Sukhoi LTS (CheckMate)

[paralay]

The Korean is a direct competitor of the LTS, but without weapon bays and a promising engine.
It will be interesting to compare them

 

[Blitzo]

+1
Checkmates main competitor will be FC-31, assuming the Chinese allow it to be exported.

I don’t think the Koreans will find any buyers who aren’t either in the F-35 camp or Checkmate/FC-31 camp already in terms of politics.

Considering that the Chinese scored an own goal in that they never allowed the J-20 to be exported even in an internationalised variant, then I think that I could expect the same thing to happen to the FC-31 as well, so I hope that Sukhoi should take advantage of this situation as well and to export as many Su-75s as possible.

The difference is that J-20 was never considered to be allowed for export, and I wouldn't be surprised if a deliberate reluctance to sell their "most capable aircraft" exists not dissimilar to the US attitude towards selling F-22. Putting it another way, I don't think the export success of J-20 was ever a barometer for the way CAC or the PLA would've approached the aircraft as a program, and I doubt they would've entertained the idea of selling it to begin with.

FC-31 -- or perhaps more likely an export variant of the domestic Chinese J-XY or land based J-XY -- on the other hand, not only has been openly offered in concept for foreign interest, but is also much more appropriate for export compared to J-20, being a smaller aircraft with lower payload, aperture sizes, in all meanings of the term.


Whether an eventual export-variant J-XY/FC-31 is eventually offered (I think the earliest this would be is in the late 2020s, after development of the respective aircraft had completed and after production of J-XY for the navy and land based J-XY for the air force have been underway for a few years), I can only see a few markets where both it and Su-75 would have a chance in... meaning I can't see that many places where either one of them would compete or cannibalize the other's potential sales.

 

[LMFS]

I don't really think F-35 is in anyway a competitor of Checkmate in the export market.

I know what you mean, but technically they are the closest. They are the only single engine 5th gen multirole fighters, with pretty similar sizes, payloads, ranges and features. But for political issues, they are natural competitors.

A country which could buy the F-35, ie. which that would be granted EL without problem wouldn't consider Checkmate in its very nature or vice versa.

These programs are calculated not just with the current political context in mind, but with a perspective of at least 15-20 years. What today seems impossible tomorrow may be completely normal. Said for CAATSA, economical constraints, political alignments, balance of force regional and global... our current understanding is quite short lived.

A necessary political reference is the increasing assertiveness of both Russia and China and their intention to create a parallel international financial structure. If they succeed, many of the current market considerations would simply not apply. Not pretending to discuss the likelihood of this development, but to provide context for the environment that designer and customer countries may consider.

KF-21 is a in quite of a limbo right there.

The issue with this and other 5th gen projects is mainly the lack of their own engine technology, which totally compromises the available motorization options and hence the planes' layout. They are twin engine, based on F404 derivatives and therefore less optimized economically and also physically bigger. Besides, the exposure to technology restrictions from third countries is something customers may not want to put up with, see the recent flop of Turkish T129 sales to Pakistan for exactly that reason.

Unsurprisingly Russia and US are the only ones betting on single engine designs, mainly because they are the only ones with a valid propulsive solution for this type of plane. In the case of Russia the bet is even more ambitious, since the engine is essentially the same present in the Su-57 and therefore the fleet integration much more complete.

The potentially real and actual competition against Checkmate imo is the FC-31,

As China gets more proficient and gains soft and hard power, their military sales will indeed increase substantially. The advantage of the LTS as said above is its clever layout, very reduced price and single engine architecture. It should be competitive even in price with Chinese alternatives, but the influence of the Chinese economic weight may more than compensate for that.

 

[helmutkohl]

The Korean is a direct competitor of the LTS, but without weapon bays and a promising engine.
It will be interesting to compare them

later versions will have a bay. You can clearly see the space for them below in this fuselage section
however the bay "doors" are covered by a panel for semi-recessed missiles.

