Sukhoi Su-57 / T-50 / PAK FA - flight testing and development Part II [2012-current]

Except for stealth, which is a core requirement of being defined as a 5th gen fighter.
The mods here were smart enough to create a children's corner to discuss that kind of topic at the Su-57 stealth thread. You find all relevant opinions and data (or rather "data") there. No need to spoil this thread too, please.
If your victory is dependent on your airframe kinematics, you're doing it wrong, because that implies you're seeking out a "fair fight", when that's precisely the thing you should be avoiding. If you aren't cheating you aren't trying hard enough. And sensor fusion is a major step towards getting the information necessary to do that, and to get inside your opponents OODA loop. Hell, Ogarkov's Military Technological Revolution is a Russian idea, not an American one, though the US grabbed it with both hands as the Revolution in Military Affairs.

(The idea of stuffing an old airframe full of new avionics isn't as simple as you seem to think. And that's for any old airframe, a stealth airframe makes it massively more difficult).
When someone speaks about kinematics and good old physics, the Western reaction is to assume that means they are disregarding SA somehow. Since this is not what I have said, you may want to reconsider your reasoning.
 
Except for stealth, which is a core requirement of being defined as a 5th gen fighter.
The mods here were smart enough to create a children's corner to discuss that kind of topic at the Su-57 stealth thread. You find all relevant opinions and data (or rather "data") there. No need to spoil this thread too, please.
If your victory is dependent on your airframe kinematics, you're doing it wrong, because that implies you're seeking out a "fair fight", when that's precisely the thing you should be avoiding. If you aren't cheating you aren't trying hard enough. And sensor fusion is a major step towards getting the information necessary to do that, and to get inside your opponents OODA loop. Hell, Ogarkov's Military Technological Revolution is a Russian idea, not an American one, though the US grabbed it with both hands as the Revolution in Military Affairs.

(The idea of stuffing an old airframe full of new avionics isn't as simple as you seem to think. And that's for any old airframe, a stealth airframe makes it massively more difficult).
When someone speaks about kinematics and good old physics, the Western reaction is to assume that means they are disregarding SA somehow. Since this is not what I have said, you may want to reconsider your reasoning.

What if I'm looking for the new physical principles, since that what it seems like you're evaluating aircrafts based on.
 
In spite of the limitations of the F-22, I’m rather amused by those touting the superiority of the Su-57 as 5.5 generation or even better. The premise of arguing that the Su-57 is a half generation over the F-22 assumes many of the Su-57’s attributes from the “Megalopolis” upgrade program, which hasn’t even finished development. The izdeliye 30 engines being an example. Some of the claims put forth are also purely speculative. No source has ever stated that the izdeliye 30 engine is variable cycle. The airframe design of the Su-57 represent a different set of requirements, with range and payload being higher priority compared to the F-22.

Some of the points listed also seem like advertising talking points. Fixed inlet? “Advanced lift augmentation devices?” So what? I frankly don’t even see a tangible benefit of the former; the latter is pretty marginal.

In any case, the debate over a comprehensive MLU of the F-22 within USAF stems more from economy of scale rather than the physical limitation of the airframe itself. Perhaps the F-22’s airframe doesn’t have the potential to reach what USAF is looking for in the NGAD, but it’s quite presumptuous to somehow equate this as an example of the Su-57’s superiority; whose to say the Su-57 can meet NGAD requirements any better?

Before simply handwaving away the differences in stealth between the two aircraft, industry sources that I’ve spoken with have alluded to the Su-57’s LO design lacking features for the S-band, in contrast to the F-22. Certainly this would be a limitation for maritime strike.
That was a good post at least

I think the reasoning is pretty straightforward. The airframe of the Su-57 is intrinsically superior in range, payload, propulsion and has more resources for maneouverability. The engine part of it was what depends on Megapolis, but by now, 10 years on after the development of izd. 30 started and roughly one year away from state tests beginning, we know enough and the risk is low enough to start talking with some basis about it. The values I am giving are founded in statements by the designer, not in internet sources. I am the first sceptic, but after many instances of the same data I consider them solid enough not to be lightly dismissed.

