So given the 3 decent sources presented showing that RCS increase is no-where near 100x going from 10Ghz down to 1Ghz being pushed by a few who were confused by some maths. I guess we can conclude that the ~80nm frontal detection range by the A-50 against the F-35 in the simulation is not so obscene at all. As mentioned by the person who ran the sim, 80nm is not enough for the AEW aircraft to be relevant to the stealth vs target engagement unless doctrine gets updated to put AEW aircraft right up on the front line, which would be an unwise option.

A stealth fighter just needs to make sure to keep the AEW aircraft somewhere in its forward 60 degree arc as it approaches it targets which should be quite a distance away from the AEW plane. Given a 290nm buffer for the stealth aircraft to get themselves into position, this shouldn’t be too difficult.

Of course the AEW support argument is entirely moot if the defending side doesn’t have enough of them to go around which is the case for all nations but one.

It would be good if someone with a bit of insight could throw in their $0.02 on how a legacy aircraft is going to operate in future against stealth threats. So far a couple of attempts at the new doctrines have been pretty lacking in creativity and thought:

– All legacy aircraft will now fly at low level in small groups, hoping that small, defensive jammers designed to thwart tiny missile radars will mask their radar signatures against the world’s most mature fighter radar to a level never before claimed by any military in the world, even against legacy radars.
– Another person said that no aircraft, whether legacy or stealth will ever fly in a wide formation. All engagements are tight format vs tight formation, no exceptions, even when it is overwhelmingly a better tactic for stealth aircraft to engage enemies from multiple directions at once. Despite images like this appearing on certain manufacturer promotional material:

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So how do YOU operate your forces against an enemy weapons system that sees you first from a LONG way away, is most likely going to get the 1st shots in a head to head engagement but can select its approach angle to increase its advantage, is going to have time to call in plenty of backup before engaging you without allowing you the same opportunity, but can’t turn quite as well or can’t run away for too long if you chase them.

What formations do you fly as a normal routine, what spacing, altitude, speed, sensor profile (all/some active/passive)? Assume your goal is to ensure air dominance over neutral territory to keep it simple. Diagrams will be even more helpful so we can model this thing.

From Electromagnetic Wave Scattering by Aerial and Ground Radar Objects
Professor Oleg I. Sukharevsky. 2015.
https://www.crcpress.com/Electromagnetic-Wave-Scattering-by-Aerial-and-Ground-Radar-Objects/Sukharevsky/9781466576780

Comparison of various aircraft RCSs at 10GHz and 1GHz using multiple RCS solvers.

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…and a couple VLO targets…

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From Computer Simulation of Aerial Target Radar Scattering, Recognition, Detection, and Tracking
Professor Yakov D. Shirman. 2001.
http://www.amazon.com/Computer-Simulation-Scattering-Recognition-Detection/dp/1580531725

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Predator drone RCS provided by eField RCS simulation software (an RCS solver that uses multiple, correlated solving algorithms to process RCS of models) brochure showing a certain aspect of the drone at 3GHz and 10GHz with little difference in RCS.

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What can be seen in the results of these tests is that the impact of low band radar is only really pronounced at angles at a normal to the large leading edges of aircraft, such as their wing leading edges (most visible with the B-2 example). Frontal RCS seems to be impacted minimally. That being the case, then there would be a very wide arc in the F-35’s frontal aspect which would only be moderately impacted by low frequency radars. An increase in RCS of 3-5 times (in Msq) only results in an increase in detection range of 31%-49%.

I think it would be a career limiting mistake for anyone responsible for making decisions on doctrine to assume current stealth aircraft have no technology in place to handle long waves.

Typical CNT infused, polymeric RAMs rumored to be used on aircraft surfaces work by matching the impedance of air at the Air->Material interface, preventing the EM energy from simply bouncing off the surface. They then allow the electrical current to pass through the CNT infused “matching” layer to the Matching Layer->Conductive Substrate interface where the energy is absorbed by the substrate. About 5 studies I’ve read have shown that for 10GHz’ish, the most effective thickness (the “matching thickness” where absorption can peak to better than -60dB over a tiny bandwidth) for those particular CNT/polymer RAM “recipes” is around 2.5-3.5mm. There’s a misconception that this RAM needs to be 1/4 of the target wavelength in thickness to be effective. This is not the case with the CNT, matching layer RAM. This type of RAM is very frequency specific, has a pretty low -10dB bandwidth and typical application on fighters would be to target fire-control and missile radar frequencies.

The other type of RAM is the deep channel RAM seen on the outer edges on all current US stealth aircraft. With a very sharp leading edge, similar to the pyramidal shaped RAM used to line the walls of anechoic chambers, this RAM has a greater depth in relation to the incident EM waves (greater than 6 inches on fighter leading edges) and will create a very gradually increasing impedance over a greater distance which will be effective over a far wider frequency range. Assuming there’s no EM “magic” being done with the sharpened leading edge shape and RAM for multiple frequencies would be incredibly naive.

