Sukhoi S-70 Okhotnik UAV

Trident said:
Things you couldn't make up...

That said:



<insert facepalm meme here>

Where to start... so based on the even older F100-PW220 engine alone, the X-47C was not a stealth drone either? Okay...

Or the fact that even the F-35 is still riveted aluminium to a non-trivial extent, while the F-117 was actually almost *all* riveted aluminium - both not stealth aircraft either, clearly.

Finally, the video provides a nice, clear view of torn CFRP skin with 45° fiber tow remains, proving point blank that the guy is oblivious to what CFRP actually looks like even when it's staring him in the face.

(Not directed at you Deino, I don't mean to shoot the messenger)
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Thanks … in fact I was hiking thru the forest when I saw it and I posted it for the images, not for the comments
 
This is the reason why twitter is such a plague, especially on knowledgeable sites such as this.
The forum is dumber as a result. (Not directed at you Deino, more certain users here who's sole contribution here is a string of often-slanted reposts straight from twitter)

The knowledge on this forum supercedes many of these self-appointed twitter 'experts' by a vast distance.
 
Trident said:
Things you couldn't make up...

That said:



<insert facepalm meme here>

Where to start... so based on the even older F100-PW220 engine alone, the X-47C was not a stealth drone either? Okay...

Or the fact that even the F-35 is still riveted aluminium to a non-trivial extent, while the F-117 was actually almost *all* riveted aluminium - both not stealth aircraft either, clearly.

Finally, the video provides a nice, clear view of torn CFRP skin with 45° fiber tow remains, proving point blank that the guy is oblivious to what CFRP actually looks like even when it's staring him in the face.

(Not directed at you Deino, I don't mean to shoot the messenger)
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Who are you to go against an "open source intelligence" twitter expert? ;)

I didn't comment earlier on this because of a feeling of hopelessness.
You are a better man than me.

Also, this puts the idea to bed that some here and on other sites have suggested that the Su-57 isn't being used (even rarely, peripherally, or in testing) on the outskirts of this conflict.
 
Gwalker18 said:
Was the missile strike a last resort in the event of a remote detonation failure?
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If it really had a self destruction ordinance onboard, my guess was they didn't use an independent communication system for it so when they lost comms they lost the ability to blow it.
 
Trident said:
Things you couldn't make up...

That said:



<insert facepalm meme here>

Where to start... so based on the even older F100-PW220 engine alone, the X-47C was not a stealth drone either? Okay...

Or the fact that even the F-35 is still riveted aluminium to a non-trivial extent,
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Really? Which parts are "riveted aluminum"?
 
QuadroFX said:
Controversial. Remote control must be organized by directional phased arrays of the S-111 system. It is nearly impossible to intercept control organized through directional antennas.
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I was thinking more like "lost comms" not "hacked".



Josh_TN said:
I suppose it cannot be ruled out, but I think it far, far more likely to be a fault in the control system. There is a rich history of losing control of UAVs only to have them bumbling into another country’s airspace, or a couple times the wrong continent IIRC.
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Yup. US sent a plane after a Reaper (IIRC) that had lost comms, but by the time the plane caught up to the Reaper it had regained comms. They still shot it down.



sferrin said:
Really? Which parts are "riveted aluminum"?
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Access panels, weapons bays, most of the internal structure...
 
Trident said:
Interesting theory, considering its radar (if any) is going to be considerably worse at the AWACS role than the Su-35's own.
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Probably simple data-sharing from the S-70 to the manned Sukhois which means they themselves don't have to radiate. Not as good as battle management from an AWACS, but a nice advantage for the Su-35. Particularly if it can get in closer to the lines.

Though conceivably the inverse square rule might mean more wattage down range than the AWACS is capable of from far beyond the line of battle at whatever distance they judge safe.
 
Ainen said:
It was shot already over Ukrainian airspace.
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Oh, oops! That's not good...