I don't understand why they didn't go straight to a bay and adopted a phased integration approach
also not sure if there is an issue with the engine. the F414 provides sufficient thrust.

i also dont see them competing much either, except maybe in SE Asian markets
Indonesia is already getting them as they are a partner country. Philippines, Malaysia and possibly Thailand may have interest.
Turkey nope, they have their own project. Iraq, maybe since they already use the golden eagle.
the LTS main rival will likely be the FC-31

 

[Anduriel]

also not sure if there is an issue with the engine. the F414 provides sufficient thrust.

The issue is not with engine itself, or TW ratio (2xF414 combo is slightly more powerful than single F135, and if there will be an EPE engine, KF-21 would eclipse F35 in agility, hell, maybe it will do so from the get go, since Korea doesn't need to compromise design for VSTOL and carrier ops).
The issue is that KF-21 is not totally indigenous and has a lot of US parts or parts with US intellectual property. That's puts KF-21 export prospects into the question, as I doubt that US will be willing to allow KF-21 to compete with ther own F-35, plus there is always an otion to forbid export in a country that US doesn't like, or even if plane is sold before, simply cease to sell spares for engines and ground entire KF-21 fleet of a country US doesn't like).
This way FC-31 and LTS have it much easier as they are fully indigenous and no 3rd party can block export or support (assuming CAATSA is non factor).

 

[kaiserd]

There may well be countries that the US may not be especially enthusiastic to supply the F-35 to but for which they wouldn’t choose to block other aircraft with some US-content.

And CAATSA and other sanctions and other related diplomatic and economic aspects are very much a significant factor and won’t just conveniently be wished away. Indeed these issues are looking likely to significantly worsen in respect of programs/ products like the Su-75.

So while the KF-21 will have its own issues to overcome to start winning export orders it is not facing nearly the same level of inherent challenges the Su-75 is facing in this regard.

 

[helmutkohl]

also not sure if there is an issue with the engine. the F414 provides sufficient thrust.

The issue is not with engine itself, or TW ratio (2xF414 combo is slightly more powerful than single F135, and if there will be an EPE engine, KF-21 would eclipse F35 in agility, hell, maybe it will do so from the get go, since Korea doesn't need to compromise design for VSTOL and carrier ops).
The issue is that KF-21 is not totally indigenous and has a lot of US parts or parts with US intellectual property. That's puts KF-21 export prospects into the question, as I doubt that US will be willing to allow KF-21 to compete with ther own F-35, plus there is always an otion to forbid export in a country that US doesn't like, or even if plane is sold before, simply cease to sell spares for engines and ground entire KF-21 fleet of a country US doesn't like).
This way FC-31 and LTS have it much easier as they are fully indigenous and no 3rd party can block export or support (assuming CAATSA is non factor).

yes thats exactly why I said that the market for the KF-21 is not the same with the LTS in most cases.
Even if they changed the engine, Lockheed has significant influence over the project, and at the end of the day the KF-21 will likely only be sold to the countries that the US is okay with.

That said I also agree with Kaiser, there may be countries that the US is okay with, but not necessarily trust with the F-35, or may raise objections from another ally. I.E. Malaysia, perhaps a Middle Eastern country that buys western but may not be able to get the F-35, i.e. Qatar, Oman, etc.

the LTS will be fighting the FC-31 instead, and in this case, the FC-31 has a leg up since its actually flying.

 

[Maro.Kyo]

Unsurprisingly Russia and US are the only ones betting on single engine designs, mainly because they are the only ones with a valid propulsive solution for this type of plane. In the case of Russia the bet is even more ambitious, since the engine is essentially the same present in the Su-57 and therefore the fleet integration much more complete.

Well that is only partially true since during the early days of C102/202 and C501 models, KAI and ADD considered a single engine layout as well, much more similar to the size of the F-16, as that was closer to what the program was aimed for at the time(better than the F-16 block 52+). Considered propulsion option was a F110-132.