Is izd. 30 a VCE? I said likely, because of a series of reasons. If you have a better explanation of how a fixed BPR engine can have at the same time higher specific thrust than F119 and the fuel consumption of the AL-31F, I am all ears, really. In the end, what is more difficult, to develop a VCE, or to create a fixed bypass engine with equivalent performance? BTW, the core of izd. 30 is currently being used for the development of the three stream engine that they consider 6G (izd. 30 is considered 5.5G by the manufacturer)

You don't see a tangible advantage of variable intakes at high speeds, or do you think such speeds are not relevant? Why does NGAD need speed among its main features, then? What is to be expected from a second stage Su-57, with higher specific thrust engines and 30% bigger intakes than F-22, in regards of supercruising? As to the payload and range features. F-22 is considered outdated and lacking on them, but Su-57, which has them plus quite superior propulsive arguments, is (widely, maybe not by you) considered 4.5G. That is BS of the highest order.

Do you think a lift augmentation feature like the LEVCONS is of no use, does it not help trimming the plane in supersonic and keeping the airflow attached at high AoA? This, as almost anything in the Su-57, was designed to match or surpass the F-22, designing to be worse from the beginning and coming late is simply a non workable strategy.

The issue with what is X gen is that US makes the claim, makes the narrative and declares who is entitled to carry the title. If you want that privilege to remain unchallenged granting those attributes at will is ok, but if the same features in NGAD define 6G but in Su-57 just 4.5, then I call it self serving and logically weak.

As to the S band features on the Su-57, it may be the case. I think this is a quite difficult topic on many regards and we addressed it in a specific thread for a good reason. I can say though, that modern lower band radars are declared to see US VLO without any problem. So they are also not stealth either, it seems.

trose213 said:
What if I'm looking for the new physical principles, since that what it seems like you're evaluating aircrafts based on.
I have no idea what you are referring to
 
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izd. 30 a VCE? I said likely, because of a series of reasons. If you have a better explanation of how a fixed BPR engine can have at the same time higher specific thrust than F119 and the fuel consumption of the AL-31F, I am all ears, really. In the end, what is more difficult, to develop a VCE, or to create a fixed bypass engine with equivalent performance? BTW, the core of izd. 30 is

currently being used for the development of the three stream engine that they consider 6G (izd. 30 is considered 5.5G by the manufacturer)
I think you can increase performance by increasing diameter of Fan and Compressor stages.
 
Again, we’re still talking about the planned Su-57M with proposed capabilities rather than what the current production Su-57 as ordered by the VKS is capable of.

Is izd. 30 a VCE? I said likely, because of a series of reasons. If you have a better explanation of how a fixed BPR engine can have at the same time higher specific thrust than F119 and the fuel consumption of the AL-31F, I am all ears, really. In the end, what is more difficult, to develop a VCE, or to create a fixed bypass engine with equivalent performance? BTW, the core of izd. 30 is currently being used for the development of the three stream engine that they consider 6G (izd. 30 is considered 5.5G by the manufacturer)
That variable bypass offers superior performance on paper is not being debated. I am questioning the assertion that the izdeliye 30 will be variable cycle; I haven’t seen this to be the case, and statements claiming this were usually made by journalists rather than from officials themselves.

You don't see a tangible advantage of variable intakes at high speeds, or do you think such speeds are not relevant? Why does NGAD need speed among its main features, then? What is to be expected from a second stage Su-57, with higher specific thrust engines and 30% bigger intakes than F-22, in regards of supercruising? As to the payload and range features. F-22 is considered outdated and lacking on them, but Su-57, which has them plus quite superior propulsive arguments, is (widely, maybe not by you) considered 4.5G. That is BS of the highest order.
I don’t see much benefit in the Su-57’s operating envelope. The airframe is designed with a maximum speed of about Mach 2, and like the F-22, mainly due to materials rather than drag limitations. A variable inlet’s benefit in this regime is marginal.

30% bigger capture area? Source? In any case, large capture area tends to have little to do with supercruise performance and pertains more to low speed engine performance in order to ensure adequate airflow; large capture area can lead to increased spillage drag, since an engine “consumes” as much air as it needs; this can be mitigated to some extent by the variable ramps.