Then there’s this. I’ve seen this on a number of photos (the F-22 looks the coolest science-wise when it’s paint needs some love), most recently on a picture of a worse-for-wear F-35B (BF-02) after this year’s trials on the Wasp. The BF-02 photo appeared on this site about a month ago showing the new metallic looking horizontal stabs (“a” fix for the blistering issues no-doubt) with a very distinct tiger striping appearance to them, similar to what can be seen on the F-22 in the photo below. Internal structure showing through or a very intricate, varied conductivity mechanism for generating destructive interference for long wave radar signals when flying directly at them? The striping also closely matches the ones from the above Japanese diagrams of the F-22 sim showing the surface electrical currents.

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Sure, here’s a couple. First one is generalised comment, 3rd line in page 19A-5, the second link gives a table of geometric features and sensitivity to frequency/wavelength on page 133/134.

Since posting this, at what point did you realize that you got your fundamental maths entirely back to front for the second link. The equations on P 133 actually show that RCS decreases as wavelength gets larger for those shapes.

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As I said earlier in the thread, a good rule of thumb is the change in RCS is proportional to the wavelength^2.

[Which was completely and utterly mis-understood by MiG-31. Numbers below.]

Wavelength = c/frequency

So, if RCS = 1 m2 at 10GHz (wavelength = 0.03 m)

then at 8GHz (wavelength = 0.0375 m), RCS ~ 1.6 m2

At 1 GHz (wavelength = 0.3 m), RCS ~ 100 m2

The rule of thumb is applicable to LO aircraft. But obviously, its a rule of thumb, hence approximate and not to be considered exact. But its enough to show the undergraduate report as a load of utter balls.

So based on your rule of thumb which is exclusively dependant on frequency, the rcs of a stealth aircraft at 1ghz is still going to be thousands of times smaller than that of a legacy airframe, and subsequently will still have the same impact on detection range against low band radar as it does at xband.

Perhaps you could cite some sources to validate your “rule of thumb” and show rcs results for VLO airframes at different wavelengths as others have produced.

I really hope the lband topic is in relation to awacs support aircraft and not some misguided idea that a tiny linear lband array on a wing leading edge with a minuscule gain value is suddenly a silver bullet against stealth.

Whoosh.

Jessmo23 had no trouble grasping my point. It flew straight over your head though.

Your point was the modelling is too simplistic? Seems BAE disagreed when they bought into the sim.

The vendor must be wasting their time by marketing the professional version of the sim to military customers which features the same modelling but just an editable db.

There’s ways to edit capabilities without using the db, I’ve tested many different scenarios.

Conclusion that can be drawn is first shooters get a huge advantage. In many vs many, even when the final single missile pk is as low as 15%, first shooters will win.

Fine for you to be upset with the results (which are similar to the reports now coming out of the usaf and USMC) but there’s nothing to suggest an Su-35 with a slightly bigger radar is going to get first look on no f**ing around, VLO fighters that are pointing their stealthy front aspect at them.

Meh. Politicians make careers out of lying and twisting the truth.

I wouldn’t place much weight on their criticisms (or praise) of anyone.

Actually it was the RAAF brass that discredited him, not politicians.

-I am in lead of Su-35 group. I have typical armament of 2x R-27RE, 2xR-27TE, 2x R-77, 2xR-73 and Sorbstiya ECM pods.
-I am aware I am againist VLO targets, So I am flying at sea level, my radar is in high PRF at maximum volume scan, IRST on, and I am cruising at M0,9. One of my wingmen is jamming

That seems like an awfully unwise doctrine in a whole lot of ways:

– The one jammer has to constantly cover the whole sky across a massive frequency range (not happening against highly jam resistant APG-81s approaching from multiple directions, only takes one to track the Su-35’s for all F-35’s to be able to fire.)
– What’s the separation of the Su-35’s, if the formation is 80km wide then their l-band datalink emissions will be detectable from at least 80km. Not sharing data and coordinating – good luck.
– Whole plan relies on jamming technology being more advanced than enemy radar, that’s one big single point of failure. So odds are already down to 50% that it will be a bloodbath.
– No Su-35’s have any room to maneuver nor escape.
– IRST and missile warning range is severely limited due to higher air humidity and possibly clouds as well as IR noise from the ground itself
– Missile range is severely limited due to the boost phase being wasted in a hard upward turn and much denser atmosphere. So missile range is probably not much better than 15 km against a target up at 45-50k ft
– They are also in a position where missiles can literally be rained down on them from different directions.
– Range and endurance is severely limited resulting in more flights back to base/less airspace coverage over time/more time on the ground when fighting F-35’s that have better odds than…anything of hitting you on the runway

-15 degree below F-35 (also scanning the bottom not just front), while F-35 is trying to discriminate 3x Su-35s from ground clutter while actively being jammed by the one that fell behind.