Anyways, enough going off topic and back to the LTS, I do tend to agree that what would be one of LTS' greatest strength in terms of commercial competitiveness is its single engine layout. As you've put, only the US and Russia currently possess and are ready (in various aspects) of designing and manufacturing engines of such capability, that a single engine could power a stealth fighter with a sizeable IWB for the moment.

edited for clarity)

 

[kaiserd]

With respect China is closing in on such capabilities and the UK/ France/ Europe have had this capability for decades.
Indeed Russian military/ fighter engines are arguably less advance than their Rolls Royce and Snecma contemporaries and there is is little basis to to think this will change.
In terms of civil/ non-fighter engines Russian engines are significantly inferior (and this technological superiority of UK & European civil engine technology does feed into and impact the military side).

 

[haavarla]

With respect China is closing in on such capabilities and the UK/ France/ Europe have had this capability for decades.
Indeed Russian military/ fighter engines are arguably less advance than their Rolls Royce and Snecma contemporaries and there is is little basis to to think this will change.
In terms of civil/ non-fighter engines Russian engines are significantly inferior (and this technological superiority of UK & European civil engine technology does feed into and impact the military side).

Well with the civilian PD-14 Engines and the coming of final Su-57 engines, the Russian Aviation Industry will take a leap of fait.
Right up under western engines sphere.
Beside, the recent engines on Russian Helios are also good.

 

[kaiserbill]

With respect China is closing in on such capabilities and the UK/ France/ Europe have had this capability for decades.
Indeed Russian military/ fighter engines are arguably less advance than their Rolls Royce and Snecma contemporaries and there is is little basis to to think this will change.
In terms of civil/ non-fighter engines Russian engines are significantly inferior (and this technological superiority of UK & European civil engine technology does feed into and impact the military side).

There is a lot that is simply wrong in this post, in all politeness.

 

[Archibald]

With respect China is closing in on such capabilities and the UK/ France/ Europe have had this capability for decades.
Indeed Russian military/ fighter engines are arguably less advance than their Rolls Royce and Snecma contemporaries and there is is little basis to to think this will change.
In terms of civil/ non-fighter engines Russian engines are significantly inferior (and this technological superiority of UK & European civil engine technology does feed into and impact the military side).

There is a lot that is simply wrong in this post, in all politeness.

I would nuance that a little. Military wise the Russians have truly impressive capabilities to churn big and powerful engines. France is presently stuck with M88 and RR with EJ200: the russians at least have much more choice.
Also compared to the Soviets day durability and reliability probably have vastly improved: worlwide Su-27 variants (in China and elsewhere) seems better than (back in the day) Mig-25 or those horrible Indian MiG-21 crashing by the hundreds...

On the civilian front... well it is much more murky, for a simple reason: Soviet airliners, and Russians afterwards, were swept by Boeing and Airbus. What's more, upgraded variants got CFM56s or GE or Pratt engines, from the 1990's... and even then they went nowhere (il-96 and others).

And then there is the Sukhoi engine case: they did it with SNECMA (if not mistaken, SAM 46, can't remember the exact name).

 

[overscan (PaulMM)]

EJ200 is more advanced technologically than 117 which is a modernised AL-31F. Look at the blade counts for fan and compressor, pressure ratio, temperatures, use of blisks and single crystal blades.

Its not in the same thrust class as 117 because it is smaller. It is thrust rated reasonably conservatively in favour of long service life.

Izdeliye 30 should be technically comparable to EJ200 but 20 years later.

 

[haavarla]

In the way they design the fan blades, the tiny cooling channels inside, the material choice, the forge prossess and the shape.
If Idz 30 is running at a higher temperature, and you do not melt the blades.
Then by definition; the Idz 30 is more advance over the EJ200.

what they did on the 117S, its rather an engenius but also simple solution. They increased the diameter of the fan.
Why? because they could. The Flanker design is much older vs EF. Still its way more forgiven when it comes to upgrade.
Makes for lots of trust increase for the bucks too.. which never hurts. Sustainability is king.