EDIT: Don't know what you're measuring, but from official views, it's more like around 5% difference, not worth noting considering all the functions that the inlet provides and that the flow field is not necessarily captured by the frontal area. This argument of "oversized" inlets also ignores that the F-15's inlet capture area is smaller than the Su-27's, despite the F-15 using the higher mass flow F110-GE-129 in the EX.

Do you think a lift augmentation feature like the LEVCONS is of no use, does it not help trimming the plane in supersonic and keeping the airflow attached at high AoA? This, as almost anything in the Su-57, was designed to match or surpass the F-22, designing to be worse from the beginning and coming late is simply a non workable strategy.
The Su-57 is meant to meet the Russian Air Force’s requirements; I doubt Sukhoi or the Russian Air Force is looking to overmatch the F-22 stat for stat. Requirements are rarely defined in such a narrow manner, not to mention economic and political factors.
 

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Well some stats for the Su-57 like range and super cruise performance along with situational awareness capabilities that the 2nd version is better than the 1st version or the discontinued F-22. Dont think economic factors have stopped their progress in engines, avionics and designs.

I am assuming the reason most assume izdelie 30 was considered variable cycle is that high bypass ratio engines were common for their 4th gens because of territory size meaning range over speed. But it seems they are keeping that advantage along with bumping up the thrust to the advantages of a low bypass engine. Trying to find the source of the official that stated fuel efficiency of AL-31F.
 
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That variable bypass offers superior performance on paper is not being debated. I am questioning the assertion that the izdeliye 30 will be variable cycle; I haven’t seen this to be the case, and statements claiming this were usually made by journalists rather than from officials themselves.
I know no direct statement, but we know indeed it is not three streams. I said likely, so mine was no assertion. In the N+1 interview Marchukov was essentially saying the 5G engine is VCE, and izd. is considered 5.5G, so the hint is rather strong, more knowing the background of the research in YF120/izd. 20 by the end of last century. Then the provided engine performance is IMHO far from trivial with a fixed BPR. But as said, if any expert can enlighten us in that regard I would be a happy man, this is one the big remaining questions about PAK-FA.

I don’t see much benefit in the Su-57’s operating envelope. The airframe is designed with a maximum speed of about Mach 2, and like the F-22, mainly due to materials rather than drag limitations. A variable inlet’s benefit in this regime is marginal.
Well, I don't have access to the plane's requirements, but when the patent states an intake optimized for M = 2 to 3, I suspect maybe they do plan to go beyond 1.5 M. We know the F-22 max speed is also above 2 M. I would need to check, but I think that, in general, the fixed intakes are already starting to lose performance strongly from M 1.5 onwards.

30% bigger capture area? Source? In any case, large capture area tends to have little to do with supercruise performance and pertains more to low speed engine performance; large capture area can lead to increased spillage drag, since an engine “consumes” as much air as it needs; this can be mitigated to some extent by the variable ramps.
My own measurement with blueprints. To be honest, I am not sure anymore whether the exact value was 20 or 30%, but it was quite significant in any case. I would assume max thrust at very high altitude does require to maximize the airflow to the engine. I also assume there might be an element of growth reserve, specially if three streams engines are developed for the Su-57, which seems indeed in the plans from what we know about both the aircraft's and the izd. 30's development roadmap. These would greatly mitigate any possible spillage issues the oversized intakes may create with the first stage engine.

@tequilashooter:

Look at the N+1 interview with Marchukov
 
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Except for stealth, which is a core requirement of being defined as a 5th gen fighter.
The mods here were smart enough to create a children's corner
That's ad hominem. Debate the aircraft, not the person.

If your victory is dependent on your airframe kinematics, you're doing it wrong, because that implies you're seeking out a "fair fight", when that's precisely the thing you should be avoiding. If you aren't cheating you aren't trying hard enough. And sensor fusion is a major step towards getting the information necessary to do that, and to get inside your opponents OODA loop. Hell, Ogarkov's Military Technological Revolution is a Russian idea, not an American one, though the US grabbed it with both hands as the Revolution in Military Affairs.

