FLIR , IRST in air to air mission

Cockpit, radar, helmet-mounted display, and other avionics
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BDF

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Unread post16 May 2020, 03:03

ricnunes wrote:The thing is, even the Russians admit that their Su-57 has an RCS of 0.1 to 0.5 square meters (no, that's not a typo). Another evidence of this was the fact that the Indians bailed out as partners of the PAK-FA/Su-57 program and the main reason seem to have been that the aircraft didn't have an RCS nearly as low as the Indians expected.
And the experience that the Chinese have in designing LO/VLO aircraft is similar if not smaller compared to the Russians. Of course that the Chinese have access to vast amounts of resources/cash which should give them an edge over the Russians. As such I believe that the Chinese aircraft (J-20/J-31) will be better - RCS speaking - than the Russian SU-57 but definitely not so good as the American designs (F-35 and F-22). And -30 dBsm range (around 0.001 square meter) for the Chinese aircraft would put them very close to the F-35 for instance, this in terms of RCS.
Hence why I put the Chinese in the range of 0.01-0.05 square meters in terms of RCS.


I'm not convinced that one can cross compare the two countries' capabilities in that manner nor do we fully understand program goals for LO for the Su-57 or J-20. There is no real concrete information related to how much, if any technological sharing that has gone on, nor do we have any real info Chinese LO research programs. We do know that they've be notorious in the past in their espionage efforts and have apparently had quite some success, though its not clear how deep they've been able to get into special access programs and data. The Raptor and its LO systems are 20 years old, its not at all inconceivable that during that time they've been able to rapidly advance their LO technology base, probably aided by espionage.

Obviously, its impossible to estimate RCS by looking at an airplane, but certainly the J-20 looks from a fit and finish perspective far more advanced LO wise than the Felon. It could be just a dressed up pig, or it could be very capable. Speculation is all over the place. There is nothing concrete available in public sources. From my perspective I think its dangerous to assume that its -20 to -27dBsm difference in optimal RCS from US types. That doesn't mean I believe that it (the J-20) is as complete and sophisticated signature wise as the Raptor or Lightning. In fact, my guess is that it probably is in the -25 to -30dBsm range over the frontal arc in higher frequencies but is significantly inferior off aspect and to lower frequencies. My hope is that it's exploitable by our sensors and networks. I also hope that I'm wrong, but I'm not sure I am.
When it comes to fighting Raptors, "We die wholesale..."
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Unread post16 May 2020, 15:51

BDF wrote:I'm not convinced that one can cross compare the two countries' capabilities in that manner nor do we fully understand program goals for LO for the Su-57 or J-20.


When I previously said that the Chinese had similar experience as the Russians is designing LO/VLO aircraft, I was actually proposing a "best case scenario" for the Chinese because in terms of experience in designing LO/VLO aircraft the Russian should have an edge since they have been trying to design such aircraft since the 1980's, being the Mig 1.44 one of such examples. On the other hand, it's obviously that the Chinese have far more money and resources than the Russians and this will inevitably help offset the gap in terms of experience in designing LO/VLO aircraft hence why I mentioned in my previous post that the Chinese and Russians should have similar capabilities in this field (LO/VLO aircraft).

And all of this just not to mention the much more vast experience by the Russians in designing aircraft and engines than the Chinese. One can 'accuse' the Russians of many things but not being able to design aircraft and engines isn't definitely one of them. As opposed the Chinese aren't even able to properly design an engine (they build licenced-build Russian engines).


BDF wrote:There is no real concrete information related to how much, if any technological sharing that has gone on, nor do we have any real info Chinese LO research programs. We do know that they've be notorious in the past in their espionage efforts and have apparently had quite some success, though its not clear how deep they've been able to get into special access programs and data.


IMO, it's very hard to conceive that the Chinese may suddenly be able to fully manufacture stealth aircraft just because they were able to hack some computer files from US military/defence computers.


BDF wrote:The Raptor and its LO systems are 20 years old, its not at all inconceivable that during that time they've been able to rapidly advance their LO technology base, probably aided by espionage.