Ainen said:
Probably after desperate attempts to get rogue drone under control.
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Definitely. Can only imagine the level of panic when the drone is not where it's supposed to be and you lose comms.

Still seems a very questionable decision as to test-fly a drone that close to the fighting.
 
Scott Kenny said:
Definitely. Can only imagine the level of panic when the drone is not where it's supposed to be and you lose comms.
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Imagine the panic when a weary drone operator falls sleep at his console, then wakes up to find his VLO drone deep inside another hostile country and unresponsive to commands.

Not that that has ever happened of course….
 
IMO, it was not a loss of comms, but problems with FCS, which turned drone into MiG-23 Belgium crash cosplayer. Because usually if link with operator is lost drone returns back to base after some time.
I think it was somewhere as follows: problems with FCS, whcih made drone fly straight, airplane leader + ground team tries to solve issue to no avail, then decision to destroy the drone is made. Leader plane scrambles to intercept and by the time it caught up drone was well within ukrainian airspace. Pilot killed it so close to make sure that drone is killed properly, instead of relying just on radar data.
That's my take it.
 
Anduriel said:
IMO, it was not a loss of comms, but problems with FCS, which turned drone into MiG-23 Belgium crash cosplayer. Because usually if link with operator is lost drone returns back to base after some time.
I think it was somewhere as follows: problems with FCS, whcih made drone fly straight, airplane leader + ground team tries to solve issue to no avail, then decision to destroy the drone is made. Leader plane scrambles to intercept and by the time it caught up drone was well within ukrainian airspace. Pilot killed it so close to make sure that drone is killed properly, instead of relying just on radar data.
That's my take it.
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I share similar opinion on the cause, however I don’t think that your hypothesis on the final moments is true.

In my opinion: as the control was lost and Su-57 pilot scrambled to intercept drone, he tried to regain control using onboard S-111 array, indecisive to shoot it down without the order to do so. If the decision to shoot it down was taken as soon as the control was lost — the UCAV would be shot over Russian army controlled territory. So pilot just followed the aircraft, trying to return “UCAV back to its senses” until he received order to shoot it down. By that time they were 24 km deep into Ukrainian airspace.
 
NovaGA said:
I share similar opinion on the cause, however I don’t think that your hypothesis on the final moments is true.

In my opinion: as the control was lost and Su-57 pilot scrambled to intercept drone, he tried to regain control using onboard S-111 array, indecisive to shoot it down without the order to do so. If the decision to shoot it down was taken as soon as the control was lost — the UCAV would be shot over Russian army controlled territory. So pilot just followed the aircraft, trying to return “UCAV back to its senses” until he received order to shoot it down. By that time they were 24 km deep into Ukrainian airspace.
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From what I've heard it was shot down over Russian-occupied territory but momentum took it to the Ukrainian side before it hit the deck.
 
@Ainen : It was then most probably not on a recon mission but a strike one. The dual usage of their stealthiest known asset, high altitude and rugged glide bombs would suggest that launch should have occurred sometime earlier, probably much less than 5 minutes before (estimated cruise speed 900kph -250m/s - Glide range at alt <= 100km), otherwise they would have resorted to their usual attack profile (low alt toss).
The failure did then happen while the UAS and fighter where already flying in some sort of formation (probably loose). Both being seen in close formation suggests that the manned fighter aircraft might have closed-in for inspection before shooting it down.
The high energy egress move after is also remarkable.

It also probable that the S-70 had already started to manoeuvre out of its intended flight trajectory since it is curious to see a high flying stealth a/c cruising that close the FLOT at contrails height. Either it had already engaged in a slow descent or climb.

The shootdown is also atypical in the sense that the wreck came down almost complete but without the nose section despite the huge orange ball seen in the video. This would suggest that the missile didn't explode on impact but still shopped the nose tip section off going through. That is curious for what seems to have been an easy kill. See also how the airframe came down without being on fire, with the fuel tanks simply leaking by gapping holes. It would seem the missile went through without arming itself (too close a range?).
 

