Russian Su-57 Aircraft Thread (PAK-FA and IAF FGFA)

[Brumby]

if you see this
You get the idea more watts from the transmitting power (radar) the detection range will increase, the absolute size is the surface in squared meters, something that is fixed;

As I said you need to pay attention to what you post in support of what you say. Frankly I am starting to get tired of pointing out your mistakes. Please note your initial radar equation that you shared (post #1135) and your insistent that RCS is variable. You are now posting a new equation (presumably) that talks of a fixed absolute surface area. First, surface area and RCS are not the same thing (I hope you actually know this); and second you have changed the terms of discussion from RCS that is variable to surface area that is fixed. Can you please make up your mind and stick to it.

this tells you a MiG-21 will be detected at different ranges depending upon what radar paints it, but the angle and shape will affect the RCS but this last will be highly dependent upon the frequency.

Is there a point you want to make because they are not points of contention?

So in few words give me a better radar and i will see any stealth fighter, Sukhoi knows that, so they know speed and agility means life,

Your statement is deceptive. More favourable variables lower the threshold detection range. A better radar doesn't automatically mean detection. It must meet the threshold conditions.

therefore PAKFA`s designers opted for solutions that fans claim are unstealthy, but the Russians decided that since they have a smaller military budget and radar technology will catch up with stealth, it was better to go for super cruise and a very agile fighter, pretty much what Pierre Sprey says.
The Russians have another aircraft philosophy regarding the 5th generation fighters

That is a development path that the Russians chose to make. That is its prerogative.

 

[Air Force Brat]

As I said you need to pay attention to what you post in support of what you say. Frankly I am starting to get tired of pointing out your mistakes. Please note your initial radar equation that you shared (post #1135) and your insistent that RCS is variable. You are now posting a new equation (presumably) that talks of a fixed absolute surface area. First, surface area and RCS are not the same thing (I hope you actually know this); and second you have changed the terms of discussion from RCS that is variable to surface area that is fixed. Can you please make up your mind and stick to it.


Is there a point you want to make because they are not points of contention?


Your statement is deceptive. More favourable variables lower the threshold detection range. A better radar doesn't automatically mean detection. It must meet the threshold conditions.


That is a development path that the Russians chose to make. That is its prerogative.

All excellent arguments Mr. Brumby, although your last statement may have been thrust upon the Russians by their lack of success in reducing the L/O of their supposed 5th Gen aircraft. So they make a statement that covers that lack of success with a veneer of capability, hoping if they throw enough "stuff" on the wall, something will stick?

 

[Brumby]

All excellent arguments Mr. Brumby, although your last statement may have been thrust upon the Russians by their lack of success in reducing the L/O of their supposed 5th Gen aircraft. So they make a statement that covers that lack of success with a veneer of capability, hoping if they throw enough "stuff" on the wall, something will stick?

On the contrary I am actually assuming that the Russians will make progress and that they will be able to actualise a relatively stealthy plane. Under such a scenario, where both sides are offering stealthy airframes, the notion of WVR scenarios is a reasonable extension of that premise. As such the Russian's emphasis on ACM plus stealth as a total package seems reasonable at face value. However what is absent from B787's argument which I did not talk about is that in my view the US is pursuing spectrum domination as a strategy rather than simply stealth as a feature. The principle of first look first shot and first kill to me is still a constant. However stealth is just one component of the spectrum. Spectrum domination in my view covers RF, IR and Optical and the ability to bring together the whole spectrum into one highly situational aware platform that can dominate the battlespace. Although the Russians might eventually catch up on stealth, technologically they are probably two generations behind in avionics and optical IR. For example, the OLS-35 in the SU-35 is a non imaging cooled IRST system. In contrast, the world has moved on to scanning arrays as in PIRATE and in the even more advanced staring arrays as in the F-35. What that means is that even though stealth might limit radar detection to 40 nm, the fact that the US using other advanced non RF sensors will still dominate at BVR.

 

[b787]

As I said you need to pay attention to what you post in support of what you say. Frankly I am starting to get tired of pointing out your mistakes. Please note your initial radar equation that you shared (post #1135) and your insistent that RCS is variable. You are now posting a new equation (presumably) that talks of a fixed absolute surface area. First, surface area and RCS are not the same thing (I hope you actually know this); and second you have changed the terms of discussion from RCS that is variable to surface area that is fixed. Can you please make up your mind and stick to it.


.

My friend first present me an equation that says the power density will not affect the detection range and another equation that proves that the resonance (frequency related) basically does not render stealth useless.

The RCS is related to the absolute size of the target (it is the reflecting area) however the angle of the incidence of the Electromagnetic wave can affect the RCS depending in the frequency,

The target radar cross sectional area depends of:

• the airplane’s physical geometry and exterior features,
• the direction of the illuminating radar,
• the radar transmitters frequency,
• the used material types.

PAKFA has geometry managment such as planforming, the direction of illumination is dependent upon the route the Stealth aircraft chooses, the radar frequency are only a limited spectrum of most current radars use but most modern radars like NEBO use frequencies that render stealth useless

. General definition of Radar Cross-Section Technically Radar Cross-Section (RCS, or σ) is the ratio of radiated power density intercepted by a target to the power per unit solid angle backscattered to the receiving antenna by the target, so it is a measure of the efficiency with which a target echoes radar energy back to the radar receiver. This efficiency depends on shape, size, material composition and other factors that vary widely between different types of target. Therefore in order to compare dissimilar targets it is useful to express their efficiency in terms of the projected cross-sectional area of a perfectly conducting sphere which would return the same power to the same receiver in the same conditions. This equivalent area is the RCS and is expressed in square metres.

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the RCS of an aircraft increases as wavelength of the illuminating radar increases.

