ActionJacksonDon’t forget that network integration is a key principle of the F-35’s systems architecture. So you could assume that a group of F-35s would autonomously share the load and scan different parts of the area of interest.
They’d continually share the data over undetectable links so updates are more frequent and resolution is higher than legacy systems. There’s not millions of lines of missions systems code in there for no reason.
A benefit of networked SAR processing is that F-35s can use high frequency, high gain radar modes which are inherently harder to detect by enemy systems (better directivity, weaker sidelobes)… So it’s a double benefit.
There seems to be a trend in development of US built high power amplifiers for radars that suggests US military often provides manufacturers with requirements for their products to support UHF up to 18GHz. For years the manufacturers have always had products in the catalog with these frequency requirements with ever increasing outputs. Seems possibly too coincidental that the F-35 program is probably the largest military buyer of radar HPAs in the world and this common frequency requirement just keeps popping up across all US military suppliers.
ActionJacksonIs there any information about how big the recovered tail sections of the downed Japanese F-35 were?
ActionJackson[USER=”29017″]ActionJackson[/USER] – That is too much separation and wouldn’t work. The technique assumes that the gain of the receiver antenna will be the same for both signals. That places a limit on how much spatial separation you can have on your two repeater antennas. Once the separation reaches the point where one of the targets will fall off the main lobe then it will appear as two separate targets, and the one that dominates due to gain will get locked on and hit.
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You can keep increasing J/S like that and it doesn’t hurt you, but after a point it doesn’t further help you either.
Yes, but using your sample chart showing the mainlobe with a half power beam width of 20 degrees, the hpbw of the radar mainlobe if the target is 20km from the radar is 7km wide, 3.5km wide at 10km and 1.75km at 5km range.
Against radars with higher directivity like 5 degrees, you could still use this jamming method with 1.75km separation of jammer emitters from 20km range.
ActionJacksonThanks, it is always a pleasure talking to a knowledgeable person.
As i figured, ALE-70, MALD can near completely blind the missile’s seeker if they are co-location with F-35. On the other hand, i didn’t forecast the average power and gain of missiles to be that good. Although 7% duty cycle is very low?[ATTACH=JSON]{“alt”:”Click image for larger version Name:tradar_a2a_by_stealthflanker-dbf5rk5.png Views:t0 Size:t65.6 KB ID:t3860123″,”data-align”:”none”,”data-attachmentid”:”3860123″,”data-size”:”full”}[/ATTACH]
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60 dB for J/S?? that is signal 1000.000 times weaker than the noise
Yes, the benefit of multiple, real stealth aircraft with very good, high powered jammers, flying in an angled formation with 1- 2km separation behind the lead aircraft (shooters).
ActionJackson[USER=”77826″]XB-70[/USER] Right on. Without access to excel where I am I have no ability to attempt the model.
Delta theta changes over time and increases as range reduces, meaning the the effects of cross eyed jamming amplify exponentially as the missile approaches the target. J/S also changes as range reduces as both the jammer and the missiles can increase gain.
As the error increases over time j/s also increases as the reference area of the missile’s radar in relation to the target decreases, but is also countered by delta theta decreasing as the aspect of the jammer changes. Other factors to consider are how the missile implements proportional navigation to lead the target (it doesnt head directly at the false track). At some point the missile may switch to hoj mode and intermittently switch on its radar to bait the jammer.
Lots of factors.
To do a simulated model based on the formula alone (without considering the factors above) it wouldnt be too hard to do 1000 iterations of the formula, updating missile and target positions and angles for each iteration then recalculating error.
The reason Im now interested in this is because of a combination of features present on the block 4 F-35.
– stealth (massive benefit to j/s)
– “You’re the one” missile threat detection
– autonomous cooperative ew
In stealthflankers spreadsheet, try entering a jammer emitter separation of 1000m or 2000m
and use 60db for J/S to see what I’m getting at.
ActionJacksonWell which part ? You can always download my spreadsheet and do it yourself.
https://www.mediafire.com/file/5t73k…cross+eye.xlsx
If i intend to do fraud etc.. i would not bother sharing source and images of the equations.
Now my question again, do you have comparable model ?
I’ll respond when I get back from holidays as this actually just made me aware of something huge relating to the F-35’s unique capabilities. Suffice to say that the block 4 F-35 is going to be the most terrifying aircraft in the BVR regime.
Fact though, your misinterpretation of that equation and how it relates to the actual modelling that was performed by the other source really poorly reflects on your understanding of simple maths and common sense.
In your “model” a missile is fired at a stationary target. At 20km from the target the missile (travelling at a unknown speed with unknown deceleration) is coaxed into an instant 0.16 degree turn and travels in a perfectly straight line to the point where it explodes, 57m from the stationary target. You sure you want to go with that? 🙂
ActionJacksonTheir model takes into account closing speed …etc and came up with the same result as yours. So obviously you’ve done the math wrong in order to achieve the same result with a single snapshot distance of 20km.
Fraud?
Feel free to share your worksheet though so we can see the magical “just because” coefficient added to the formula that’s been so prevalent in your other pieces of “work”.
ActionJacksonThe missile will hit. because your jammer can’t seduce the missile to track it and receive the technique. Otherwise if it can somewhat seduce the missile. It will still hit as your jammer cannot produce sufficient angular error.
The following is a calculation for the effect of a cross eye jammer,
First the geometry :
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The nomenclature
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Then the error equation.