 

[LMFS]

[/QUOTE]

Its not in the same thrust class as 117 because it is smaller.

That is the whole point in the discussion, that Europe has (currently) no engines in the size needed for a single engine plane with the capabilities of the LTS or the F-35.

It is thrust rated reasonably conservatively in favour of long service life.

What is the service life? M88 was not famous for having a long one.

Izdeliye 30 should be technically comparable to EJ200 but 20 years later.

I hope you are not saying that in earnest. Even a cursory check of known parameters puts them almost one generation apart.

EJ200 is more advanced technologically than 117 which is a modernised AL-31F. Look at the blade counts for fan and compressor, pressure ratio, temperatures, use of blisks and single crystal blades.

Yes, because it was developed at least half generation after. While Europe was busy with the EJ200, Russia was developing the AL-41F which was a true 5th gen engine that received a huge amount of resources. Reported TIT was already more than 100K above the value we have for the EJ200

As to the available engines, and even when the izd. 117S and 117 are just derivations of the AL-31F and that shows in the stage count, do you think they have such inferior materials and technologies? Have you really checked TIT (Russians already state openly to be working at 2000K) or TWR? And the AL-41F1 does not have single crystal blades?

 

[LMFS]

Nope. Russia has that tech for quite some time already but didn't implemented it into serial engines.

Do you have further details? As you say Russia is known to have that technology and they jumped from 1500 hours operational life in their engines to 4000 hours with 1000 h between overhauls with the latest batch of engines like the 117S and the RD-33MK. The izd. 117 is a 15 tf engine for which 5th gen technology level has been explicitly stated.

 

[totoro]

UK and European engine developments, I'm sorry but this is just hilarious, what Euro engine is currently flying that is comparable in class to first stage Izd.117 engines flying right now on Su-57, much less the Izd. 30?

M88s and EJ-200s are just magical apparently. Hyperdrive enabled even!

I can't find reliable source for 117 engine, but there are good sources for 117S engine used on Su-35, to be compared with EJ200 data.

Turbofan aircraft engine AL-41F-1S | Catalog Rosoboronexport

The AL-41F-1S (article 117S) aircraft engine is a modular two-shaft turbofan engine with thrust vector control and integrated digital control.The engine is installed on Su-35-type aircraft.As ...

roe.ru

https://flotprom.ru/industry/images/Saturn_eng.pdf

https://www.eurojet.de/wp-content/uploads/EJ_Brochure_2019.pdf

117S
First flight of the engine on Su-35 in 2008
Weight dry 1604 kg
Inlet temperature 1745 K
Full afterburner thrust: 137 kN (14 000 kgf)
Max military thrust: 86 kN (88 000 kgf)
Special power condition thrust: 142 kN (145 000 kgf)
Lifespan 4000 hrs

EJ200
First flight of the engine on Eurofighter in 1995
Weight dry 990 kg
Inlet temperature 1800 K
Full afterburner thrust: 90 kN (91 177 kgf)
Max military thrust: 60 kN (61 180 kgf)
Lifespan 6000 hrs

Using those, one sees the inlet temperature is higher for EJ200, as is the thrust to weight ratio.
117s full afterburner thrust to weight ratio 1: 8.73
117s max military thrust to weight ratio 1: 5.48

EJ200 full afterburner thrust to weight ratio 1: 9.21
EJ200 max military thrust to weight ratio 1: 6.18

Now, one could say 117s also has TVC, which EJ200 doesn't. That in itself is a capability that is not here compared, but the TVC surely makes the 117s somewhat heavier than it would otherwise be, without it. Just how much would 117s weigh without it is, sadly, unknown precisely but this pretty good source says the difference is 30 kg https://www.uecrus.com/eng/products/military_aviation/al31f/

So using 117s weight of 1574 kg, we get the following thrust to weight ratios:
117s full afterburner thrust to weight ratio 1: 8.89
117s max military thrust to weight ratio 1: 5.59

So, as any engine can be uprated but at the cost of maintenance and life hours - it seems pretty safe to say that of the two engines, EJ200 and 117S, the EJ200 is more advanced. Yes, the 117S has also that emergency rating which is a bit higher, but that's really a matter of how much compromise one wants with the life expectancy of the engine. We don't know for sure, but it's plausible that the 117 engine (without the S) on the Su-57 has achieved its slightly higher ratings by compromising the life expectancy even more.