(The idea of stuffing an old airframe full of new avionics isn't as simple as you seem to think. And that's for any old airframe, a stealth airframe makes it massively more difficult).
When someone speaks about kinematics and good old physics, the Western reaction is to assume that means they are disregarding SA somehow. Since this is not what I have said, you may want to reconsider your reasoning.
[/QUOTE]

If it comes down to kinematics, what did you do wrong that let it come down to kinematics? If you're citing kinematics as dominant, it suggests you've missed something. Kinematics are the backup to the backup to the backup. See the enemy, shoot the enemy before he knows you're there. If you don't get him with that shot, disengage, re-engage and repeat as necessary. If they try and force the merge, shoot them before they do. It's only once the merge is forced that relative kinematics becomes of measurable interest between combat aircraft. Basing your arguments of relative aircraft capability on kinematics says to me that you aren't focusing on what's actually significant.

Individual kinematics is of some relevance pre-merge WRT no-escape zones, but how two different designs compare kinematically is of interest only post-merge.

You realise that in all your assumptions that I'm attacking Russian aircraft, you've never asked me what I think of the F-22?
 
If it comes down to kinematics, what did you do wrong that let it come down to kinematics? If you're citing kinematics as dominant, it suggests you've missed something. Kinematics are the backup to the backup to the backup. See the enemy, shoot the enemy before he knows you're there. If you don't get him with that shot, disengage, re-engage and repeat as necessary. If they try and force the merge, shoot them before they do. It's only once the merge is forced that relative kinematics becomes of measurable interest between combat aircraft. Basing your arguments of relative aircraft capability on kinematics says to me that you aren't focusing on what's actually significant.
If we go with .0000001m2 or .00001m2 estimates than I am guessing the closer aircraft's get the closer they will be engaging a dogfight where a little kinematics matter I suppose. I remember the hype of the F-22 stating RWRs can detect targets passively at 460 kms which sort of means you get a jump start on decision planning as a pilot on where the target is and where the target is heading to create a surprise attack on how you would target that aircraft. The Su-57 on the other is like a giant flying antenna considering the arrays and they even proposed Rostecs 2014 GaN MMICs for all we know can be placed on the back tail of the aircraft for project megapolis and such. Lets say the RWR passive detection range for the Su-57 is 550kms. However since both aircrafts have their passive/active detection on the Su-57 is aware where the F-22 is heading 1st takes the 1st course of action to turn its radar off, approach F-22 from its side and usually RCS can jump up 100-1000 times in size than compared to approaching the F-22 from the front and the Su-57 pilots knows when to turn its radar back on approaching the aircrafts blind side? The F-22 can throw S maneuvers but any irregularities in passive detection the active radar will activate and notice huge RCS spikes because S maneuvers expose the sides of the aircraft.

If advantages of stealth can be kept with new ideas and patents to keep extra kinematic perks than I dont see the issue.
 
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If it comes down to kinematics, what did you do wrong that let it come down to kinematics? If you're citing kinematics as dominant, it suggests you've missed something. Kinematics are the backup to the backup to the backup. See the enemy, shoot the enemy before he knows you're there. If you don't get him with that shot, disengage, re-engage and repeat as necessary. If they try and force the merge, shoot them before they do. It's only once the merge is forced that relative kinematics becomes of measurable interest between combat aircraft. Basing your arguments of relative aircraft capability on kinematics says to me that you aren't focusing on what's actually significant.

Individual kinematics is of some relevance pre-merge WRT no-escape zones, but how two different designs compare kinematically is of interest only post-merge.
I am actually talking mainly about BVR. Think about the following:
- How is a 0.9 M, 40 kft F-35 going to battle a 1.7 M, 60 kft F-22, that can engage and disengage at will, and shoot while remaining out of range itself.
- How having a perfect SA gives you the victory, when you have missiles coming your way and you cannot shoot back

Such kinematic advantage gives the F-22 the higher ground, that is the kind of unfair advantage a lesser airframe cannot attain. Unsurprisingly, the air superiority asset of the USAF is the F-22 and not the F-35.

BTW, talking about shooting before the enemy knows you are there in the time of the radars that see a plane in the runway at 3000 km demands to make certain assumptions I am not sure I agree with.
 
So it looks like it isn't the production model in the new clips but the eleventh prototype, which features much of what all previous iterations had tested. One question I have tho is does the 511 have the DIRCM? If so are the turrets able to extend and recess in and out of the aircraft?
 