And supersonic jet fighters are more than 60 years old and yet most countries in the world aren't able to design such aircraft by themselves, let alone design supersonic jet fighters that can be similarly capable as the best currently existing supersonic jet fighters from experienced nations.

As such and IMO it's a bit inconceivable that the Chinese can 'suddenly' build a stealth jet fighter which a RCS almost as low as the F-35 and this basically in the Chinese first attempt at designing and building such aircraft.
'Experience' has a "strength of it own" which surpasses by far any information gathered by cyber-espionage and does offset vast amounts of money.


BDF wrote:Obviously, its impossible to estimate RCS by looking at an airplane, but certainly the J-20 looks from a fit and finish perspective far more advanced LO wise than the Felon.


I trend to disagree. While I do agree that the J-20 has a better/lower RCS than the Su-57, the J-20 has some "less stealthy" features compared to other stealth aircraft and even compared to the Su-57. For instance, canards! While it is somehow accepted that canards may not degrade RCS in the exact frontal arc (when directly facing the radar source) canards inevitably affect RCS negatively (increase RCS) when not directly facing the radar source - for example when faced something like 30º of to the left or right (or up or down) from the radar source, the canard equipped aircraft will have it's RCS increased by much (compared to if canards were not present).
IMO, it's by no mere chance that none of the US stealth aircraft ever had canards. For instance one of the early JSF designs/proposals had canards but the final aircraft never had them. In this regard, the Su-57 actually has an advantage over the J-20 since the Su-57's "canard style" surfaces are well blended with the wing.
Another disadvantage of the J-20 RCS-wise is having more surfaces sticking out from the fuselage compared to other aircraft. I'm talking about those 2 ventral surfaces which I would suspect that shouldn't be that good for RCS:
Image

And then we have the Indian Air Force (IAF) claims that I also and previously mentioned.
So and like a puzzle put together, all of this leaves me to reach the conclusion which I've been stating here.

Of course and again, I believe that the J-20 has a lower/better RCS than the Su-57 because the Chinese have more money and better resources to improve the design, to have better manufacturing quality and access to better RAM materials but then again and due to what I've stated above, I don't believe that the J-20 has a "that much lower" RCS compared to the Su-57.



BDF wrote:It could be just a dressed up pig, or it could be very capable.


My "life experience" tells me that such things (unknown projects with questionable capabilities) as well as most other things in life are usually if not always somewhere in between and never either a "dressed up pig" or a "it could be very capable" which IMO somehow concurs with what I've been saying about the J-20 here.
“Active stealth” is what the ignorant nay sayers call ECM and pretend like it’s new.
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Unread post16 May 2020, 16:56

Nobody willing to talk seems to know the real reason why neither US nor Russia like tails over canards. To me it seems to be a service level preference, since designers in both countries show a perennial enthusiasm towards stealthy canards -- remember, X-36 was a VLO canard demonstrator, and both the original Lockheed JAST and the Yakovlev MFI were similar LO canard designs not far off from the J-20 configuration.

I wonder if the real reason is something mundane sounding that isn't directly related to fighting capabilities and is only appreciable after operating lots of aircraft for a long time. China has no shortage of access to paper theory, but they lack operational experience compared to the US and Russia. I wouldn't be surprised if they went with the thing that sounds better ("1 degree more ITR") over the thing that works out better ("greater control responsiveness at landing configuration").
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Unread post16 May 2020, 23:37

ricnunes wrote:For instance, canards! While it is somehow accepted that canards may not degrade RCS in the exact frontal arc (when directly facing the radar source) canards inevitably affect RCS negatively (increase RCS) when not directly facing the radar source - for example when faced something like 30º of to the left or right (or up or down) from the radar source, the canard equipped aircraft will have it's RCS increased by much (compared to if canards were not present).


