What you call “dummy caps” looks more like blade antennas typically used for RF communication systems. They may have been embedded and moved elsewhere.

As visible the KS-O of the T-50-5 is basically located in between where the KS-U-1 and blade antenna are on the T-50-4. Just assuming that the comms antenna is fitted elsewhere, the KS-O would still obscure the LOS of the KS-U-1. Hence it will be interesting to see where both will be located on subsequent aircraft that are fitted with the full 101KS Atoll OEIS.

Perhaps the size of some of the components has changed necessitating the relative change in location. Can be quite common with prototypes, or they simply test the locations for suitability of different equipment.

Falcondude, an update to the post above. That patent ‘forerunner’ was filed on 06/08/2003*, that’s around the same time the RuMoD PAK-FA tender was awarded to OKB Sukhoi. This means this type of CNT RAM would have been a major design factor and consideration from the very start of the T-50 project.

NPO Saturn’s update and reworking of that development was focused mainly on overcoming increased IR signature issues of the material during radar absorption as well as refining composition and improving thickness.

Also, you need to bear in mind that @ certain wavelengths, particularly lower X-band (used for target discrimination and missile targeting), the more recently tested SWNTs are the best performers. Hence, that media presentation with Russian Academy of Sciences’ heads to determine the what, how & which composition of these RAMs/RAS’ to apply to the airframe, due to debut on the RCS & static model T-50-6 (1&2).

*http://www.freepatent.ru/patents/2300832

http://forum.keypublishing.com/attachment.php?attachmentid=221795&d=1381340187

Yes, similar information has been presented before, the crucial bit for me, is the date. So now we have a suitable timeline of events. Andraxxus provided a very good approach on his previous post which is answering my questions too.

………………

There is a name for what your posts are. Obscurantism I thought died in the middle ages, but apparently not.

Umm, isn’t Paralay’s picture showing that if anything, this engine progressed rather further away than a paper project? It probably wasn’t flight tested, but surely they must have built at least several test specimens. Btw, some sources (not sure how reliable) allege that this engine ended up in China, possibly being the base for their WS-15 said to produce 16,500kgf.

Back to T-50, indeed it is rather useless to “discuss” anything with some of these folks who feel the need to bring the “America strong!!!!!111!!!” and “F-35!!!111!” crap in this topic every once in a while (and this assuming that mister F.D. is not a troll). Much more interesting are the actual developments in this program, either the next flying specimen or the one after that reportedly will introduce “significant” changes- whatever that entitles (though no, they surely won’t have flat nozzles and one piece canopy and all that stuff). It will be very interesting to watch when they hopefully appear sometime in the mid /second half of 2014.

enough with the troll thing. And besides, this is also a debate thread, not just a news thread! No?

I believe I asked you before to find a single post that I claim “America strong!!!!!111!!!” !! I bet you won’t find any.

Unless you believe that when someone is saying that the “F-22 is the standard to match or beat” means “America strong!!!!!111!!!” !!! Do you?

There exists a patent from engine manufacturer NPO Saturn for a CNT RAM which is the work of 5 individuals, including the general manager of the Type 30 engine (Yuriy Martchukov). It was filed in 2011 and published this year. It attains an amazing -19dB absorption the 2-20GHz and is only 1.5mm thick. Remember, this is an additive to a polymer matrix binder and as such, is an integral structure, not a post-production RAM like on the F-22. Even if you assumed an unreasonable diminishing returns of 50% all of 3mm will deliver of 28.5dB! Sukhoi will take this value for the RCS ‘hotspots’ that run counter to the established orthodoxy of the F-22 (and others) like no flat bottom, round cowlings etc. 3mm for -30dB will solve those issues, it is nothing to do with ‘faith’- it is science, even the Indians are in the game!

Then you can argue ‘what about operating temperatures?’ Well that’s where VIAM come in with their 300°C polymer epoxy resins, incidentally, the same people who worked on RCS reduction of the Su-35S have a rival CNT RAM which they claim has an operating temperature of 200°C and is good to go, today.

Now pay special attention to this bit, concentrate hard!

That NPO Saturn patented CNT RAM is an update of a development by a separate bunch of people and, as such, is a direct forerunner to Saturn’s. The forerunner’s patent was published in June 2007, hence we can assume it was filed at least a year earlier. Given that there was a whole host of academic institutions hard at work on this technology in the mid-2000s, OKB Sukhoi would not only have had a good idea of the capabilities of this stuff, but risk would have been minimised because a whole host of people were separately working on it. Hence, it would have had a major impact on the T-50 design @ a relatively early stage of it’s inception. Much more so than on the F-35 which had already flown in the guise of the X-35 several years earlier.