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Yeah, the video shows the aircraft basically losing most of forward momentum within 12 or so seconds after missile release. Which would not be strange as its not a streamlined bomb shape but a huge tumbling wing that produces lots of drag. Altitude is hard to assess but given that we have video of the shoot down taken from the ground, its likely medium altitude, not a high altitude flight. Even at high subsonic speed, i am not getting more than 3-4 or so kilometers of forward momentum.
 
TMA1 said:
I wonder if anyone here like stealth flanker who has some understanding of stealth materials and features and is relatively unbiased on either side could comment on what we might be able to glean from the images.
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This particular vehicle does not appear to be configured as a reduced observables vehicle. It may have been built as an aerodynamic or avionics testbed with no consideration for signature reduction.

In particular the leading edges of this vehicle have no RCS reduction treatments. This would be very obvious in the crash debris. An earlier vehicle, IIRC #2, appeared to have the expected edge treatments
 
TomcatViP said:
@Ainen : It was then most probably not on a recon mission but a strike one. The dual usage of their stealthiest known asset, high altitude and rugged glide bombs would suggest that launch should have occurred sometime earlier, probably much less than 5 minutes before (estimated cruise speed 900kph -250m/s - Glide range at alt <= 100km), otherwise they would have resorted to their usual attack profile (low alt toss).
The failure did then happen while the UAS and fighter where already flying in some sort of formation (probably loose). Both being seen in close formation suggests that the manned fighter aircraft might have closed-in for inspection before shooting it down.
The high energy egress move after is also remarkable.

It also probable that the S-70 had already started to manoeuvre out of its intended flight trajectory since it is curious to see a high flying stealth a/c cruising that close the FLOT at contrails height. Either it had already engaged in a slow descent or climb.

The shootdown is also atypical in the sense that the wreck came down almost complete but without the nose section despite the huge orange ball seen in the video. This would suggest that the missile didn't explode on impact but still shopped the nose tip section off going through. That is curious for what seems to have been an easy kill. See also how the airframe came down without being on fire, with the fuel tanks simply leaking by gapping holes. It would seem the missile went through without arming itself (too close a range?).
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There were multiple "weird" umpb strikes in the same area over last month, not corresponding with Ukrainian VKS tracking/warning channels.

Probable conclusion is it was s-70 doing sneaky trial bombing, and now got exposed through some bad code.
 
As you can clearly see in the footage, almost immediately after it got hit, the UCAV self-disassembled into two parts, one wing and center-fuselage+wing, which continued to descend almost vertically, as wind in the area was not strong.
 
Forest Green said:
If travelling at 600mph at 20,000ft it won't stop moving just because it gets hit. Also, it was nowhere near 24km:
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It stalled and desintegrated almost immediately after hit though; known overhead footage is Ukrainian.
 
S-70 was carrying these universal glide bombs , sort to Russian SDB except it packs 100kg of explosive vs 14kg in SDB , and its been used in Ukraine for a while now , same practice as in USSR where prototypes were sent to do combat testing . So far as far as we can tell this is first UCAV used in active combat



30393b32-be27-4d18-9fa1-9501b0624d43.jpg


Ukrainian_City_of_Kharkiv_Hit_by_New_Russian_UMPB_D-30_SN_Guided_Bombs_in_First_Use_925_001.jpg

quellish said:
This particular vehicle does not appear to be configured as a reduced observables vehicle. It may have been built as an aerodynamic or avionics testbed with no consideration for signature reduction.

In particular the leading edges of this vehicle have no RCS reduction treatments. This would be very obvious in the crash debris. An earlier vehicle, IIRC #2, appeared to have the expected edge treatments
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Even without special treatment, it should have very small RCS not just frontal but all aspect simply because of flying wing geometry clean enough contours no obvious radar traps , hidden engine compressor , flat nozzle, particularly against ground-based radars that only see the underside.

