Sukhoi LTS "Checkmate" #2

Broski wrote:

RTN wrote:How does a Russian OTH radar placed in Russia help to detect targets in Syria or Afghanistan?

Voronezh-DM (77Ya6-DM) works in the decimeter range (UHF) and was designed by NPK NIIDAR. It has a range of up to 10,000 km and is capable of simultaneously tracking 500 objects.

https://en.wikipedia.org/wiki/Voronezh_radar

Armavir Radar Station is an early warning radar station near Armavir in Krasnodar Krai, Russia. It is a key part of the Russian early warning system against missile attack and is run by the Russian Aerospace Defence Forces. There are two radars here - one faces south west and one south east. They provide radar coverage of the Middle East.

https://en.wikipedia.org/wiki/Armavir_Radar_Station

Distance between Armavir Radar Station and Syria

Distance between Armavir Radar Station and Afghanistan

Those are radars of the strategic early warning against ballistic targets, they use direct propagation and not ionospheric reflection like the Conteiner, which is the type of radar that allows them to follow aerodynamic targets flying low altitude in most of Europe and ME

[quote="Russian_Patriot_"]

Russian_Patriot_ wrote:Chinese copy of the Checkmate?) 
[url=https://servimg.com/v]

Looks straight out of the Mig booth at Maks.

I definitely see more than just one copy over there, Lockheed, Boeing and UAC may feel tad ripped off right about now

JohninMK wrote:Doesn't NORAD, Filingdales and Oman have US made equivalents?

NORAD is testing a OTH radar. Jindalee OTH radar is operational in Australia.

U.S Air Force (AN/FPS-118 OTH-B), U.S Navy ( AN/TPS-71 ROTHR ) have all installed OTH radar.

Isos wrote:Useless. It's not Russia that send its carriers and air force invade other countries. There is no russian or chinese base around US.

Russian and chinese radars are useful because they have hundreds of US and nato bases around them. And western keep saying they should attack them.

LOLzzzz... The only thing useless, is your comment.

If "hundreds of US and nato bases" are around them why do they need a OTH radar. Any ground based radar would do

RTN wrote:LOLzzzz...   The only thing useless, is your comment.

If "hundreds of US and nato bases" are around them why do they need a OTH radar. Any ground based radar would do

The amount of BS you have accumulated in the last few days is already sensational and you still keep committed to improve on that, respect!

It is pretty clear who the aggressor is... the Russians have carefully built up over time an IADS network and SAM range as well as sensors and aircraft etc etc to defend Russia. They have a complex layered defence that can detect threats thousands of kms away from their current borders meaning attacks will be detected early and can be confronted well outside Russian territory... so a flight of C-17s launching swarm attacks from the EU will result in tactical nukes to take down those swarms over Poland and the Baltic states most likely, with follow up strikes against Brussels and the US for ordering it.

The west does not need self defence stuff because there is no one to attack them, they need AWACS based attack and defence so they can deliver aggression around the globe when they need to and they seem to need to all the time.

They are the pinnacle colonial power who sees the rest of the world as their dominion... the west is not as appealing as it once was.

I think the US equivalent was not really a serious competitor... have read western expert opinion that the maker of the F-32 was just using the programme money to test new stealth technology they could apply to bombers and never really expected to win.... which is why the F-35 was so bad and such a lazy programme I guess because there was not much in the way of real competition.

I would reserve judgement on manouver performance till I see the Checkmate in the air, but despite having a similar layout to the American design it is a significantly slimmer aircraft... I am trying to keep an open mind... the checkmate certainly has enormous potential for the future.

GarryB wrote:
I would reserve judgement on manouver performance till I see the Checkmate in the air, but despite having a similar layout to the American design it is a significantly slimmer aircraft... I am trying to keep an open mind... the checkmate certainly has enormous potential for the future.

One concern that I have with the maneuverability outlook for the Checkmate is the positioning of the intake. Modern military avionics relies on negative stability for higher maneuverability. That means the flight surfaces don't tend to settle on a preset 'local minimum' profile, as with commercial aircraft but rather tend to veer away, almost like car wheels out of alignment. The overall weight and thrust distribution along the axis (specifically longitudinal) is also important.

One requirement, if I remember correctly, is locating the intake and thrust points as close to the mid section of the aircraft as possible, somewhat like the flankers (which, by the way, are the best unstable tri-plane designs out there). This tends to reduce the overall natural pitch stabilization that any aerodynamic object may tend to settle on.

With an intake so far to the front, the Checkmate might lose some of its longitudinal instability. My guess is that Sukhoi might have prioritized stealth over performance here.

Daniel_Admassu wrote:

GarryB wrote:
I would reserve judgement on manouver performance till I see the Checkmate in the air, but despite having a similar layout to the American design it is a significantly slimmer aircraft... I am trying to keep an open mind... the checkmate certainly has enormous potential for the future.

