Sukhoi Su-57 / T-50 / PAK FA first flight - pictures, videos and analysis [2010]

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Sundog said:
The T-50 has as much to do with the Su-27 as the F-22 does the F-15. They are both evolutionary designs of successful configurations. Sure, the designers study many other kinds of configurations, but it isn't surprising that given similar requirements to previous generations of fighters and the data base they're each working from they end up with designs with layouts similar to worked previously.

Besides, Sukhoi already made a fighter that was radically different, the Su-47, and they, like the U.S. with the X-29, found the design has many limitations when compared to more conventional fighters.

What does the fact of Sukhoi producing the Su-47 have to do with the fact that it seems obvious there is some Flanker in the T-50? (Literally, not just figuratively).
 
Sundog said:
The T-50 has as much to do with the Su-27 as the F-22 does the F-15. They are both evolutionary designs of successful configurations.

Garbage. The similarity between the F-15 and F-22 is purely coincidental in that they both have a large ‘box’ fuselage, a nose, two wings and tails. The similarity between the T-50 and Su-27 is not that they both ‘look’ alike. But rather that sections of the fuselage structure are identical. There is no such relationship between the F-15 and F-22. If there was McDonnell Douglas would own Lockheed by now thanks to their legal action.

Sundog said:
Besides, Sukhoi already made a fighter that was radically different, the Su-47, and they, like the U.S. with the X-29, found the design has many limitations when compared to more conventional fighters.

So what about the S-47. Was it in production? It was a one off prototype built by hand. There is no institutional link between the F-15 and F-22 but there is a big one between the Su-27 and the T-50.

If Sukhoi really wanted to build a LO aircraft they would have started with a clean sheet design and ended up with something with a box fuselage like their S-47 prototype. However clearly limited by funding and schedule they decided to reuse much of the Su-27 for the productivity advantages and ended up with an aircraft that can’t support the type of design needed to achieve -30, -40 dbsm level RCS.
 
Kovalchuk said:
That was probably the reason why Suhoi build Su-47 that had all pretty things like S-duct intakes, flat bottom. Then why to work with a "Su-27 structure and tooling" (what does that even mean? I guess SuperJet is a derivative of Su-27 since all Suhoi has is Su-27 tooling) when you could simply tweak Su-47?
I guess YF-23 was also a victim of "parsimonious financial environment" of Northrop/McDonnell Douglas:
or X-32
Your comparison is misleading. The picture of the yf-23 is looking from the bottom up, while the picture of the t-50 is looking straighgt foward, and in fact, slightly downward. As for the x-32. The x-32 is always an intrigue and special case study. There were many questions raised at that time about x-32's inlet in term of rcs. It can be assumed that either Boeing had to make the compromise or that their guys figured out something others don't. The latter is likely given that they and lockheed guys have been awarded the demonstration phrase, beating out other companies.
As for the Berkut, Berkut follows a different philosophy than t-50. It was internally funded as a technology demonstrator and stops there. T-50 is a project aiming at developing an operational fighter funded by the government, risk reduction is definitely a factor of entirely different level.
The comparison between the f-15 and f-22 is also irrelevant and has already been addressed in the thread.
 
sferrin said:
What does the fact of Sukhoi producing the Su-47 have to do with the fact that it seems obvious there is some Flanker in the T-50? (Literally, not just figuratively).
Trident said:
Abraham Gubler said:
It is an example of the many compromises built into this design because Sukhoi could not afford to develop an all new vehicle system and had to work with the Su-27 structure and tooling. All of this is to be expected however based on the simple parametric of return on investment.

Oh for crying out loud!

It's externally smaller than a Flanker, made from wholly different materials and Sukhoi was able to demonstrate and test an alternative fuselage design in the Su-47. Can we give that old chestnut a rest?

Abraham Gubler] [quote author=Sundog said:
Besides, Sukhoi already made a fighter that was radically different, the Su-47, and they, like the U.S. with the X-29, found the design has many limitations when compared to more conventional fighters.
So what about the S-47. Was it in production? It was a one off prototype built by hand. There is no institutional link between the F-15 and F-22 but there is a big one between the Su-27 and the T-50.

If Sukhoi really wanted to build a LO aircraft they would have started with a clean sheet design and ended up with something with a box fuselage like their S-47 prototype. However clearly limited by funding and schedule they decided to reuse much of the Su-27 for the productivity advantages and ended up with an aircraft that can’t support the type of design needed to achieve -30, -40 dbsm level RCS.
[/quote]

Hmm... You're assuming that there isn't a transfer of technology between companies in the United States or that the Sukhoi OKB of the late Soviet era still has the same staff, structure and tendencies in it's modern, post-coldwar layoffs, united aircraft industry guise?