Lets not forget Super Hornet being touted as 'stealthier' than most , while literally resembling a flying radar reflector, corners and angles facing everywhere, you can only do so much edge treatment over shape itself .Stealth jerk-off competition is often purely looking at head on RCS where numbers are most favourable

Other aspects are not part of the advertising brochure as they are not quite as flattering
main-qimg-eb4f8c07093253691701e698e8029ad9.jpg
fro
 
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Ainen said:
It stalled and desintegrated almost immediately after hit though; known overhead footage is Ukrainian.
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It didn't:

View: https://www.youtube.com/watch?v=iVO8nIdntq0


...still going forward at altitude even after Su-57 has departed. Video is then cut to the part where it starts falling. It could quite easily have travelled the 5km or more. Plus I think the plan was to try stop it getting to Ukrainian territory, which would seem logical.

https://twitter.com/x/status/1842513328217760059
View: https://x.com/clashreport/status/1842513328217760059
 
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Mr.T said:
Even without special treatment, it should have very small RCS not just frontal but all aspect simply because of flying wing geometry clean enough contours no obvious radar traps , hidden engine compressor , flat nozzle, particularly against ground-based radars that only see the underside.
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Not really. The outer mold line of this aircraft is different materials with different electrical properties. The abrupt transition between aluminum and composite skins will produce a large radar return across a wide range of aspects. The composites themselves are a "radar trap", there is nothing that prevents radar from going right through them.

Untreated cavities are strong scattering sources. Of the cavities visible in the wreckage none appear to have been treated. A serpentine inlet duct does not do any good unless the inside is treated with an absorber.
 
quellish said:
Not really. The outer mold line of this aircraft is different materials with different electrical properties. The abrupt transition between aluminum and composite skins will produce a large radar return across a wide range of aspects. The composites themselves are a "radar trap", there is nothing that prevents radar from going right through them.

Untreated cavities are strong scattering sources. Of the cavities visible in the wreckage none appear to have been treated. A serpentine inlet duct does not do any good unless the inside is treated with an absorber.
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Many ways to skin the cat and we do not know enough from picture or two you have from the crash to make such definite claims
Monolitihc fiberglass might be 100% radar transparent , that does not to be the case with Carbon fiber composite ,and given that we have seen molds and plugs for both wing and center secton i wonder how much aluminum is there on outer skin ,composites are still screwed together at least till aircraft industry determined adhesive bond is enough.

Structural carbon fiber reinforced plastic, as used in aircraft fuselages and wings, is a radar reflector.

CFRP's RCS properties are similar to aluminum, except for unidirectional fiber, if its fibers are oriented parallel to the incoming signal's polarization.

ejL7S.png


https://www.researchgate.net/public...s_Section_of_Carbon_Fiber_Composite_Materials

7-12 GHz corresponds to the radar X-band, in which most military radars operate. A difference of a few dB for a narrow range of signals doesn't provide much concealment, so CFRP aircraft aren't inherently stealthy.

There are non-structural radar-absorbent materials that use carbon fiber chopped to specific length. They aren't strong enough to build high-performance airplanes out of, but can be applied on top of a structural CFRP layup, or embedded into a fiberglass layup.

One paper shows up to -18 dB peak reduction in RCS with 3.2% of short CF added to fiberglass, but that's in a narrow band. A different paper shows a more broadband -10 dB reduction for CF addition.

In general, CF must be combined with other materials, such as iron oxide, to provide comprehensive reduction.

A comprehensive review of carbon-based RAM shows that -10 dB reduction across the board is achievable with one material, but pushing it to -20 dB requires a mixture of different materials, in a layer about 2 mm thick. This has to be on top of the reflective structural skin.