One concern that I have with the maneuverability outlook for the Checkmate is the positioning of the intake. Modern military avionics relies on negative stability for higher maneuverability. That means the flight surfaces don't tend to settle on a preset 'local minimum' profile, as with commercial aircraft but rather tend to veer away, almost like car wheels out of alignment. The overall weight and thrust distribution along the axis (specifically longitudinal) is also important.

One requirement, if I remember correctly, is locating the intake and thrust points as close to the mid section of the aircraft as possible, somewhat like the flankers (which, by the way, are the best unstable tri-plane designs out there). This tends to reduce the overall natural pitch stabilization that any aerodynamic object may tend to settle on.

With an intake so far to the front, the Checkmate might lose some of its longitudinal instability. My guess is that Sukhoi might have prioritized stealth over performance here.

IIRC, longitudinal static stability has to do with the position of the center of gravity (more forward = more stable), rather than the position of intake and thrust, no?

Lennox wrote:
IIRC, longitudinal static stability has to do with the position of the center of gravity (more forward = more stable), rather than the position of intake and thrust, no?

Well, what is required here is the opposite - instability. That way, the aircraft will always be 'on edge', tending to roll or pitch. This makes it highly agile. In older generation aircraft it would be too much work for the pilot to constantly compensate with manual controls and thus was not implemented. But with computerized flight and envelope control, it has successfully been used on fighter jets.

The weight distribution requirement for instability is not fully determined by the center of gravity alone. Rather, most of the weight itself should be concentrated as close as possible to the CoG. And that center should be midway between intake and exhaust, not the geometrical center of the plane. That being said, this is the ideal condition. I don't think any design has achieved it since other priorities exist for fighter aircraft other than flight performance.

Daniel_Admassu wrote:Well, what is required here is the opposite - instability. That way, the aircraft will always be 'on edge', tending to roll or pitch. This makes it highly agile. In older generation aircraft it would be too much work for the pilot to constantly compensate with manual controls and thus was not implemented. But with computerized flight and envelope control, it has successfully been used on fighter jets.

The weight distribution requirement for instability is not fully determined by the center of gravity alone. Rather, most of the weight itself should be concentrated as close as possible to the CoG. And that center should be midway between intake and exhaust, not the geometrical center of the plane. That being said, this is the ideal condition. I don't think any design has achieved it since other priorities exist for fighter aircraft other than flight performance.

My two cents:

instability in the longitudinal axis allows the plane to be unsettled easier of course, but also and very importantly, to add the lifting surface of the tail instead of subtracting it during all but most tight sustained turns, because the plane has a natural tendency to raise the nose and it does not need downforce generated at the tail to be kept stable or even to make it turn, this can be seen in the airshows with the Su-57 for intance. So turning is substantially improved. That configuration allows also lower drag and higher ceiling, among other advantages.

This instability is determined mainly by the relative positions of the CoG and CoL, the later being after the first in stable planes and the other way around in unstable ones (supersonic flight changes this of course). I have never heard the intake has much to do with that, but maybe I am missing some relevant effect there?

One concern that I have with the maneuverability outlook for the Checkmate is the positioning of the intake. Modern military avionics relies on negative stability for higher maneuverability. That means the flight surfaces don't tend to settle on a preset 'local minimum' profile, as with commercial aircraft but rather tend to veer away, almost like car wheels out of alignment. The overall weight and thrust distribution along the axis (specifically longitudinal) is also important.

I would say its manouver potential looks no worse than for the F-16 which is rather good... with all round vision systems and thrust vectoring missiles like R-73 and R-74 and presumably 9M100, getting on someones tail before launching is not likely to be so critical as it once was...

The MiG model looks similar but with canards, so perhaps they put more emphasis on ability to point the nose...

With an intake so far to the front, the Checkmate might lose some of its longitudinal instability. My guess is that Sukhoi might have prioritized stealth over performance here.

Not sure what the intake has to do with stability or otherwise of any aircraft... the engine exhausts of course make sense, but the intakes?

Well they advertize it as a 8g aircraft when other 4.5 gen fighter are 9g abd can even go to 12g if really needed.

But who care it will be good to launch missiles against f-15/typhoon/f-18 in bvr without being detected at long range, still more manoeuvrable than f-35 and can drop pgm for the price of 20 million $.

That's still exeptional.

I would say reduced manouver performance requirements and top speed requirements will likely be the foundation of the reduced costs to buy and to use the aircraft... so probably well worth it.

Nobody is likely to be dodging modern missiles, but then you wont need to waste time and fuel getting on to the tail of an enemy aircraft for a launch in the first place anyway.

IIRC, longitudinal static stability has to do with the position of the center of gravity (more forward = more stable), rather than the position of intake and thrust, no?

Cg and thrust would be relevant I would think... but assuming it does not get suffocated in a high AOA manouver, the intake is not so important in stability terms AFAIK.