An issue with canards in releation to signature is their usual placement, for instance the Eurocanards, in a different plane than the wing. This presents two sources for reflections, for instance in the forward and rear sector: The wing and canard. It's the same with traditional wing-tails. This configuration is to optimise aerodynamics, but not good for stealth. Stealth planes, like the J-20 and early JSF concepts, have canards in the same plane, meaning a single source for reflections. The canard partly masks the wing and, likewise, the tails on the F-22 and F-35 do something similar. And having all the surfaces in the same plane means you can crucially keep the overall planform alignment. The Swede's novel Z-form patent for a notional stealthy Gripen-like concept some years ago sought a compromise between signature and aerodynamics. Either way, by the time the canards - or tails- need to move too much you are likely going into a WVR fight where RF signature is not that important.

Why did the JSF ditch the canard? From the records it's known that tails were favored for carrier approach performance on the C-model. And if I remember correctly the Navy's requirement for a larger weapons bay holding 2000 lbs weapons also complicated a canard configuration. But there was probably a host of other factors that played in on the design change.

It is also interesting that the actuator fairings on the J-20 are canted. We don't see that on the F-22 or SU-57. The F-35A/B, of course, doesn't have protruding actuator fairings at all and the ones on the F-35C outboard wing are really flush.
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Unread post16 May 2020, 23:57

hornetfinn wrote:However I bet that EOTS could be used for cued search with narrowest FoV for really impressive range but naturally the search area will be extremely small. But could still be useful in some situations.


Very likely as the EOTS certainly has an air-to-air capability:

https://www.lockheedmartin.com/en-us/pr ... -eots.html

The Electro-Optical Targeting System (EOTS) for the F-35 Lightning II is an affordable, high-performance, lightweight, multi-function system that provides precision air-to-air and air-to-surface targeting capability.
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Unread post19 May 2020, 00:15

energo wrote:Why did the JSF ditch the canard? From the records it's known that tails were favored for carrier approach performance on the C-model. And if I remember correctly the Navy's requirement for a larger weapons bay holding 2000 lbs weapons also complicated a canard configuration. But there was probably a host of other factors that played in on the design change.


It's not only the JSF program that had an early concept with canards.

The ATF program (the resulted in the F-22) and the winner company of that same program (Lockheed) and manufacturer of the F-22 also had an early concept with canards. Here:
Image

As such I strongly believe that there is something "inherently wrong" with canards and lower/lowest RCS. Yes, I believe it's possible to somehow help to mitigate the negative effects of canards on RCS with some design measures but none of them seems to reach the same level as not having canards at all. The fact is that none of the stealth aircraft ever designed today did have canards (with the sole exception of the J-20 whose VLO capabilities are at best, questionable).
“Active stealth” is what the ignorant nay sayers call ECM and pretend like it’s new.
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Unread post20 May 2020, 00:52

ricnunes wrote:The ATF program (the resulted in the F-22) and the winner company of that same program (Lockheed) and manufacturer of the F-22 also had an early concept with canards. Here:


Actually, this and other artist impressions of the early ATF - which appeared widely in public literature - stems from the DoDs efforts in the 80s to confuse the public (read: Soviets) about the exact details of stealth. It was deliberately made to mislead as was the famous F-19 model by Testor.
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Unread post21 May 2020, 12:56

energo wrote:
ricnunes wrote:The ATF program (the resulted in the F-22) and the winner company of that same program (Lockheed) and manufacturer of the F-22 also had an early concept with canards. Here:


Actually, this and other artist impressions of the early ATF - which appeared widely in public literature - stems from the DoDs efforts in the 80s to confuse the public (read: Soviets) about the exact details of stealth. It was deliberately made to mislead as was the famous F-19 model by Testor.


Independently if the above is simply an 'artistic impression' or an actual concept, below you have an actual list of several proposals for the ATF program:
Image

As you can see, the majority of those ATF concepts actually had canards.
“Active stealth” is what the ignorant nay sayers call ECM and pretend like it’s new.
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Unread post21 May 2020, 13:06

That Rockwell tailless looks a lot like the early windtunnel tests of the T-10 (Su-27) program.
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Unread post22 May 2020, 15:32

energo wrote:
ricnunes wrote:The ATF program (the resulted in the F-22) and the winner company of that same program (Lockheed) and manufacturer of the F-22 also had an early concept with canards. Here:


Actually, this and other artist impressions of the early ATF - which appeared widely in public literature - stems from the DoDs efforts in the 80s to confuse the public (read: Soviets) about the exact details of stealth. It was deliberately made to mislead as was the famous F-19 model by Testor.