I think this was Trident's point: Sukhoi has the ability to design a completely new aircraft that breaks past design doctrines and has a number of very high technological challenges (a narrow engined, canard equipped, large, supersonic, forward swept wing, fighter). In comparison, the T-50 appears to be a relatively conservative design, but the leading edge devices, all moving tails and improved FBW system means that it will probably be almost as manoeuvrable...

However, a conservative design can't be used to make such sweeping generalisations about a company's abilities. Some features may suggest lower RCS (or possible equivalent RCS achieved through more modern technology - but definitely with less of an emphasis on optimising RCS). But this is irrelevant to arguing that conserving the engine spacing and overall dimensions means that the design isn't really 'new' (which you'll forgive me for suggesting appears to have been your original angle).
 
Avimimus said:
Hmm... You're assuming that there isn't a transfer of technology between companies in the United States or that the Sukhoi OKB of the late Soviet era still has the same staff, structure and tendencies in it's modern, post-coldwar layoffs, united aircraft industry guise?

Not at all. Unless someone is transferring the production tooling for another fighter to Sukhoi then it makes no difference to wether they use the Su-27 as the basis of the T-50 or not. Plus bear in mind the US has a range of methods in place to avoid military technology transfer without approval.

Avimimus said:
I think this was Trident's point: Sukhoi has the ability to design a completely new aircraft that breaks past design doctrines and has a number of very high technological challenges (a narrow engined, canard equipped, large, supersonic, forward swept wing, fighter). In comparison, the T-50 appears to be a relatively conservative design, but the leading edge devices, all moving tails and improved FBW system means that it will probably be almost as manoeuvrable...

There is a big difference between what Sukhoi can ‘design’ and what they can build. The same goes for many aerospace companies in the world today.

Avimimus said:
However, a conservative design can't be used to make such sweeping generalisations about a company's abilities. Some features may suggest lower RCS (or possible equivalent RCS achieved through more modern technology - but definitely with less of an emphasis on optimising RCS). But this is irrelevant to arguing that conserving the engine spacing and overall dimensions means that the design isn't really 'new' (which you'll forgive me for suggesting appears to have been your original angle).

No sweeping generalisations just realistic interpretations also informed by the general pleading for investment Russian industry does around the world in a desperate attempt to update their industry plant from its Soviet era infrastructure.

What I have been trying to point out (I’ll leave arguing over straws to people with no idea) is that the T-50 is clearly an evolutionary design from the Su-27. Which means a range of things and doesn’t really matter if its ‘old’ or ‘new’ or whatever. What this means is when it comes to capability the T-50 won’t be easy to make LO. As has been clearly demonstrated by imagery the separated engine bays mean the forward face of the engine is exposed to radar. Also for its enclosed volume the T-50 will have much higher surface area than a boxier F-22 or F-35 and unlike a similar volume-surface area relationship in a flying wing much of this surface area will be exposed horizontally. The list goes on as do apparently the excuses.
 
hmmm... from what i've been reading, they'll be testing other configurations in the next prototypes assuming that the engine does fine. Not sure if it's true though
 
Abraham Gubler said:
What I have been trying to point out (I’ll leave arguing over straws to people with no idea) is that the T-50 is clearly an evolutionary design from the Su-27. Which means a range of things and doesn’t really matter if its ‘old’ or ‘new’ or whatever. What this means is when it comes to capability the T-50 won’t be easy to make LO. As has been clearly demonstrated by imagery the separated engine bays mean the forward face of the engine is exposed to radar. Also for its enclosed volume the T-50 will have much higher surface area than a boxier F-22 or F-35 and unlike a similar volume-surface area relationship in a flying wing much of this surface area will be exposed horizontally. The list goes on as do apparently the excuses.

Okay, your restated assessment once clarified, is essentially: The overall layout of the T-50 draws on past Russian experience and design philosophy. As such it's overall shape is not optimal for stealth at a given volume. This, along with the short engine bays, means that it will be a challenge to reduce the RCS to ATF levels.

Once the argument is removed of phrases that imply the design is essentially a rebuilt Su-27, and it is acknowledge that choice was exercised in most design features, the argument sound reasonable. I'd even agree with it.