Here is that forerunner’s patent dating from the mid-2000s:

http://www.findpatent.ru/patent/230/2300832.html. (I highly recommend you Google translate it)

…and here is official intimation for this type of RAM’s incorporation:

http://forum.keypublishing.com/showthread.php?126959-The-PAK-FA-News-Pics-amp-Debate-Thread-XXIV&p=2078208#post2078208

Did you sense anything in this post that was based on “faith“?

You are taking the word “faith” too literally. It is just an expression. I’ll read the links as soon as I get home, but thanks for focusing on something I put on the table.

In case you hadn’t noticed, in this thread in particular I have tried to move away from IEEE R&D studies levels, to focus on developments that have become (or will shortly become) commercially available- after all that’s what counts isn’t it?
.

OK, that is actually a different basis to the discussion. So, and you being the expert on the field please offer some help.

1. How many of the technologies you have mentioned so far in this forum have come to be commercially available when the T-50 design was being finalised. I.e. before the patterns were filed?

and I explain, for this to make sense in my humble opinion, for the the aircraft design to finalise with two nacelles -for example- that potentially affect frontal RCS, one would already be confident that composite technology can allow for the production of such an engine and such an inner wall to the ducts. Which for the engine at least it means that some kind of prototype should have existed prior to the final design of the T-50. Otherwise it would be pointless. Correct? The Su-35 would have been a prime candidate to develop such an engine version for, yet, if I am not mistaken, this is not so. The Su-35 has treated surfaces, not an engine based on these components, right?

Which means the technology was potentially not mature for the Su-35, yet it is for the T-50. Not impossible of course, but is an interesting point. Hence questions.

2. How many of these technologies have found their way into demonstrators? It could be that I just missed it, for which I take the blame, but it takes less time to point at the info, that call someone names, doesn’t it?

3. If some of the technologies are not yet ready for commercialisation, how come the design relies on them for something so vital as RCS reduction? There is no guarantee that they will be successful, is there? And the timescales seem to be short as announced by the developers.

Example, the F-35. Some of the avionics are still under development and not yet finalised, but even if the plane uses older avionics, its RCS reduction capabilities don’t need maturity in the future, they are already ready for application, which means you can still fly it VLO with an adapted F-16 avionics suite and it will still be VLO (or close). What appears to be the case for the T-50 is that if suddenly for some reason funding stops and the development is stopped, the T-50 will not be VLO, because some of the vital materials are not commercially available yet.
And all I am asking , is that the case?

Because if it is, then I am somewhat vindicated in asking, as the design by itself isn’t LO and requires extensive use of a second layer of technology on top of it to a greater degree than the US fighters did before it. So you get to different ratio of shaping / materials for VLO, for the T-50 in comparison to the F-22 for example.

Which brings me to another question. Was this an optimal choice? if yes, why? what are the reasons? confidence? matured technologies that -at least I missed-, previous prototypes?

I believe there will be more constructive dialogue if you stop thinking I am trying to insult you personally with these posts. You must also remember that what appears clear to you for some reason, isn’t clear to everyone.

Heinkel He 178 back in 1939 looked unlike any other aircraft. Judging by other available planes, it shouldn’t even have flown, simply because it didn’t have propeller. But it did, as the first jet engined fighter it was a revolution in aircraft technology.
In 1939; you two would say;
-an aircraft doesnt have propeller cannot fly, because all aircraft have propellers.
-He-178 is so revolutionary, it doesnt need propeller, because flies by not-yet-undisclosed technologies.

I would like to think my questions more along the line of, -because all aircraft have propellers and this one doesn’t, why doesn’t it ?

However I question;
-Why spend so much effort do create an inlet with both Ramps, together with paralelogram VLO geometry? 3d supersonic flow, 3d compressions, continiously varying geometry on 3 axis due to 3 inlet ramps… Its WAAAAY more difficult than designing and building a square nozzle, but they did.
-Why build so big composite panels? According to insider info, they are even having quality control problems to achieve that. Why go through the effort if they didn’t know/care?
-If they didn’t know/care, they could have gone for canards, if they only cared maneuverability, or could have put a flat surface for stealth. Instead they invented a new control surface called levcon to achive both. (I say invented because its not present on any fighter aircraft that I know of). Same goes for verticals; small for stealth but all moving for maneuverability; imagine the control difficulties not to mention materials. I mean, why go so much effort in order not to chose between stealth of maneuverability? I dare say, as far as aerodynamic+stealth combined solutions concerned, T-50 is FAR more innovative than F-22+X-32+F-35 combined.

Well you asking questions too, that’s good. As far as your last bit, I am not sure how to answer that. You see american VLO dogma would suggest you don’t use a structure like a levcon because the joint between the movable part and the frame would cause a seam that would generate backscatter from edge diffraction and creeping waves, which would be head on to the incoming radar for frontal RCS. Similar but not identical to the canard approach.

So again we have a propeller -non propeller type of situation, that we need to examine.