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[Brumby]

My friend first present me an equation that says the power density will not affect the detection range and another equation that proves that the resonance (frequency related) basically does not render stealth useless.

Why do I need to do that? I did not make any claims of such nature that I need to present evidence in support. You are a strange individual to have a conversation because although we might be exchanging views we are not talking because every reply you make is referencing to an evolved topic rather than actually replying.

The RCS is related to the absolute size of the target (it is the reflecting area) however the angle of the incidence of the Electromagnetic wave can affect the RCS depending in the frequency,

Isn't it obvious in order to have any RCS you need to have a physical object. In other words, you can't generate a RCS out of nothing. What is your point though?

PAKFA has geometry managment such as planforming, the direction of illumination is dependent upon the route the Stealth aircraft chooses,

I am sure PAKFA has features that you described. How is it connected to what we have discussed so far (at least related to the last few post)?

the radar frequency are only a limited spectrum of most current radars use but most modern radars like NEBO use frequencies that render stealth useless

Seriously I did not know NEBO makes stealth useless. How so?

 

[Epsilon]

The Russians have another aircraft philosophy regarding the 5th generation fighters

IMHO, they really don't.

it was better to go for super cruise and a very agile fighter, pretty much what Pierre Sprey says.

Just like with F-22. With their fighter US didn't go F-117 or flying wing route. They went back to 4th gen and adapted it to steath. Fighter is still a fighter, it needs agility and high speed, that's why a stealthier solution in flying wing was thrown away (YF-23 somewhat reminded a flying wing btw but they preferred YF-22 maybe partly because of higher agility through thrust vectoring?).
I don't see what is so really important and critical that T-50 lacks in comparison to F-22. Although I am zealously wanting to see how they will apply RAM (I am sure some think there will be no RAM).

 

[aksha]

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The final FGFA deal that is expected to be signed and worth $3.7 billion will involve the fly-in into India of three FGFA PAK FA aircraft for IAF to begin flying them and for TAC-D in Gwalior to begin writing the manual for tactics, etc., and the transfer of flight control laws and open[air]-frame design to enable ADA to modify the aircraft architecture to suit Indian requirements and source codes, including for the fire control system.

But where India’s procurement contracts are concerned, there’s always and inevitably a foul-up, the downside. There’s one in the FGFA agreement as well. The wondrously incomprehensible and myopic aspect of this deal is the rejection by IAF-MOD of Moscow’s extraordinarily generous offer to have its Saturn jet engine design bureau (that resulted from the merging of the Lyulka and Tumansky design bureaus) jointly with Indian counterpart (GTRE) develop a powerful new era jet power plant — something no other country will deliver on and, despite promises, certainly not the technology hyper-protective US. But, as reported elsewhere, India will instead buy the Saturn AL-41 engines whole to power the Indian-modified FGFAs!

 

[b787]

IMHO, they really don't.

Just like with F-22. With their fighter US didn't go F-117 or flying wing route. They went back to 4th gen and adapted it to steath. Fighter is still a fighter, it needs agility and high speed, that's why a stealthier solution in flying wing was thrown away (YF-23 somewhat reminded a flying wing btw but they preferred YF-22 maybe partly because of higher agility through thrust vectoring?).
I don't see what is so really important and critical that T-50 lacks in comparison to F-22. Although I am zealously wanting to see how they will apply RAM (I am sure some think there will be no RAM).

Latest picture of 051

PAKFA has stealth features but not to the level that these affect its maneuverability and speed

 

[antiterror13]

i beleive
the FGFA/ license production of PAK FA will happen
simply because the IAF has no other option

AMCA is expected only in 2030 ,( unlike LCA , IAF is giving the AMCA full back up even at the designing stage)

True, India has no other option, unless the US prepared to sell F-22 to India or China to sell its J-20

From Indian fighter development records (with all due respect) I highly doubt the AMCA would be operational in 2030 (if it even goes into operational at all), more likely in 2035-2040 and it would be way too late.

 

[TerraN_EmpirE]

IMHO, they really don't.

Just like with F-22. With their fighter US didn't go F-117 or flying wing route. They went back to 4th gen and adapted it to steath. Fighter is still a fighter, it needs agility and high speed, that's why a stealthier solution in flying wing was thrown away (YF-23 somewhat reminded a flying wing btw but they preferred YF-22 maybe partly because of higher agility through thrust vectoring?).
I don't see what is so really important and critical that T-50 lacks in comparison to F-22. Although I am zealously wanting to see how they will apply RAM (I am sure some think there will be no RAM).

Latest picture of 051

PAKFA has stealth features but not to the level that these affect its maneuverability and speed

I kinda agree epsilon but i also kinda agree with B747 yet in the end I kinda don't agree.
When the USAF issued the ATF competition they were offered a wide range of concepts from tailless fighters to conventional options. Two the YF22 and YF23 were chosen for development. The two choices hat twin tails and very good performance numbers. The YF23 favored stealth, pelican tails over the jet exhaust. YF22 favored flight performance. The choice was made the decision involved extensive modifications to the YF22. But the end product the F22A was designed as the most maneuverable fighter of the world at the time.
It was designed to favor internal weapons for both performance and stealth. And as originally conceived with three radar systems.
The PAK FA was designed after the Raptor, it used lessons learned from the ATF. Despite claims to the contrary it was designed along the same lines but with slightly more emphasis placed on maneuver. These are not fourth generation fighters turned stealth, they are stealth machines from the start with there most cutting edge technologies available to there builders. They were designed based on the choices of comprises. Sensors vs aero vs lethality. Pak fa has the edge of timing, it built on what raptor set. And J20 is the same. But that doesn't mean that they are inherently superior. Each is based on the choices made by there designers.