I continue to have doubts as to the argument that the airframe layout will make it easier to mass produce (or the idea that tooling could be reused). The widely spaced engines allow for enhanced survivability and a larger/more flexible internal weapons bay. The relatively shorter design has advantages for manoeuvring. The short inlet may also be related to the engine development. If they'd wanted to move the engines to the centreline - it isn't that complicated a thing to do. Plus, there are factories which produced the Mig-25, Mig-31 and Su-24...

There are reasons to think that considerable design risks are being taken in other areas (from the tail planes to the fan-blockers). I doubt the overall layout is evidence that this is a very conservative design (especially the position of the engines - seriously?).
 
Wil said:
Nice and simple solution for radar blocking. I think that there are two blockers

there are no any blocker(s) on this specific T-50-1 PAV

Wil said:
And this other picture about the wingspan of PAK FA (image taken from Sukhoi video)

T-50 wingspan is not 14.70 meters. continue your research (hint: it's less)
 
Abraham Gubler said:
What I have been trying to point out (I’ll leave arguing over straws to people with no idea) is that the T-50 is clearly an evolutionary design from the Su-27.

And written like that, it's fine. What Sundog, Avimimus and I are taking issue with is that there is unlikely to be a single interchangeable structural assembly between the two, other than perhaps the nose landing gear and (currently) the engines. Like the F-15/-22, the mere fact that they look alike in terms of basic layout tells us little about the actual degree of hardware commonality. The fact however that the T-50 is probably physically smaller, made from fundamentally different materials and - even in its present prototype form - of far and away superior manufacturing quality suggest that no legacy tooling was involved.

Bearing this in mind, the Su-47 demonstrates that Sukhoi could absolutely have based the T-50 on a radically different fuselage design approach if required, so the reasons why they chose not to are obviously unrelated to a desire for commonality. BTW, while the Berkut certainly did benefit from funding from the Soviet era, post-USSR money went into MiG's 1.44 project, so much of the it was indeed completed on Sukhoi's own dime.

Long story short, while the Su-27 and T-50 are basically similar, the details are sufficiently different to indicate that the fundamental configuration was chosen on merit, not commonality. Just like the F-15 and F-22, in other words.

Abraham Gubler said:
Which means a range of things and doesn’t really matter if its ‘old’ or ‘new’ or whatever. What this means is when it comes to capability the T-50 won’t be easy to make LO. As has been clearly demonstrated by imagery the separated engine bays mean the forward face of the engine is exposed to radar.

Again, if you are arguing that Sukhoi is not aiming for the F-22 in terms of LO I'll readily concur, for all the reasons you state in this and another post. I disagree though that F-35 levels of signature reduction are impossible to achieve with this configuration, the F-32 design faced similar issues with its engine installation and was designed to match the same LO criteria as the F-35. At this point it is simply much too early to commit to such an assessment. In fact the careful effort made to shape the rest of the T-50's exterior for low RCS would make no sense if the current exposed and untreated engine installation was the final word.
 
Hello!

A miracle of PS, Saturn 117S engine installed on the PAK FA!



Flateric: Yes, it seems that the engine is not hidden. What a disappointment! The Sukhoi Su-47 Berkut and the Mikoyan 1.44 prototype engines were perfectly hidden ... What about the PAK FA?

Russia has time to change the design, I think. A 2010 version of Mig 1.44?

:-[ :-[ :-[ :-[ :-[
 

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Wil said:
Flateric: Yes, it seems that the engine is not hidden. What a disappointment! The Sukhoi Su-47 Berkut and the Mikoyan 1.44 prototype engines were perfectly hidden ... What about the PAK FA?

what about Hornet -> Super Hornet? What about F-15SE frontal RCS 'almost equal to F-35' according to Boeing?
we see just first prototype so far
 
flateric said:
Wil said:
Flateric: Yes, it seems that the engine is not hidden. What a disappointment! The Sukhoi Su-47 Berkut and the Mikoyan 1.44 prototype engines were perfectly hidden ... What about the PAK FA?

what about Hornet -> Super Hornet? What about F-15SE frontal RCS 'almost equal to F-35' according to Boeing?
we see just first prototype so far

Boeing is smoking crack that's "what about the F-15SE". ;)
 
flateric said:
what about Hornet -> Super Hornet?

Potential performance loss, although this might be a problem peculiar to the Super Hornet solution.

flateric said:
What about F-15SE frontal RCS 'almost equal to F-35' according to Boeing?