My own measurement with blueprints. To be honest, I am not sure anymore whether the exact value was 20 or 30%, but it was quite significant in any case. I would assume max thrust at very high altitude does require to maximize the airflow to the engine. I also assume there might be an element of growth reserve, specially if three streams engines are developed for the Su-57, which seems indeed in the plans from what we know about both the aircraft's and the izd. 30's development roadmap. These would greatly mitigate any possible spillage issues the oversized intakes may create with the first stage engine.
No, generally maximum Mach does not occur at service ceiling, as any cursory glance of various 1g envelopes would show. Furthermore, airflow to the engines is generally not a limiting factor in these conditions (where you actually have excess airflow that creates spillage drag), but rather drag, or in the case of aircraft like the F-22 and Su-57, materials. Sukhoi’s own patents and documentations even stated a reduction in maximum Mach to around Mach 2 in order to increase the amount of composite materials used.

I don’t dismiss the Su-57 as irrelevant, but I’m frankly seeing rather bold proclamations of the aircraft’s individual superiority (5.5 generation) based on components that are still under development, or even based on supposition or extrapolation, such as the supposed variable cycle nature of the izdeliye 30. I’ve not seen such claims from trustworthy sources such as Piotr Butowski (who makes very accurate predictions and even describes the number of fan and compressor stages of the izdeliye 30) or flateric.

I could be totally wrong but i don't think izd 30 is VCE. What is the evidence for or against it being VCE anyways. Looked back in this thread a bit and I never could get an idea either way.

edit: had to un-bold my text!
 
Look at the N+1 interview with Marchukov
Thank you, https://vk.com/@pakfa-plazmennyi-motor-n-1-pogovoril-s-razrabotchikom-izdeliya-30 now just a random question to any viewers

"In the engine of the second stage for the Su-57, the developers applied a number of new design approaches and technologies, so that the "Product 30" in terms of specific fuel consumption approximately corresponds to the al-circuit engine AL-31F (670 grams per kilogram-force per hour in cruising mode), but surpasses it in terms of specific thrust. The AL-31F and its variants are among the most fuel-efficient combat aircraft engines in the world; such engines are put on the Su-27, Su-30 and Su-34 fighters, as well as on the Chinese fifth-generation fighter J-20."


1626753754259.png

random google search gives me the Max weight on the Su-57 of 35,000kg and internal fuel of 10,300kg. Su-57 is a little heavier but has more internal fuel. Will the Su-57s max range be higher than the Su-27 along with the addition to supercruise? Trust me my curiosity for the F-22s ferry range on another thread was not of bad intention, I just love technology. :p
 
The F-22 has some nice rivets exposed with cracked RAM.
Thing is that there is no point to bother about the rivets, skin quality and RAM on both: be it an F-22 of USAF demo-team(which is depicted on that photo) or T-50 flight prototype #510.

BTW, not so long time ago someone already posted here the difference in skin and coating between the #510 prototype and #01 production airframe.
Exactly. Eighter people have very short memory, or they never actually read the stuff being posted here, only interesting in running a sh!tshow..

Anyway, the show must go on.
Do you think they get to sign more orders on Su-34 or Su-35S?

? They already ordered more at Army-2020. Batch of 24 more Su-34, followed by 76 Su-34M.
Another Su-35 contract was signed, I think suspected number was around 30 air-frames.
And of course 21 Su-30SM2.
 
The F-22 has some nice rivets exposed with cracked RAM.
Thing is that there is no point to bother about the rivets, skin quality and RAM on both: be it an F-22 of USAF demo-team(which is depicted on that photo) or T-50 flight prototype #510.

BTW, not so long time ago someone already posted here the difference in skin and coating between the #510 prototype and #01 production airframe.
Exactly. Eighter people have very short memory, or they never actually read the stuff being posted here, only interesting in running a sh!tshow..

Anyway, the show must go on.
Do you think they get to sign more orders on Su-34 or Su-35S?

? They already ordered more at Army-2020. Batch of 24 more Su-34, followed by 76 Su-34M.
Another Su-35 contract was signed, I think suspected number was around 30 air-frames.
And of course 21 Su-30SM2.
Apologies. I was not aware of the 2020 Army contracts.
So that amounts to what, 96 + 24 + 76 Su-34's ?
 