As said, any engine can do it. EJ200 also had variants in developments which lowered the life of the engine, in exchange for more thrust. Version with 72/103 kN more thrust was on offer at some time, but instead what those advances in engine tech were ultimately used for was prolonging the maintenance time between overhauls from 1600 to 2000 hrs. (Which likely lead to the advertised 6000 hrs lifespan)

Especially considering the year of each engine's utilization, most people will likely conclude that EJ200 is indeed more technologically advanced than the 117 family. For sure more advanced than the 117S.

Now, when we get good sources on Izd.30 engine - that'll warrant another comparison. It may very well be that Izd.30 shows it's a more advanced engine than EJ200. But let's wait for some sources for such a claim.

 

[helmutkohl]

just deleted a bunch of off topic non-sense here.
This is the LTS/Su-75 thread, not the Snecma, MiG-21, F-4, or whatever thread.

 

[Scar]

This is what i was talking about. No doubts Western engines are somewhat better in terms of resource life, ratios etc. But this thread is dedicated to the fighter jet concept called LTS. Again, every construction or machine is a summ of technologies available to designer, designer's decisions and the concept. So having the better engine or other component technologies doesn't mean the final design will be better in combat.

 

[LMFS]

I can't find reliable source for 117 engine, but there are good sources for 117S engine used on Su-35, to be compared with EJ200 data.

The Flotprom document is a good find, thank you. Does it say anything about izd. 117S' TIT? I also had that same value you mention, but I did not find any reference to it in the pdf.

As to how valid this is as a definition of state of the art of currently available Russian engines:

Izd. 117S is an export engine with known data. For izd. 117 we only have some intentional leaks here and there. As per Pogosyan, it should be 150 kg lighter with 2.5 tf thrust more than AL-31F for a TWR of 10,95. It gets 1 tf more than the 117S being developed almost at the same time, with 117S having already an enlarged LP compressor with increased airflow, so if this extra thrust does not come at least in a big part from increased temperature, I don't know how did they make it, given the basic architecture did not change. May have a shorter life, I don't recall clearly having seen that value for that engine.

Now, when we get good sources on Izd.30 engine - that'll warrant another comparison. It may very well be that Izd.30 shows it's a more advanced engine than EJ200. But let's wait for some sources for such a claim.

We have quite a few claims already by the designer: TWR is higher than 10, specific thrust is highest around with SFC of AL-31F, generation acc. to specific parameters is 5+/5++

 

[VTOLicious]

Fyi, the Checkmate does not have a bifurcated inlet (Which I had also originally thought). It's a single inlet duct like the F-16. The center support in the inlet functions like that of the F-16s for structural support. There are some good images looking in the inlet further up this thread and you can see that. I'm saying that in reference to the 3D model shown a page back.

Every picture I saw has the red cover blocking any further than a meter or less. Can you provide a link or post one of those images you are referring to? Thanks!

Edit: anyway I'll post a render of the inlet I did before July 20th. After MAKS21 show, when I saw that "splitter" down there I thought it was way too wide for being just a structural support, maybe the starting point of a bigger bifurcation around main fuel tank or the rear cockpit of the two seater. And if you can lead me to that images I'll be more than happy to correct my model!

Bifurcated or single duct, is the mystery solved yet?