Hype :D

flateric said:
we see just first prototype so far

Exactly. A good example of what can be done in terms of RCS is, as has been mentioned a few times already, the F-32. Lingering questions about performance remain, but wouldn't Boeing's ATF entry have required a blocker as well?
 
Avimimus said:
Once the argument is removed of phrases that imply the design is essentially a rebuilt Su-27, and it is acknowledge that choice was exercised in most design features, the argument sound reasonable. I'd even agree with it.

No, no and no. Trying to manipulate what I’m saying so it fits your agenda is not a very good idea.

Trident said:
And written like that, it's fine. What Sundog, Avimimus and I are taking issue with is that there is unlikely to be a single interchangeable structural assembly between the two, other than perhaps the nose landing gear and (currently) the engines.

See above. No point in adding anything new or restating the analysis for a 3rd or 4th time. If these guys don’t want to see what is right in front of their eyes then who cares.

sferrin said:
Boeing is smoking crack that's "what about the F-15SE". ;)

Not quite. While you and the other guys I’ve quoted above have no means to validate Boeings marketing statements their customers do. So going out and saying X when it’s actually Y in something as directly measurable as RCS is something that will get them in the proverbial big time.

However “frontal RCS” is a very wide definition. Typically in ‘stealth’ aircraft this means the entire frontal arc up to 30-40 degrees either side of boresight which in the case of an LO aircraft provides a very significant tactical advantage. However frontal RCS can also mean a very tight arc of 2-4 degrees either side of the boresight. In this case the LO only provides a tactical advantage in head to head engagements in limiting the engagement range of the enemy. But it won’t hide you from volume search and the like.

So in the case of and F-15SE it won’t be hidden from any volume search radars (TPS, AEW&C) or even fighter search radars. But once it points itself at the bad guy and they close to engage the bad guy won’t be able to track it and engage with its missiles until they get into visual range (merge, etc).
 
Wil said:
Russia has time to change the design, I think. A 2010 version of Mig 1.44?

Yes, let's hope the Sukhoi engineers will read this forum and realize their mistake in time :)

Come on, people. The PAK FA is not the first stealth design to not use an S-curved duct. It's nothing to be disappointed about.

[quote author=flateric]
there are no any blocker(s) on this specific T-50-1 PAV
[/quote]

Are we sure? During the JSF flyoff, people kept insisting they could see the X-32's engine compressor, when in fact they were seeing the inlet baffle, which looked very much like engine blades. Either way, the engine face WILL NOT be exposed on the production version, we can be sure of that.
 
Please watch this before you discuss RCS.
I did. Its a very neat idea in reducing the majority of the engine face RCS and especially that feature of the F-22 radar that can recognize the enemy plane exact type by counting the blades on the fan.

Still, when you are aiming to reduce fundamentally an RCS and keep performance high, the last thing an engineer does is introduce more complexity and weight into the equation. While, I agree that this is probably among the most ingenious ways to reduce the RCS of an existing aircraft with a strait duck, you will be sacrificing performance and introducing and extra few point of failure.

A newly designed VLO aircraft will never resort to such mechanical solutions. 5th generation fighters like the YF-23 and F-35 proved that you can go supersonic without a variable geometry intake and do not also feature a divert-less inlet for no reason.

B)
 
So, let's discuss why it's such a short and straight duct in the T-50?

In the 20 years it's passed since the ATF designs were shown, it could seem obvious that you should have the intakes quite far in the front and then some snaking of the tubes. A relatively straightforwad way to add forward stealthiness a lot.

Does the engine suffer from the less clean air in an S duct? Are the US engines far more advanced in this regard? Is that the real reason? How many billions have been spent in IHPTET and VAATE and other programs? Or more surface drag in a long tube?

Or is it the more complex tooling? Or the significant complication that 3D curving inlets produces - everything in the mid and aft fuselage interacts with them and can not be designed separately.

The engines are widely separated in the T-50 - is there some advantage to wide inlet separation? Survivability? Missile smoke ingestion? Runway debris? Stores placement? Airflow cleanliness at sideslip? I don't know much at all about this, so I'd be interested in hearing from someone who perhaps does...
 
Certainly the engine placement increases survivability and allows for larger internal bays. I'd be curious to hear about other reasons. Cruise efficiency? Behaviour at high AoA? Easier modification to accommodate the new engine? I'm not really qualified to guess.