You really think the gov't was working with Testors to "throw" the Soviets off? That sounds like a real stretch, although I suppose it's within the realm of possibility.

I was always under the impression Testors came up with that design independently, i.e. without any help from the gov't. It was a nice stab at it IMO, given the available public information at the time. They had the engines about right (non-afterburning F-404's), weapons load (2, 2,000lb class weapons) and simple laser rangefinder in the nose.

Yes, everything else was wrong but hey, you have to start somewhere. Given what their Soviet "Ferret" stealth bird looked like though, I would hope nobody at Testors would own up to that, LOL.
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Unread post26 May 2020, 02:53

ricnunes wrote:IMO, it's very hard to conceive that the Chinese may suddenly be able to fully manufacture stealth aircraft just because they were able to hack some computer files from US military/defence computers.


ricnunes wrote:And supersonic jet fighters are more than 60 years old and yet most countries in the world aren't able to design such aircraft by themselves, let alone design supersonic jet fighters that can be similarly capable as the best currently existing supersonic jet fighters from experienced nations.

As such and IMO it's a bit inconceivable that the Chinese can 'suddenly' build a stealth jet fighter which a RCS almost as low as the F-35 and this basically in the Chinese first attempt at designing and building such aircraft.
'Experience' has a "strength of it own" which surpasses by far any information gathered by cyber-espionage and does offset vast amounts of money.


I would agree if it were limited to simply cyber espionage. The problem is that Chinese espionage activities have gone far beyond this. They have been very active in technological as well as industrial espionage for decades. There are several interesting (and troubling) articles in the various defense think tanks out there that discuss this very problem. Their espionage efforts undoubtedly are aiding their domestic programs. This is one reason why drawing comparisons to Russian efforts is almost meaningless. Yes, they lag in certain areas but are ahead in others. Given their resources they will not be behind Russia for very long in any technical field IMO.

ricnunes wrote:I trend to disagree. While I do agree that the J-20 has a better/lower RCS than the Su-57, the J-20 has some "less stealthy" features compared to other stealth aircraft and even compared to the Su-57. For instance, canards! While it is somehow accepted that canards may not degrade RCS in the exact frontal arc (when directly facing the radar source) canards inevitably affect RCS negatively (increase RCS) when not directly facing the radar source - for example when faced something like 30º of to the left or right (or up or down) from the radar source, the canard equipped aircraft will have it's RCS increased by much (compared to if canards were not present).
IMO, it's by no mere chance that none of the US stealth aircraft ever had canards. For instance one of the early JSF designs/proposals had canards but the final aircraft never had them. In this regard, the Su-57 actually has an advantage over the J-20 since the Su-57's "canard style" surfaces are well blended with the wing.
Another disadvantage of the J-20 RCS-wise is having more surfaces sticking out from the fuselage compared to other aircraft. I'm talking about those 2 ventral surfaces which I would suspect that shouldn't be that good for RCS:


While it is true that no design has made it to production there were programs that did utilize canards. For instance, the Northrop NATF proposal did. I don’t disagree that canards are not optimal but you have to take this airplane’s ConOps into account. The J-20 does not appear to focus on deep penetrating OCA or strike missions but rather seems aimed directly at attacking HVAA and fighting at the periphery of the A2/AD bubble. In that regard, I do not think we fundamentally disagree on the idea that off frontal aspect RCS is worse (perhaps significantly worse) than US designs. As I stated earlier, my guess is that frontally the J-20 is in the -20 to perhaps -30dBsm range. Side and rear aspect I’m positive are inferior to US designs.

ricnunes wrote:And then we have the Indian Air Force (IAF) claims that I also and previously mentioned.
So and like a puzzle put together, all of this leaves me to reach the conclusion which I've been stating here.