 

[paralay]

solid pipe

 

[stealthflanker]

It's single duct. like in here :

Altair Agencja Lotnicza

www.altair.com.pl

You can see the "splitter" actually terminates.

 

[Willythekid]

Nope. Russia has that tech for quite some time already but didn't implemented it into serial engines.

Do you have further details? As you say Russia is known to have that technology and they jumped from 1500 hours operational life in their engines to 4000 hours with 1000 h between overhauls with the latest batch of engines like the 117S and the RD-33MK. The izd. 117 is a 15 tf engine for which 5th gen technology level has been explicitly stated.

According to this source, the AL-41F-1S (Saturn 117S) engine would have an operational life of 4,000 hours, and a TBO of 1,500 hours.
The manufacture of single crystal blades in Russia is already a long-standing applied technology. As has the technology of ceramic materials, at least since 2019, as reported at the time by UEC-Saturn.

IN-DEPTH: A look at Russia's enhanced Sukhoi Su-30SM2

The Su-30SM is now well established in Russian service while also enjoying mild export demand. An enhanced derivative, dubbed Su-30SM2 and currently in development, is primarily aimed at meeting the Russian Naval Aviation requirements, as we report

www.key.aero

Frames from COMBAT APPROVED, Su-57 video (Part II, I think)

 

[LMFS]

Is the patent for the LTS already published, and did anyone manage to find it?

https://tass.ru/armiya-i-opk/14165627

https://tass.ru/armiya-i-opk/14165873

https://tass.ru/armiya-i-opk/14166043

https://tass.ru/ekonomika/14166303

 

[raptor82]

Is the patent for the LTS already published, and did anyone manage to find it?

https://tass.ru/armiya-i-opk/14165627

https://tass.ru/armiya-i-opk/14165873

https://tass.ru/armiya-i-opk/14166043

https://tass.ru/ekonomika/14166303

Here：https://new.fips.ru/registers-doc-v...37B-597E-4B5C-AA56-FCE718499776&TypeFile=html

 

[overscan (PaulMM)]

(54) LIGHT TACTICAL AIRCRAFT

(57) Abstract:
The invention relates to the field of aviation, in particular to light tactical aircraft with low radar visibility. Light tactical aircraft contains a fuselage with side tail booms, wing panels, tail, air intake, power plant and jet nozzle. The side tail booms are developed and end with parts turning on the horizontal axis. On the wing consoles, which have a large sweep, there are swivel socks and internal and external elevons. The tail assembly is V-shaped, the consoles of which are all-moving, performing the function of both horizontal and vertical tail. The air intake is located in the lower part of the fuselage and partially covers it from the bottom side. The technical result is to increase the stability and controllability of the aircraft without deteriorating the characteristics of radar visibility. 5 z.p. f-ly, 3 ill.
The invention relates to the field of aviation, in particular to light tactical aircraft with low radar visibility.

A supersonic convertible aircraft is known from the prior art (see patent RU 2432299 C2, published on October 27, 2011), which contains a fuselage with a lower air intake and a V-tail.

However, the design of the known aircraft has the disadvantage of insufficient stability and controllability of the aircraft, as well as a sufficiently large radar visibility.

The prior art also known aircraft Lockheed F-117А Nighthawk with low radar visibility, made according to the scheme "tailless with a V-tail" without horizontal tail. On the wing of the known aircraft there are deflectable elevons. Pitch and roll control is carried out by elevons, yaw - by all-moving vertical tail.

However, the disadvantage of this aircraft is poor takeoff and landing characteristics, as well as insufficient stability and controllability of the aircraft.

The objective of the claimed invention is to eliminate the shortcomings of aircraft known from the prior art.

Thus, the technical result, to which the claimed invention is directed, is to increase the stability and controllability of the aircraft without deteriorating the characteristics of radar visibility.