Abraham Gubler said:
Avimimus said:
Once the argument is removed of phrases that imply the design is essentially a rebuilt Su-27, and it is acknowledge that choice was exercised in most design features, the argument sound reasonable. I'd even agree with it.

No, no and no. Trying to manipulate what I’m saying so it fits your agenda is not a very good idea.

My olive branch.

Quite frankly, I know longer really have an idea of what you are talking about. So, I'll simply let the subject rest.
 
Now I do remember the French saying that properly seperated inlets like on Rafale are safer for the loss of an engine at take off or landing.
Something about a the risks of air building up and splling over into the working engine causing troubles.

But thats a piece of poorly remembered stuff so take it with a pinch of salt or twenty.
 
lantinian said:
Please watch this before you discuss RCS.
I did. Its a very neat idea in reducing the majority of the engine face RCS and especially that feature of the F-22 radar that can recognize the enemy plane exact type by counting the blades on the fan.

Still, when you are aiming to reduce fundamentally an RCS and keep performance high, the last thing an engineer does is introduce more complexity and weight into the equation. While, I agree that this is probably among the most ingenious ways to reduce the RCS of an existing aircraft with a strait duck, you will be sacrificing performance and introducing and extra few point of failure.

A newly designed VLO aircraft will never resort to such mechanical solutions. 5th generation fighters like the YF-23 and F-35 proved that you can go supersonic without a variable geometry intake and do not also feature a divert-less inlet for no reason.

B)

OH, Need me to remind you that compare to DSI, that CARET inlet is not a pure none-door inlet?
I didn't say VG inlet would be on PAKFA, that actually is a V-C inlet.
 
Avimimus said:
Quite frankly, I know longer really have an idea of what you are talking about.

That's been clear from the get go. But please don't allow me to distrub your T-50 fantasia, I just wish you wouldn't do it here at this forum.
 
http://www.redstar.ru/2010/03/24_03/2_03.html
 
mz said:
Does the engine suffer from the less clean air in an S duct? Are the US engines far more advanced in this regard? Is that the real reason? How many billions have been spent in IHPTET and VAATE and other programs? Or more surface drag in a long tube?

It may not be US engines that are more advanced, but US modeling and simulation tools. In the US it's become part of the design and development process, that may not be the case elsewhere.
 
Avimimus said:
http://www.redstar.ru/2010/03/24_03/2_03.html

Do I understand the article correctly to say that Sukhoi initially developed five alternative designs for the PAK FA? If only we could see the other four . . .

mz said:
Does the engine suffer from the less clean air in an S duct? Are the US engines far more advanced in this regard? Is that the real reason?

One disadvantage of an S-duct is the internal volume consumed by the duct, taking up space inside the aircraft that could otherwise be allocated for fuel or a weapons bay, etc. This issue was briefly addressed in the well-known Code One magazine article about the evolution of the F-22 design.

As someone has already pointed out, Sukhoi used an S-duct on the Berkut, so the lack of one on the PAK FA can't be blamed on any kind of technical difficulty. For whatever reason, it was a deliberate design preference.
 
Gavin said:
As someone has already pointed out, Sukhoi used an S-duct on the Berkut, so the lack of one on the PAK FA can't be blamed on any kind of technical difficulty. For whatever reason, it was a deliberate design preference.

You'd be hard pressed to find anyone in the LO business who would think a beehive box (if that is what Sukhoi plan to stick between the engine and the intake) is a better way to shield the front of the engine from radar than an S-duct. But the limitations of the available volume from reusing the Su-27's seperated engine bay design mean its radar blockers or naught.
 
mz said:
The engines are widely separated in the T-50 - is there some advantage to wide inlet separation? Survivability? Missile smoke ingestion? Runway debris? Stores placement? Airflow cleanliness at sideslip? I don't know much at all about this, so I'd be interested in hearing from someone who perhaps does...

In choosing the podded engines configuration (303B) for the F-14 Grumman said the reasons over a more conventional fuselage configuration (303C) were:

* supersonic combat ceiling performance (ie more lift less drag)
* isolated inlets and nozzles (precluding the F-111B’s TF30 interference causing maximum performance problems)
* no need for boundary layer diverter (large displacement between inlet and fuselage)
* engine growth potential (easier to fit bigger engine bays with nothing surrounding them but air)

Since the Su-27 and subsequently the T-50 basically copy the F-14’s configuration down to the main gear bays in the wing gloves (with the obvious exception of being fixed wing) the same reasons should apply.