Why would the F-35 not just direct its nose down at the target and fly at low speed?

All the while F-35s are maneuvering for trying to sneak vs Su-35s, why should Su-35 guys just wait? Againist VLO targets only a fool would fly straight in level, zig-zags in every few minutes will cover much greater volume of air, and would force F-35 to maneuver and match the Su-35’s course changes, exposing their higher RCS sides, and cut the enemy’s missile range by half.

If the F-35’s are close enough to require large course corrections to keep the target in a 120 radar arc and a 360 degree EOTS arc, then they are probably well within firing range already.

An F-35 with overly optimistic 0,001 sqm average RCS will still be detected from 54 km, well before it could launch its Meteor missile. However, RCS doesn’t work that way. There will be minimal points maybe as low as 0,0001 sqm, but there will also be spikes as high as 0,1+sqm, changing frequently with closure angle. Don’t start with “F-35 has 0.000X sqm RCS” crap, a human has 1m2 RCS. A bird has 0,01 sqm RCS; be reasonable. With constant operation of control surfaces, constantly changing approach angles, F-35 will not be completely invisible

The 0.001 figure is more likely a maximum for frontal sector RCS, and consistent with what has been said from certain officials it may also be as low as 0.0001, similar to the F-22. You seem to have difficultly grasping the concept that although an aircraft is a big object in the visual spectrum, it can also re-transmit very little energy in the 10GHz ish range when illuminated. Humans and birds are basically bags of water with highly electrically conductive (relatively) surfaces.

Stealth aircraft are shape optimized with sharp leading edges, swept back surfaces and covered in material perfectly matching the impedance of the surrounding atmosphere at the air/matching layer interface with conductive substrates to absorb EM energy. The materials on their leading edges are designed to gradually increase impedance, absorb the radar energy in the underlying structure and return some back as destructive interference. Some of this works in similar fashion to the pyramidal RAM structures of an anechoic chamber (walls of which are 1000m^s area in size yet have an RCS of -70dBsm and are smaller to a radar than a mosquito).

Find me 2 quotes from people who have “been there” at exercises and claim to have detected a properly stealthed F-22 on radar at range and I’ll quote 10 who say that they saw nothing on radar at all. A couple F-16 guys mentioned they found it boring because all they did was fly in clear skies, not seeing anything out there and kept receiving calls on the radio telling them they’d just been killed, over and over.

In fact, it will likely be just as hard as AIM-7 equipped F-16A defeating AIM-7 equipped F-4Es.

Or more likely a slaughter, as quoted by the sources who know and are there doing it, and the number of those saying the same thing is getting larger.

in a 24 vs 24 in a 300 km box, Su-35 will see and track every F-35 in the air, there is simply no room for moving around sensor coverages.

Sure there is, just operate out of allied countries, something F-35 operators have a plethora of. Just fly in from the perimeter and roll the enemy back. Besides the F-35 in defense would be an absolute nightmare to deal with, especially the B.

– The Simulator’s AIM-120D and Meteor have pretty much the same specs (except for radar signatures) in the sim. 75nm maximum range, and both have a PK of around 45% at terminal phase which gets adjusted by range, target maneuverability and target speed.

– Even though the database says IRST range is 100nm+, actual aircraft detection range is dependent on the aircraft IR signature, aspect and speed its travelling (they take into account leading edge heating at high mach). They are working on integrating IR signatures for afterburners still, but its not so important F-35 pilots would never use them on approach to a target.

– I feel they could increase the side aspect RCS of the F-35 but in every setup I’ve done vs the Su-35 its irrelevant, the F-35’s will always see the flankers coming from a long distance away and will always be able to avoid showing their side aspect before nailing the flankers from multiple directions, which in actual combat would seriously increase pk vs a maneuvering target than just a head on shot.

– They’ve for some reason configured the APG-81 to be a small classed radar (with pretty low range), perhaps to factor in LPI capability.

– PKs range from 45% at terminal phase down to 10% if you turn the maneuverability settings right up (by adjusting pilot ability) on the target aircraft.

Probabilities
– With an average PK of 20% per missile and with volleys of 4 missiles fired at each flanker, the chance of survival is 40% per aircraft. With an average missile PK of 30%, chance of survival is just 25%. With historical PK’s of 50%, chance of survival is 7%.

– With the same average PKs per missile but 6 missile volleys, chance of survival is 27%,12% and 1.5%

Here’s the F-35 vs Su-35 detection ranges for the default database aircraft in CMANO.

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