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If J/S didnt reach that 20 dB (without gate stealing) or 3-6 with Gate stealing. The error generated (if any) will be very small. The error is measured from the center of the target.
The jammer has following specifications, based on DuPleiss’s Cross Eye jamming analysis :Amplitue differences between source and target : 0.9 (Ideal is close to 1)
Separation between jammer : Wingspan constrained thus for Su-35 sized aircraft it will be 14m
Radar look angle to target : 1 Degree basically at frontal aspect.The result with -5 J/S
[ATTACH=JSON]{“alt”:”Click image for larger version Name:tresult neg5js.png Views:t0 Size:t12.1 KB ID:t3859899″,”data-align”:”none”,”data-attachmentid”:”3859899″,”data-size”:”full”,”title”:”result neg5js.png”}[/ATTACH]About 1.1 meter to the left of fuselage of your aircraft. The missile will blow the left nacelle and maybe the internal weapon bay. Ideally you would want higher J/S to improve error to maybe 4 times of your wingspan so the missile will safely explode or pass your plane without subjecting it to too much debris from warhead explosion.
This is when you have 6 dB of J/S
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The missile will miss by 11.8 m from your centerpoint. better but if it can fuze it might still subject your aircraft to some debris
20 dB
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57 meters of miss distance. This might need very large warhead missile to take you down. typical A2A missile wont have sufficient warhead for this radius.
Simple J/S calculation is unfortunately would not tell you the whole story for deception jamming.
I wonder. I would say it will have longer detection range to those missiles as they move at some M 2-4. The burn through can’t say anything as no real parameters of those decoys nor the R-37 seekers ever released.
You haven’t modelled that properly. The miss distance is based on the target missile being at 20km only, 20 seconds away. Any fraction of a degree heading error at that point is very quickly recovered by the missile. You need to model it all the way into the point where human factors come into play…. Eg. The point where the pilot is not getting enough feedback that his jamming is working and has to evade and deploy his decoy.
I would think a pilot would need to see at least a km or 2 of miss distance at 20km range to be confident his jamming is effective.
To take a missile head on and maintain your heading as a missile approaches with .16 degrees angular error would takes balls of diamond.
ActionJacksonSee at 4’10 https://www.youtube.com/watch?v=IgD4QvxhFyU
Bravo, it almost got there, not quite though. Still haven’t seen an Su-35 sticking it above 100kts though in spite of the tantrums from the usuals.
Have you got a similar vid with a 4 or 6 missile load out?
ActionJacksonFortunately the F-35 in particular recovers energy extremely quickly. Not sure if you’ve ever seen it at an airshow, but after performing energy bleeding maneuvers it accelerates faster than most aircraft I’ve seen, including the f-22.
With the first shot advantage, fast initiali turn, energy recovery, 360* engagement with amraams where needed and the superior field of view with the aim-9x sensors it’s chances are significantly better than the mig-21 or any other fighter in the world for that matter.
ActionJacksonYep but whatever it takes to get into that 90 degree aim-9x hemisphere as quick as possible though.
The principle of the f-35 is that it’ll get the first shot on you in most scenarios, but even if you make the merge you’re still in trouble at the first turn. It only needs to keep the initiative until team mates arrive (f-35 is more likely to get reinforcements earlyein a fight) and snipe you from range with amraams.
I’m struggling to find videos of other aircraft that do these high aoa turns at f-22 and f-35 speeds. Rafale just doesn’t seem to do it (delta), and even the Su-35 seems to struggle at moderate speed. It usually only seems to do a decent instantaneous turn at almost 0 velocity.
ActionJacksonShape changing wings are coming, but possibly not in time for the 6th gen.
https://edition.cnn.com/style/articl…ing/index.html
It looks like stealth with a variable sweep wing may be possible.
ActionJacksonisn’t that a kicker. India spent all this money into the Pak-fa/FGFA/Su-57, and China (its main security threat) will operate them and develop tactics against them.
Also, if its true China is considering the Su-57. its a slap in the face to Chengdu and the J-20.
I don’t really see much alternative options for India though.. either they
1. Go at it alone (but if its anything like LCA.. it probably won’t reach service until 2050)
2. Buy F-35s (they probably won’t get the tech transfers they want, but could likely get them sooner than the other options here)
3. Buy TFX (probably unlikely, Turkey is pro-Pakistan)
4. Buy KFX (I think it will get built, but might not offer the performance they want)
5. Wait for Tempest or NGF (won’t appear any time soon, so there’s still that gap).
But the J-20 is by far a better (mission capable) design. They’d only be buying the engine and some avionics then throwing the rest away.
ActionJacksonI think the S-400 buy is a direct result of whatever threat Putin made to Erdogan following the Su-24 shoot down by the Turkish F-16 a few years back.
If you followed the various news agencies at the time, Russian media declared all out war on Turkey, showing “evidence” of isil trucks flowing into Turkey. It almost hated Turkey more than US and Israel.
Then Putin and Erdogan had a meeting, all was forgiven, and Turkey was suddenly buying S-400s.
I just wonder what the leverage was? It seems it was enough for Turkey to throw away it’s F-35 buy for a second rate air defence system.
ActionJacksonI think given you’ve been touting 90% rates for years and how the f-35 availability is so lacking by comparison, this thread is absolutely appropriate.
After all, we would want to clear up your misinformation (lies) in a thread that people who are interested in modern aircraft actually read.
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