The downside of the configuration is it generates a lot more horizontally facing surface area for reflecting radar. Particularly in the insides of the engine pods which is outer mould line that just doesn’t exist on a box fuselage aircraft. Also much of the interior volume is of very little height (in the area between the pods). This reduces useable volume for things with high height demands like S-ducts and internal weapon bays.
 
Another downside to the widely spaced engines is the significant decrease in roll performance, because you are distributing the weight away from the center of rotation.
 
Although with the 3D TV being spaced apart and imparting more direct force, wouldn't that reduced roll effect be negated? I may just be imagining things but I thought that was one of the reasons MiG's and Su's have their nozzles further from eachother compared to western fighters.
 
Although with the 3D TV being spaced apart and imparting more direct force, wouldn't that reduced roll effect be negated? I may just be imagining things but I thought that was one of the reasons MiG's and Su's have their nozzles further from eachother compared to western fighters
Your argument has some scientific but not historic basic.
MiG-29 and SU-27 were designed well before trust vector control as we know it today. The reason there was survivability from a catastrophic failure of one engine affecting the other. The russians has always like to build planes that are are likely to be shot at before they can shoot back. Whether that's operational pesimism or simple pragmatism, otherс more qualified here can tell.

Regarding the roll rate influence.
If spacing the engines ever further оут did increase aircraft roll rate, we would be seeing a lot more configurations of fighters with engines on the wingtips ;) The truth is that, aerodynamic surfaces provide just as much control authority without the accompanying weight. You just need to keep the wingspan short. The easiest to maneuver design is the one that has it mass as close to its center of gravity as possible.

The main reason for spacing of the engine on the T-50 is not to enable better use of trust vectoring in roll (that is a side effect) but to create a space where the main weapons bays will be located. Their configuration is the main design driver of the T-50.
 
SOC said:
Kovalchuk said:
I guess YF-23 was also a victim of "parsimonious financial environment" of Northrop/McDonnell Douglas:

Bad example, given that this was not the production intake design.

Perhaps this should be moved to the YF-23 thread but it appears to me, based on the EMD drawing available, that you can still see the engine face from certain aspects. There may be some caveats here though. One is that return off the engine face may not reflect directly to the source and would be broken up and absorbed by the duct. The other is that the reflection itself may be aligned with the lobe off the wing and other aligned surfaces. Either way the F-23 apparently was way in the blue in the ATF KPPs and beat the F-22 "on the pole" so its academic in any case. The F-23's inlet doesn't apply to the T-50s either.

BDF
 
Several analysists noted that the high wing sweep are for supercruise. I think like the x-32, the high wing sweep is so that the wing can be thicker to accomodate the L-band radars and copious amount of fuel without having to pay a drag penalty. I don't think the higher wing sweep angle indicate a better supercruise or top speed than seen on the f-22.
 
Hi!

Some interesting images from Paralay site...



The farther away blades look strange. No? ??? ???



A proposed radar blocker?



To be continued...

;)
 

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I like that solution. No moving parts, short, light and cheap looking ::)
 
I want to see what it does to pressure recovery and airflow characteristics compared to a baseline configuration, preferably in the form of multiple graphs across different AoA and Mach numbers up to the intake's design maximum. I'd also like to see weight and cost figures plotted against an equivalent serpentine duct.

My suspicions are that it'll play merry hell with the PR and airflow while costing less mass, size, and money than a serp duct, but that its aerodynamic performance could be greatly improved on with careful design.
 
Hello...

We remember. Some old pictures (2007 year) of RCS studies on a early model of PAK FA. I do not remember the name of the Russian institute that conducted the studies. :(









Good weekend...!
 
BDF said:
The other is that the reflection itself may be aligned with the lobe off the wing and other aligned surfaces.

That would be my guess as well. There's no point in trying hard to hide a reflection which will coincide with the airframe's leading edge spikes anyway. As you say, of questionable relevance to the T-50 though.

donnage99 said:
Several analysists noted that the high wing sweep are for supercruise. I think like the x-32, the high wing sweep is so that the wing can be thicker to accomodate the L-band radars and copious amount of fuel without having to pay a drag penalty. I don't think the higher wing sweep angle indicate a better supercruise or top speed than seen on the f-22.

Interesting thought, except the T-50 wing is in fact very thin :) Not sure if it will cruise faster than the F-22, but thickness was apparently not the consideration behind choosing the sweep angle.
 
see the model flight "demo" in youtube makes me want to see the real thing do the same and even more :D

(that ofc in behalf of the people who've seen it ;) )
 
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