Of course and again, I believe that the J-20 has a lower/better RCS than the Su-57 because the Chinese have more money and better resources to improve the design, to have better manufacturing quality and access to better RAM materials but then again and due to what I've stated above, I don't believe that the J-20 has a "that much lower" RCS compared to the Su-57.


Problem is that anecdotes like these are meaningless without context. We’re the J-20’s operating with their Luneberg lenses? Were the Indians able to build an engagable track on the J-20s? How did they even know it was a J-20? Can we even believe the Indian claim at all? This is right up there with the Chinese claims of tracking F-22s off the coast of Japan and South Korea. We don’t know how the F-22s were operating and how they were flying relative to said radar.

ricnunes wrote:My "life experience" tells me that such things (unknown projects with questionable capabilities) as well as most other things in life are usually if not always somewhere in between and never either a "dressed up pig" or a "it could be very capable" which IMO somehow concurs with what I've been saying about the J-20 here.


Ha, well my comment wasn't meant to be a binary postulation... My hope is that I'm wrong in this, but from what I've read coming from defense circles doesn't give me a warm and fuzzy feeling about this threat. Back to the original discussion, my concern is how our "kill web" will be able to detect and cue appropriate sensors with enough lead to time to enable first shot opportunities. Even if the worst case scenario is a -20dBsm frontal RCS that would imply a ~40nm detect range by the APG-77. If the J-20 was cruising at M 1.5 and the Raptor was high subsonic, that's just under 2 min until a merge. Worse if they're bother supersonic. Its a challenging problem and I hope we're on top of it.
When it comes to fighting Raptors, "We die wholesale..."
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Unread post26 May 2020, 16:57

BDF wrote:I would agree if it were limited to simply cyber espionage. The problem is that Chinese espionage activities have gone far beyond this. They have been very active in technological as well as industrial espionage for decades. There are several interesting (and troubling) articles in the various defense think tanks out there that discuss this very problem. Their espionage efforts undoubtedly are aiding their domestic programs. This is one reason why drawing comparisons to Russian efforts is almost meaningless. Yes, they lag in certain areas but are ahead in others. Given their resources they will not be behind Russia for very long in any technical field IMO.


I would never call the Russian espionage meaningless compared to the Chinese espionage. The Russians traditionally use major espionage efforts in order to get hold to industrial secrets from other nations, namely from the USA which more recently also includes cyber espionage. One can argue that during the Cold War when USSR existed that such espionage efforts (lead by the KGB) were apparently stronger compared to nowadays but I believe this may or could be a 'perception' instead of a real fact. Examples such as the assassination/poisoning of Alexander Litvinenko in London and other similar episodes clearly proves that the Russian espionage is very much active and not necessarily any less so compared to the Chinese nowadays.
Moreover if any reduction of 'in-field' espionage by the Russians compared to the old days of the Soviet Union actually occurred than I'm pretty sure that this was more than offset by (Russian) cyber espionage.

And even looking at the old days of the USSR/KGB which had an extensive and extremely effective espionage network note that even with all these effective efforts that the USSR never managed to nearly reach the level of technological advances that the USA had and still has. And what do I mean with this?
What I mean is that, it takes much more than extensive and extremely effective espionage efforts to be able to build something extremely advanced such as a stealth aircraft. Heck, even with all the Chinese also extensive and effective espionage efforts they don't seem to be able to design 'simpler stuff' such as a Jet engines for supersonic/fighter aircraft.

The principle of all of this is IMO quite straightforward:
- Imagine for example that you get your hands on the world's best cuisine recipes. This alone doesn't make you the world's best chef, doesn't it? It doesn't even make you a good chef. Heck, it doesn't even make you an average cook!

My point is that there's lots of other stuff (secrets) that only vast experience and knowledge can bring you and which NO 'recipe' alone will ever bring or give you. What I'm trying to say is that the secrets that the Chinese may have get their hand on are at best 'good recipes' which together with great deals of money gives the Chinese the ability to build an average LO almost VLO aircraft but nothing close to the VLO aircraft build by the Americans such as the F-22 or F-35.


