Btw u watch the AMK lecture yet?
Yeah very interesting, focus really is on the improved A2G. Which lines up with how much A2G stores impact EFT flight performance.
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Yeah, initialy planned for the a2a improvment it focused shifzed towards a2g.
The faster implementation newer armament trough the family system is intresting as well.
While it was horribly asked in the lecture.
Would be intresting if heavier a2a loadouts are considered.
I am personaly happy that my question about the functionality of the cannon got answered in combination with the AMK
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I tried asking if considering the graph they provided regarding loadout weights and fore/aft CoG shifts and didnt get an answer cuz of “security reasons”, which is super weird cuz THEY provided the graph, I was just asking if I was understanding it correctly -_-
In theory, 25% more lift should mean higher max takeoff weight, but the graph has me second guessing that…
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How would such a system even work on a missile like IRIS-T? If a 128 x 2 array has to be mechanically scanned from one side to another, how would you blank a section in the middle of that scan? I guess you could have a something like a camera shutter block the aperture during part of the scan, but such a system would probably be very complicated.
Also, if a small cluster of elements in a 128 x 2 array are damaged then you would end up with a dead stripe across the entire image. If a small cluster of elements in a 128 x 128 array is damaged, then theoretically you would just have a dead spot in the image and could use the rest of the array to still track the target. So in that respect a 128 x 128 array would seem to be more damage tolerant.
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That one i dont quite remember.
Just the ignored meteor question was a tad bit to blunt
Its not the array that is scanning mechanically, its a mirror, the linear array is stationary. If the intensity of the returns during the scan is approaching too high a level, you could just have the mirror skip the next few positions as needed before continuing the scan.
Or so is my understanding of how the seeker works and what could theoretically be done for DIRCM protection.
That is the reason why I initially brought up that the theory might be the risk of the elements being damaged, as fewer elements could theoretically mean proportionally increased damage from one or more elements being damaged, I just did a bad job wording it, sorry.
That being said, the time spent being irradiated by the DIRCM “directly” for the elements is much shorter than what a starring array would encounter, so the actual risk of the elements being damaged is also likely substantially lower.
Also, I do once again want to reiterate that I’m not pulling IRIS-T’s resistance to LDIRCM out of nowhere, the manufacturer themselves stated the IRIS-T has “excellent ECM resistance also covering modern blinding lasers” as late as 2018.
Do you think tower radar decoy would ever be implemented?
Maybe someday, but were likely pretty far from those still, since we dont even have basic radar ECM capabilities modelled, and even the expendable CM’s we have in-game are super rudementary.
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You can’t just skip positions if the mirror moves linearly across the FOV. If you want to go from one side of the FoV to the other the only way to do so by moving through whatever is between those two points. The mirror can’t just teleport to a new position. I guess you could speed up the scanning of the sections you want to avoid, but considering the thing is already scanning 80 times a second getting it to speed up and slow down without messing up the image processing for the rest of the frame is no small engineering task.
I’m sure the IRIS-T is resistant to LDIRCM, what I’m less sure of is if it is meaningfully better than any other IIR missile.
Where’s that from by the way? In this video the seeker image quality of IRIS-T looks pretty terrible compared to ASRAAM images you shared:
Simple: A Shutter. The shutter is closed while the optics move to the next line to scan. Instead of opening on a line it keeps being closed for the one line in question and opens only at the line after that.
With a Focal Array like the ASRAAM or AIM-9X (128x128 pixels) you can’t do that.
You can though, the same way you deal with the sun; the smaller the aperture in the optical train the less light from the scene get though to the detector array so you minimize what you can see, or use the optical train to deliberately defocus the image on the detector or you use the very low gain Sun-Staring detection diode.
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I was talking about the shutter in this case. I never denied that there are other techniques to cope with excessive radiation input :)
And is there any evidence at all that such a system is used on IRIS-T?
The cost and complexity of implementing such a system seems disproportionate to the benefit when evidence suggests that all IIR seekers are inherently highly resistant to LDIRCM. You’d need a shutter that can close and open again within in less than 1/5000 of a second, do so 80 times per second, and stay perfectly in sync with the sensor while the missile is pulling over 50g.
All of that work for a seemingly fairly marginal benefit. Particularly considering that at the time IRIS-T was being designed there was not a single operational LDIRCM system fielded anywhere in the world.
Isn’t it necessary to have a shutter for a line-scan device? Otherwise you would get streaks/motion blur on the image as the semiconductor cells never get properly discharged. Same effect as if you move a camera too fast causing motion blur. Every commercial line scan camera I found has a shutter (of varying type). Shutter times of 1/5000 aren’t that uncommon by the way as they can go up to 1/16.000 for consumer cameras (and that was 2012).
I’m not aware of scanned focal plane arrays requiring a mechanical shutter but it is really not my area of expertise.
From what I can tell from a quick search in the late 90s when IRIS-T was developed, cameras topped out at around 1/8,000. And those cameras didn’t have to function under more than 50 g’s of lateral acceleration.
So what I found: A line-scan camera has to use a shutter, otherwise the picture would be just “muddy” (they don’t work without a shutter). However modern cameras use electronic/global shutters without moving parts by activating and deactivating the CMOS cells.
If it’s an electronic shutter the g-forces are irrelevant.
But then the only advantage against LDIRCM would be the extremely short exposure time of the cells the moment they look directly into the LDIRCM transmitter (0,1 - 0,2 ms for one line scanned, 12,5 ms overall over one second or 1,25% of the time).
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From an IRIS-T brochure.
We dont know what the IRIS-T was actually tracking in this video, so its kind of wild of you to state the seeker image quality looks terrible when you dont even know what you’re looking at in the first place. Could be a small drone with a comparatively large IR source attached for example.
Or you know, you can go around the point you dont want to scan, rescanning an area you’ve already scanned? The seekers controller would know the position of the mirror at all times through the scan, since that info is required for constructing the final image from the scan, so it can just have the mirror pass through zones its already scanned and just omit said duplicate data from the final image processing. Its not like the mirror only has 1 DoF…
Its theoretically intensity gradient tracking at that point as a method of DIRCM HoJ, so it doesnt actually need an overly accurate image, it just needs to know where the approximate brightest spot that remains within the expected angle-gate. Dont need a whole lot of accuracy in tracking an intensity gradient…
Could also be a very distant target with maximum magnification and the pictures only shows a section of the image (the three pictures get gradually bigger the later they are in time).
That is a fair point.
The mirror itself does only have one degree of freedom, it spins around a fixed axis to sweep a 128 px tall row of pixels across a 128 px wide FOV to generate a 128 x 128 image. You seem to be suggesting the seeker scans the FOV like in the left image, it actually scans it like the right image (these are 5 x 5 images instead of 128 x 128 because I can’t be bothered to colour in that many squares).
Sure I guess the missile could hypothetically move the FOV around within the field of regard to try and force the mirror to miss part of the frame, but that would require some insanely rapid and precise seeker movement.
I doubt it is footage of a distant target because it seems to be synced near perfectly to the other two videos that show the missile hitting the target (whatever it is).
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