Light tactical aircraft contains a fuselage with side tail booms, wing panels, tail, air intake, power plant and jet nozzle. The side tail booms are developed and end with parts turning on the horizontal axis. On the wing consoles, which have a large sweep, there are swivel socks and internal and external elevons. The tail assembly is V-shaped, the consoles of which are all-moving, performing the function of both horizontal and vertical tail. The air intake is located in the lower part of the fuselage and partially covers it from the bottom side.

The rotary jet nozzle is located along the axis of symmetry of the fuselage and is used for control and balancing in flight and is deflectable in the vertical plane.

Rotary jet nozzle is located along the axis of symmetry of the fuselage and is used for control and balancing in flight and is made all-aspect.

The axes of rotation of the consoles of the V-tail are located perpendicular to the axis of the fuselage.

The axis of rotation of the V-tail consoles are located closer to the leading edge of the consoles.

All edges of the air intake are swept.

Further, the claimed invention is explained in more detail by the drawings, in which:

Fig. 1 - claimed aircraft, top view,

Fig. 2 - claimed aircraft, front view,

Fig. 3 - claimed aircraft, side view.

The claimed light tactical aircraft contains a fuselage (1) with developed side tail booms (2) and an air intake (10) of the power plant, wing consoles (3) and a V-tail (4). The air intake (10) is located in the lower part of the fuselage (1) and partially covers it from the bottom side (see Fig. 2). Wing consoles (3) are made of large sweep (40-55°) and have deflectable wing tips (6). On the trailing edge of the wing console (3) there are internal (7) and external (8) elevons. The side tail booms (2) end in turning parts (5), which act as elevators. V-shaped tail (4) is made all-moving simultaneously plays the role of horizontal and vertical tail, and provides the ability to control the aircraft in the longitudinal channel with in-phase deviation and in the transverse channel with differential deviation, and also provides stability and controllability in the track channel at all flight speeds and provides the function of air braking. Road stability at supersonic flight speeds with insufficient static stability is provided artificially, due to the deflection of the consoles V-tail (4). When a disturbance of the atmosphere or a gust of wind occurs in the track channel, the in-phase deviation of the V-shaped tail surfaces (4) in the direction of parrying the disturbance is carried out. This solution makes it possible to reduce the empennage area, thereby reducing the mass and drag of the empennage and the aircraft as a whole.

The axes of rotation of the consoles of the V-tail are located perpendicular to the axis of the fuselage and are located closer to the leading edge of each console.

Wing mechanization (3) is used to provide control in the pitch and roll channels, to increase lift. The rotary toe (6) of the wing is used to increase the critical angle of attack and ensure a shockless flow around the wing (3), for flight "along the polar envelope" in the takeoff, landing, maneuvering and cruising subsonic flight modes. The elevons (7, 8) are designed to control the aircraft in pitch by in-phase up-down deviation, to increase lift during in-phase downward deviation in various modes by increasing the curvature of the wing median surface, and to control roll in case of differential deviation. When providing the air braking function, the elevons (7, 8) deviate together with other organs in such a way that

The rotary parts (5) of the side tail booms, when deflected up and down, are used for pitch control, performing the functions of an elevator, in takeoff and landing modes they serve to compensate for the dive moment that occurs when the elevons (7, 8) are deflected to increase the wing lift. When providing the air braking function, the rotary parts 5 deviate together with other bodies, providing an increase in resistance and a zero increment in the total pitching moment.

The execution of all edges of the air intake swept provides a reduction in the level of radar visibility of the aircraft.

Rotary jet nozzle (9) of the aircraft engine is located along the axis of symmetry of the fuselage and is used for control and balancing in flight;

All available controls (V-tail, wing tips, elevons, rotary parts of the beam) while deflecting increase aerodynamic drag, thereby performing the function of brake flaps.

The presence of all the above controls in the design of the aircraft together make it possible to move the zones of occurrence of unbalanced static instability of the aircraft in the longitudinal and track control channels to the range of angles of attack of 15 ° or more, to increase the bearing properties and reduce the resistance of this aerodynamic layout of the aircraft, which is confirmed by calculations and testing the model in wind tunnels, and allow us to have operational angles of attack, the level of aerodynamic quality, providing a significant improvement in cruising, maneuvering and takeoff and landing characteristics compared to known analogues.