BDF wrote:While it is true that no design has made it to production there were programs that did utilize canards. For instance, the Northrop NATF proposal did. I don’t disagree that canards are not optimal but you have to take this airplane’s ConOps into account.


Let me give you another example that canards and stealth doesn't 'mix well':
- As I believe we all know, the Europeans have been 'in love with' canards. The French Mirage 2000 and Rafale, Swedish Viggen and Gripen, the British design that was the 'ancestor' of the Gripen (forgot its name) and the British Aerospace EAP, the Eurofighter Typhoon are examples of this. But if we look at the European efforts in developing a 5th gen fighter aircraft, namely the Franco-German NGF and the British Tempest what do they have in common? They don't have canards :wink:

BDF wrote:The J-20 does not appear to focus on deep penetrating OCA or strike missions but rather seems aimed directly at attacking HVAA and fighting at the periphery of the A2/AD bubble. In that regard, I do not think we fundamentally disagree on the idea that off frontal aspect RCS is worse (perhaps significantly worse) than US designs. As I stated earlier, my guess is that frontally the J-20 is in the -20 to perhaps -30dBsm range. Side and rear aspect I’m positive are inferior to US designs.


I wouldn't rule out that the J-20 is also planned for missions such as deep penetrating OCA or other strike missions. Yes, it won't have the same capability to hide from enemy air defences like the F-35 or F-22 do but their reduced RCS gives it a much better survivability compared to other aircraft dedicated to such roles such as the Su-24 or Su-34.
The 'massive size' of that thing (J-20) means or could mean that it carries big amounts of fuel which by its turn means long range which could end up being comparable to again the Su-24 or Su-34. So if aircraft like the Su-24 or Su-34 have as their main role, deep penetrating OCA or other strike missions then I strongly believe that the J-20 can also perform such roles (and again better or having a better survivability compared to the Su-24 or Su-34).

However I generally agree with you that the J-20 could be used together with some very long-range air-to-air missiles against HVAA.
IMO, I believe that the J-20 main role is being a long range interceptor. I imagine it like a sort of a stealthy Mig-31. Or more precisely I imagine it like a stealthy combination of a Mig-31 with a Su-34.
But then again I don't think that frontally the J-20 RCS is in between the -20 to -30dBsm range. IMO, I think that in the best case scenario the J-20 frontal RCS is -20dBsm (or 0.01 square meters).
The following article seems to concur with my let's say, 'assessment':
https://www.realcleardefense.com/articl ... 12550.html

where one can read for example:
Like the Russian Pak FA, the J-20 apparently lacks some attributes of a 5th generation fighter.


The J-20 has been characterized as having medium stealth with its best performance from the front and the worst from the rear. Business Insider quotes a senior scientist at Lockheed Martin as saying, “It’s apparent from looking at many pictures of the aircraft that the designers don’t fully understand all the concepts of LO [low observable] design.”


And perhaps even more interestingly:
Current Air Force Chief of Staff General David Goldfein has compared the J-20 to the F-117, which reportedly had a radar cross section of .269 square feet.


A radar cross section of .269 square feet is around 0.02 square meters (or around -20dBsm) which is within or around the values that I've be taking about here.


BDF wrote:Problem is that anecdotes like these are meaningless without context. We’re the J-20’s operating with their Luneberg lenses? Were the Indians able to build an engagable track on the J-20s? How did they even know it was a J-20? Can we even believe the Indian claim at all? This is right up there with the Chinese claims of tracking F-22s off the coast of Japan and South Korea. We don’t know how the F-22s were operating and how they were flying relative to said radar.


Yes, I fully agree with you above!
However that 'Indian claim' seems to be more or less 'in-line' with everything else that have been said about the J-20 and it's stealth capabilities. BTW, this was the only reason why I posted that 'Indian claim'.
But yeah, again I agree that Indian claims alone or by itself doesn't prove squat about the J-20 stealth capabilities.