As part of the international aviation and space salon MAKS-2021, which began in Zhukovsky near Moscow, Mikheev, answering a question from journalists regarding the export prospects of the Russian fifth-generation fighter Su-57, said that Russia is currently consulting with five foreign potential buyers of this aircraft at once.

The head of Rosoboronexport did not name the countries interested in the new Russian fighter, but earlier in an interview he also reported interest in the Su-57 from "five potential customers from southeast Asia."
 
in the time of the radars that see a plane in the runway at 3000 km

Name a radar with that performance. OTH-B radars have the range, but not the resolution.
 
I still wonder if Sergey Bogdan has any family relations to the Bogdan at the Pentagon for being responsible for funding the F-35.
 
Unsurprisingly, the air superiority asset of the USAF is the F-22 and not the F-35.

Warfare doesn't occur in a blank void. It is a constantly varying array of opportunities spread across the landscape, and getting inside the other guy's OODA loop allows you to choose your fight and concentrate forces where you need them. 200 F-22s can only be in 200 places at once (and more practically 50), against a larger force of F-35s that becomes a problem, and especially if situational awareness allows them to concentrate numbers where you are, or where you aren't. If you have less than 100 Su-57 that problem becomes even more critical (particularly given the size of Russia and the length of it's periphery. Numbers matter, affordability matters.
 
Name a radar with that performance. OTH-B radars have the range, but not the resolution.
The resolution for what, for knowing that a plane is there?

The resolution for knowing where the aircraft is, not that there is an aircraft somewhere in the spread of their beam width at 3000km within a range accuracy of a few tens of kilometres.

And I've not heard any claim that OTH-B has the precise resolution to pick out an aircraft on the runway. Clearly they can pick out ships against the sea surface, but land tends to be a more cluttered environment.

I've also not seen any discussion of the vulnerability, or not, of OTH-B to ECM, which would be an interesting part of the discussion of their capabilities.
 
Warfare doesn't occur in a blank void. It is a constantly varying array of opportunities spread across the landscape, and getting inside the other guy's OODA loop allows you to choose your fight and concentrate forces where you need them. 200 F-22s can only be in 200 places at once (and more practically 50), against a larger force of F-35s that becomes a problem, and especially if situational awareness allows them to concentrate numbers where you are, or where you aren't. If you have less than 100 Su-57 that problem becomes even more critical (particularly given the size of Russia and the length of it's periphery. Numbers matter, affordability matters.
Thus they have a lot of air defenses and new ground radars to que the Su-57s for 6 air to air missiles for every 6 aircraft. Even 4th gens can be used.
 
If they're exposed they're not hidden.
aircraft need rivets or screws to hold their shit together, rather if they use paint to cover it or not take pictures of it I dont really care if one is phased out from service and other was prototype.
 
The F-22 has some nice rivets exposed with cracked RAM.
Thing is that there is no point to bother about the rivets, skin quality and RAM on both: be it an F-22 of USAF demo-team(which is depicted on that photo) or T-50 flight prototype #510.

BTW, not so long time ago someone already posted here the difference in skin and coating between the #510 prototype and #01 production airframe.
Exactly. Eighter people have very short memory, or they never actually read the stuff being posted here, only interesting in running a sh!tshow..

Anyway, the show must go on.
Do you think they get to sign more orders on Su-34 or Su-35S?

? They already ordered more at Army-2020. Batch of 24 more Su-34, followed by 76 Su-34M.
Another Su-35 contract was signed, I think suspected number was around 30 air-frames.
And of course 21 Su-30SM2.
Apologies. I was not aware of the 2020 Army contracts.
So that amounts to what, 96 + 24 + 76 Su-34's ?
More like 124 + 24 + 76. Also some pre-serials and early batch birds (not flying anymore).
 
Still not sure as to the nature of the big top plate over the HUD though.

Is it some sort of sun shade or just some integral frame to support the big display plates? The first HUD did not have it and it seems a questionable addition to me.
 
Perhaps its a ground shade to protect the HUD from Sun and heat while its on the ground?
 
I like the Su-57 cockpit, clean modern and notice the distinct lack of switches due to the big multifunction display.
 

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