Electromagnetic shielding uses the same conductive properties, but unidirectional fiber isn't a good fit for shielding, since it lets some signal through. Generally CFRP needs to be supplanted with metal mesh or a mat of chopped fiber to provide metal-like shielding.
 
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Mr.T said:
Structural carbon fiber reinforced plastic, as used in aircraft fuselages and wings, is a radar reflector.
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All materials reflect, absorb, and pass through RF energy to varying degrees. Conductive metals generally reflect more than they absorb or pass through. Fiberglass will generally pass through more than it will reflect or absorb, etc.

The electrical and RF properties of carbon fiber vary with fiber direction, length, "carbonization", angle, and other factors. Controlling these factors can result in a material where reflection dominates, or absorption dominates, or passing through dominates.

In the case of unidirectional "carbon fiber reinforced plastic" the RF properties vary greatly with angle and polarization. The material may be very reflective from one angle, and pass RF completely through at another! This is not a desirable characteristic.

From Jenn, D. C. (2005). "Radar and laser cross section engineering". American Institute of Aeronautics and Astronautics.

A composite material is composed primarily of a body constituent, or matrix, which gives it its bulk form. Additional structural constituents determine the in- ternal structure. These include flakes, fibers, particles, laminates, and fillers, as depicted in Fig. 7.19. The resultant properties of a combination of materials are determined in one of three ways. First, the net characteristics can be a simple sum- mation of the individual properties. An obvious example is a laminar composite, in which case electrical and thermal conductivity are given by a summation rule. A second way in which the properties of a composite can differ from those of the original materials is complementation. Each component contributes separate and distinct properties. Laminates and clad materials are examples. Finally, the third way is interaction. Each constituent supplements the others, and the final result is a material that has properties intermediate between those of the constituents or higher than those of both.
The four most common composites used in the aircraft industry are graphite/ epoxy, boron/epoxy, aramid/epoxy, and glass/epoxy. 17Extensive use of graphite/ epoxy is incorporated into the F/A-18 wing skins, horizontal and vertical tail fins, fuselage dorsal cover and avionics bay door, and speed brake. Graphite/epoxy is also in widespread use in commercial aircraft as well. The trend toward composites is not new; even older designs, such as the Lockheed L-1011, Boeing 727, and McDonnell-Douglas DC-10, made use of graphite/epoxy. Essentially, the entire structure of the Lear Fan 2100 is graphite/epoxy.
Scattering from a composite is determined as it is for any "pure" material; it is simply a matter of specifying/Zr, Er, tan 8,, and tan 8u. The complexity of the composite structure and constituents usually results in constitutive parameters that are at least mildly anisotropic and inhomogeneous. For example, fiber-reinforced materials have a dielectric constant that is slightly different for the electric field vector parallel to the fiber compared to the electric field vector perpendicular to the fiber. Likewise, the dielectric constant of each layer in a laminar composite can vary. Frequently, both these cases are treated by using an equivalent or effective permittivity and permeability. The electrical characteristics of several composite materials are summarized in Appendix E
The use of composites has both advantages and disadvantages insofar as the RCS is concerned. The (specular) reflection coefficients of these materials are usually less than those of metals. Traveling waves are also less of a problem because the surface impedance has a larger real part than a good conductor and the reactive part is not inductive. A disadvantage is that composites are penetrable; significant field strengths can exist in the interior of composite bodies. Interior metal structures that would normally be shielded by a conducting enclosure will scatter.
The penetration of waves through composites not only affects the RCS but also presents the potential for electromagnetic interference (EMI) between electronic systems. Care must be taken to shield and ground components properly, not only to reduce EMI but also for lightning protection. The latter usually requires embedding a mesh or wire grid inside the composite, which will also affect the RCS.
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Note that the paper your post (indirectly) quoted by copy-pasting from Stack Exchange, Riley 2015, measured from specific static angles : "These samples were then placed in an anechoic chamber and their RCS values were measured at normal incidence" .
 
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