BDF wrote:Even if the worst case scenario is a -20dBsm frontal RCS that would imply a ~40nm detect range by the APG-77. If the J-20 was cruising at M 1.5 and the Raptor was high subsonic, that's just under 2 min until a merge. Worse if they're bother supersonic. Its a challenging problem and I hope we're on top of it.


Well, like I mentioned above the -20dBsm frontal RCS for the J-20 seems to be a best case scenario instead of being a worse case scenario.
But lets use your example that a APG-81 or APG-77 radar can detect an incoming J-20 at a range of 'only' 40 nautical miles.
40 nautical miles is 74 km which for sure isn't by any measure a small range/distance.
Actually and currently aircraft like the F-15 or F-16 don't seem to be able to engage other fighters in BVR at such distances (40nm). 4th gen aircraft engage other fighter aircraft at lower ranges than that - I would say lower than 30nm is the norm. All fighter vs fighter BVR engagements that ever occurred until today seem to confirm this 'norm'.
This seems to be due a combination of BVR missiles 'effective range' or more precisely NEZ and the difficulty of radars to detect fighter-sized aircraft at distances lets say superior to 40nm. Of course that better missiles such as the AIM-120D or Meteor and better radars such as the upcoming AESA radars for instance will increase the usual BVR engagement ranges but then again aircraft with reduced RCS (such as the J-20) will offset the advances of better (higher range) missiles and radar technology.

So and bottom line: I'm convinced that the F-22 and F-35 will maintain the superiority over the J-20 due to a combination of better stealth together with better sensors (even 'using' the radar as the 'only' sensor). They will still be able to engage enemy J-20's at similar ranges (if not higher) that aircraft like the F-15 and F-16 engaged Migs in the recent past and this without the J-20 being able to counter-detect the F-22 or F-35. However such engagement will be somehow more challenging to a F-35 or F-22 compared to fighting against 4th or 4.5th gen fighter aircraft since these aircraft can indeed be engaged at much longer ranges than what was previously possible.
Resuming, the F-22 and F-35 will still have the first look, first shot and first kill against the J-20. Now of course if you're flying a 4th or 4.5th gen fighter aircraft like the F-15, F-16, Super Hornet, etc... then you would definitely be in a big trouble against a J-20.


Sorry for the long post...
“Active stealth” is what the ignorant nay sayers call ECM and pretend like it’s new.
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Unread post27 May 2020, 19:31

ricnunes wrote:I would never call the Russian espionage meaningless compared to the Chinese espionage.... (Snip for brevity)


Indeed the Soviets and now the Russians have had (unfortunately) quite successful espionage programs. The Soviets were quite hamstrung by their economic handicaps and were never even competitive quite frankly. I think at their best they were at was something like 40% of the U.S.’s GDP and were never a manufacturing powerhouse that China is. China has already surpassed us in PPP and will surpass us in the 2030s in raw GDP. I just do not see how you can compare the two and extrapolate capabilities this way. Certainly, white papers on China do not paint a very pretty picture on this issue. I’m inclined to look at this pessimistically unless concrete information supports otherwise.


ricnunes wrote:Let me give you another example that canards and stealth doesn't 'mix well':
- As I believe we all know, the Europeans have been 'in love with' canards. The French Mirage 2000 and Rafale, Swedish Viggen and Gripen, the British design that was the 'ancestor' of the Gripen (forgot its name) and the British Aerospace EAP, the Eurofighter Typhoon are examples of this. But if we look at the European efforts in developing a 5th gen fighter aircraft, namely the Franco-German NGF and the British Tempest what do they have in common? They don't have canards :wink:


