians and the blind believe that anything from the US is the only solution, especially for stealth.

Viv S wrote:All the PAK FA's electro-optical sensors bulge out of the airframe, in contrast to the F-35 where there's been a focus on retaining the aircraft's VLO capability.


Typical example for ignoring the reality, the MAWS under the fuselage of the F35 are "bulging" out the same way they are at the T50 below the cockpit or at the tail sting, while the side MAWS behind the cockpit of the T50 are fully integrated just as they are in the F35.
On the other side, EOTS is obviously bulging out of the airframe as well, the only reason why you don't complain about it is, that the windows are stealthy shaped. By the same logic, all that the IRST of the T50 needs is a shaped window right?
And what about the gun of the F35A, that is not fully integrated to the airframe, but is bulging out in a similar manner as the alledged missile pods of the T50 under the wings? Both are shaped in a similar way to divered radar waves, but do you consider that as a flaw of the F35 too (don't want to start about the fact that the F35B has only an external gun pod or that all the early F35s are likely to carry IR missiles externally only, if at all...)?

When you put all the bias aside and acknowledge,

- that the leading edges and the airframe (except of the stopgap engine coverings) of the T50 are shaped in a similar way as it is on every other stealth fighter
- that the airframe or the weapon bays include sawtooth design
- that the electro-optics are as integrated as it is the case for the F35
- that the serial production varient will use similar materials and coatings
- and the fact that it carries all weapon and fuel loads internally
- and most importantly, that the final Pak Fa and FGFA with the type 30 engine might come with the changes IAF required a few years back

...you simply can't honestly deny that it's a VLO stealth fighter design!

If the final Pak Fa and FGFA will be at the same stealth level of the F22 in this field needs to be seen, but it surely will be able to compete with the F35, while outclassing both US fighters in flight performance or load areas. The more we can customize our version, the better we can make it in terms of EW, sensor fusion or weapons, with minor changes to make it more stealthy too.

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Re: PAK-FA and FGFA Thread

Postby NRao » 08 Jun 2014 21:06

Its not that the Russians can't deliver and I havent seen any solid proof supporting this claim


Not sure what other proof one requires. There was only one source for that statement - the IAF. Is that not proof enough?

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Re: PAK-FA and FGFA Thread

Postby member_22605 » 08 Jun 2014 21:11

Mr shukla in my opinion is just an F-35 fanboy with little to no information and he does add a lot of BS to his articles. I still remember his LCH articles and that for me is enough to judge his writings.

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Re: PAK-FA and FGFA Thread

Postby NRao » 08 Jun 2014 21:12

raghuk wrote:Mr shukla in my opinion is just an F-35 fanboy with little to no information and he does add a lot of BS to his articles. I still remember his LCH articles and that for me is enough to judge his writings.


We have been through thsi before. What does a statement from the IAF have to do with Shukla?

You could have quoted that and it would have been as valid.

What is so difficult to understand in that? The statement was from the IAF.

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Re: PAK-FA and FGFA Thread

Postby NRao » 08 Jun 2014 21:15

a mixture of the best specs from platforms around the world isn't the best ASR


Thanks!!!!

That is exactly what I said a few pages ago.

IF one were to take the ASR supposedly issued for the AMCA - it requires a "fully stealth" (whatever that means) air craft.

The PAK-FA is not a "fully stealth" air craft - by Sukhoi's own admission.

So, that for one should imply that the IAF is right - that the Russians cannot deliver.

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Re: PAK-FA and FGFA Thread

Postby Sancho » 08 Jun 2014 21:36

brar_w wrote:things like IRST bulges and a podded FLIR don't make much sense.


The IRST of the T50 is bulging out of the airframe, the same way as the EOTS does at the F35, the only difference is, that the EOTS has shaped windows and if that isn't a requirement for the Russians currently at their early version, that's up to them, just like how they want to use the early Pak Fa in in strike role, because that decides if the external LDP makes sense or not.
The F22 AND the F35 will primarily use satellite guided weapons from stand off ranges in the first days of a war. Laser guided weapons like LGBs or ATGMs on the other side would be too risky because of the low range and the fact that most heavy LGBs doesn't fit into the weapon bays anyway. That means the EOTS mainly will be used in CAS, when the risk is low and full stealth capability is not required. In fact, it is even likely that it will use it's external stations in such roles too, to increase the weapon loads or add more fuel to extend endurance.

Similarly the Russians will use long range weapons from their weapon bays in the early stages and might opt for simple laser guided weapons and the external LDP for later CAS roles, just like an F22 would do it if it would carry LGBs. With large numbers of Flankers and especially the Su 34 in their fleet, they might divert the basic CAS roles to these fighter and the Yak 130 as it seems.

So an integrated EOTS is not always an advantage and used as a compromised IRST it's even a bad solution, compared to the OLS of the Russians. But without this IRST mode, the whole system would just be added weight, drag and most likely RCS during A2A roles, where it's not need. But A2A roles are what the PaK fa or the F22 are primarily meant for!


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