Given the layout of a light tactical aircraft due to the claimed design provides maximum controllability of the aircraft in any flight modes and does not increase the radar visibility of the aircraft.

Claim

1. A light tactical aircraft containing a fuselage with side tail booms, wing consoles, tail assembly, an air intake, a power plant and a rotary jet nozzle, characterized in that the side tail booms are developed and end with parts turning on a horizontal axis, on wing consoles having large sweep, swivel socks and internal and external elevons are located, and the tail unit is V-shaped, the consoles of which are all-moving, performing the function of both horizontal and vertical tail, and the air intake is located in the lower part of the fuselage and partially covers it from the underside.

2. Light tactical aircraft according to claim 1, characterized in that the rotary jet nozzle is located along the axis of symmetry of the fuselage and is used for control and balancing in flight and is deflectable in a vertical plane.

3. Light tactical aircraft according to claim 1, characterized in that the rotary jet nozzle is located along the axis of symmetry of the fuselage and is used for control and balancing in flight and is made all-aspect.

4. Light tactical aircraft according to claim 1, characterized in that the axis of rotation of the consoles of the V-tail is perpendicular to the axis of the fuselage.

5. Light tactical aircraft according to claim 4, characterized in that the axis of rotation of the V-tail consoles is located closer to the leading edge of the consoles.

6. Light tactical aircraft according to claim 1, characterized in that all edges of the air intake are swept.

 

[Trident]

Seems to show a F-35-like dorsal brake parachute pod, interesting! The lack of one on the mock-up seemed a strange departure from Russian land-based fighter traditions.

BTW, the original figures from the Checkmate patent are almost exactly to scale with the full-size T-50 patent drawings:



Pretty remarkable how the relative positions of the fins and cockpit are apparently within a few centimetres on both aircraft!

 

[trose213]

https://twitter.com/i/web/status/1509886777242365977

View: https://twitter.com/theF35JPO/status/1509886777242365977

 

[FighterJock]

https://twitter.com/i/web/status/1509886777242365977

View: https://twitter.com/theF35JPO/status/1509886777242365977

Is that the F-35 program office having fun because it is April Fools day by any chance?

 

[trose213]

Is that the F-35 program office having fun because it is April Fools day by any chance?

Nah, the F-35 just chose to dominate every domain, real or imaginary.

 

[Bounce]

So does anyone know if the LTS will continue now with the sanctions hitting chips etc? Was looking forward to seeing a flying prototype.

 

[Cannonfodder43]

Nobody knows. There have been reports of certain factories and such halting production due to lack of imported parts but I am skeptical of those (typically Ukrainian or Western) claims.

Until we get hard evidence I am assuming things are carrying on as normal as can be

 

[fightingirish]

I wouldn't be surprised, if Argentina would halt their fighter procurement for the foreseeable future. Any other modern fighter (i.e. Rafale) as an alternative to the Sukhoi LTS has parts made in the UK.

 

[kaiserd]

Seems extremely unlikely Argentina or anyone else not already deeply isolated from the wider “western” world will be buying the LTS or anything else Russian in the foreseeable future.

 

[stealthflanker]

Apparently Sukhoi also submit patent for LTS here in Indonesia.


Similar thing happened to that French "Belharra" class, also saw the patent submission here.

 

[flateric]

...

 

[flateric]

...

 

[riggerrob]

Given that LTS is supposedly based upon "proven" SU-57 technology makes it a tough sell to potential Second-World and Third-World customers. To date, SU-57 has only been built in the dozens and has only flown one or two days worth of combat missions in Syria. No SU-57 have been reported in Ukrainian skies.

 

[Acatomic]

@stealthflanker

Any more pictures of the unmanned version from that patent application?