The Chinese have a certain affinity for the canard-delta configuration. Its been in their design evolution since the J-8 in the mid ‘70s. So, it’s not surprising that they went this direction. There are certainly drawbacks to this configuration from at low observables standpoint. But it is not clear how much and how this relates to future LO aircraft designs. Certainly, future designs will need superior broad-band LO than current 5th Gen designs. So, I don’t find it surprising that they (Euro programs) aren’t going in the direction. That being said, programs like the Tempest and FCAS are probably not showing their actual designs but rather notional mockups for publicity purposes. I suspect that they’ll will go “tailless” designs like we see for our NCAD/PCA notional designs. So, I’m not sure comparing future notional designs to current 5th gen Chinese designs is really worth it. They have different LO objectives.

ricnunes wrote: (Snipped for brevity again)
But then again I don't think that frontally the J-20 RCS is in between the -20 to -30dBsm range. IMO, I think that in the best case scenario the J-20 frontal RCS is -20dBsm (or 0.01 square meters).
The following article seems to concur with my let's say, 'assessment':
https://www.realcleardefense.com/articl ... 12550.html

where one can read for example:
Like the Russian Pak FA, the J-20 apparently lacks some attributes of a 5th generation fighter.


The J-20 has been characterized as having medium stealth with its best performance from the front and the worst from the rear. Business Insider quotes a senior scientist at Lockheed Martin as saying, “It’s apparent from looking at many pictures of the aircraft that the designers don’t fully understand all the concepts of LO [low observable] design.”


And perhaps even more interestingly:
Current Air Force Chief of Staff General David Goldfein has compared the J-20 to the F-117, which reportedly had a radar cross section of .269 square feet.


A radar cross section of .269 square feet is around 0.02 square meters (or around -20dBsm) which is within or around the values that I've be taking about here.


I think Gen. Deptula’s comments are in line with my thinking; as are Tirpak’s comments. It is interesting that Gen. Goldfein’s comparison to the F-117. I realize that the AFA’s article relates to at 0.269 ft² RCS, which converts to -16 dBsm signature, but its been widely reported that the F-117’s signature is closer to the -30 dBsm range. AvWeek has it at -35 dBsm for instance. Given that in Ben Rich’s book on skunk works he was discussing how he’d pitch the F-117 to Air Force brass by rolling marble sized ball bearings across their desk suggest strongly to me that the -30 dBsm figure is probably the more accurate estimate. They arrived at this estimate by literally gluing different sized ball bearings on the test article on the range to see when the aircraft had a bigger signature than the bearing.

I’m less worried about the platform vs platform side of things but more concerned on how our network will enable early detections to run intercepts with sufficient stand off ranges to protect HVA and enable us to push deeper into any A2/AD bubble. I’m not sure that networked 5th gen fighters is the answer alone. 40-50nm detection ranges, even if true, are problematic because that is a small search volume compared to say 115+ ranges with the -77/81s. Given that this thing is supposed to supercruise (with a ton of gas to do it) it could lead to very short reaction times and potentially failed intercepts.
When it comes to fighting Raptors, "We die wholesale..."
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Unread post28 May 2020, 15:01

You may have a point here, however...

They're clearly doing stealth vs. stealth work in the western US/Pacific/elsewhere. That seems to be in the form of the F-117 today, but I'm sure they've also conducted plenty of Raptor vs. Raptor extreme high mach closing speek intercepts. And we know a dedicated F-35 aggressor squadron is only a short time away.

This is undoubtedly happening not just in the F-22/35 community, but our 4th gens as well. The SH Block III's podded IR sensor (and the USAF's equivalent on F-15C's) has been in play for some time now, at least testing wise. I'm sure they'll have those intercepts optimized in short order, if they haven't already done so.

And soon, with AIM-260 they'll get something that gives them what they really need.... more time during said intercepts. The whole scenario isn't without precedent (minus the stealth): They've been doing intercepts using drones mimicking Foxbat/Foxhound closing speeds forever, going back to the F-14/Phoenix.

BOTTOM LINE: They've got the data necessary to pull it off IMO..
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Unread post29 May 2020, 14:32

The 3rd disadvantage listed is very interesting for me. If I'm understanding this correctly you can only configure it for high lift or low drag but not both.

The EF Typhoon's design seem to be high lift and simply uses brute power to compensate for the drag.
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