Well, what is required here is the opposite - instability. That way, the aircraft will always be 'on edge', tending to roll or pitch. This makes it highly agile. In older generation aircraft it would be too much work for the pilot to constantly compensate with manual controls and thus was not implemented. But with computerized flight and envelope control, it has successfully been used on fighter jets.

I remember reading about it in the 1980s... one western expert described it and holding the handle bars of a bicycle while sitting on the bonnet of a car with the bicycle rolling backwards and you having to make hundreds of tiny corrections to keep it going straight... would be impossible for most humans at any decent speed, but it means if you need to turn the turn will start immediately without having to overcome its natural stability which in effect is wanting to continue to fly the way it is flying.

In theory it should give advantages in a turning fight but as speed bleeds manouver performance based on conventional control surfaces degrade and slow down whereas thrust vectoring forces remain effective and responsive...

Rather, most of the weight itself should be concentrated as close as possible to the CoG. And that center should be midway between intake and exhaust, not the geometrical center of the plane.

There are lots of factors involved I suspect... especially with swing wing aircraft, but the cg can move depending on altitude and flight speed as well...

Other factors include fuel weight and distribution and weapon payload location before and after an attack... no point achieving ideal combat manouver performance after you have dumped all your fuel and weapons...

Lets see it in the air before we make any judgements... it might surprise us, but even if it doesn't... the MiG-21 was not a super manouverable fighter either.

UAC plans to show the new Checkmate fighter at foreign air shows

The Checkmate light single-engine fighter of the fifth generation is planned to be demonstrated to potential customers at exhibitions abroad, said the head of the United Aircraft Corporation (UAC) Yuri Slyusar.
"Judging by the visits of delegations to the pavilion (at MAX), the interest is very great. And, of course, we will now carry this plane to exhibitions if they return to the usual offline mode," Slyusar said in an interview with Vedomosti newspaper.
He confirmed plans to carry out the first flight of the new fighter in 2023.
"This aircraft as a platform implies both a two-seat, optionally manned, and unmanned versions. We hope that this approach and modification options will interest our key customer," said the head of the UAC, answering the question whether the Russian Defense Ministry will order Checkmate.
According to him, over time, the new Sukhoi aircraft may be equipped with a "second stage" engine for the Su-57. This "product 30" engine will allow the fighter to develop supersonic speed without afterburner.

https://www.militarynews.ru/story.asp?rid=1&nid=558943&lang=RU

Further hints about the underlying plans of both UAC and VKS for the supply of LTs to the Russian armed forces

As said before, I assume that the LTS is the key plane to modernize and make the VKS grow, and also that it is in fact designed around the izd. 30, which would allow 5th gen performance together with standard overload characteristics, and maybe an internal cannon

Kiko wrote:
Russia is also planning to participate in the flying program, the minister said.

https://tass.com/defense/1357149

The Su-35 no doubt and maybe a Su-57.

This from the interview with Slyusar:

– The UAC developed the Checkmate fighter presented at MAX on its own initiative, right?

– Yes, the fighter concept was proactively proposed a year ago. Then the president supported it. We were instructed to speed up, and we did. Therefore, in a year, thanks to digital design methods and the use of supercomputer technologies, we managed to create a new aircraft. Documentation was developed, units were manufactured, and assembly was carried out. The plane that we showed at the air show is not just a demonstrator or prototype, it is a real sample. We hope to launch our first flight in 2023.
– Have foreign customers already managed to evaluate the aircraft?

– Judging by the visits of delegations to the pavilion [on MAKS], the interest is very high. And, of course, we will now carry this plane to exhibitions, if they return to the usual offline mode. We believe that this aircraft – for us at least-is a revolution in design, in customer relations, and in the organization of after-sales services.
– Will the Ministry of Defense order it?

– This aircraft as a platform implies both a two-seat, and optionally manned, and unmanned versions. We hope that our key customer will be interested in this approach and modification options.
– Do you plan to use the engine of the second stage – "product 30" – for this aircraft in the future?

- Over time. Aircraft and engines often live in different life cycles. Sometimes the same engines are put on several aircraft. Sometimes several engines are put on one plane. This is a natural process. But, of course, we will consider the engine of the second stage for this aircraft, too, not only for the Su-57.
– The Ministry of Industry and Trade did not participate in financing the development of this aircraft?

– This is an initiative development, but we hope for the help of the Ministry of Industry and Trade. Of course, we need government support in creating this product and this platform.
– How much money may be required to start production?

– There is already a figure, but we are not sure that we can name it. Let's just say: it is quite reasonable. We use in the new car the existing advanced reserve created in the framework of various other design developments, not only the Su-57. Therefore, there are no mega-expenditures for testing here.

https://www.vedomosti.ru/business/characters/2021/10/18/891601-oak-konfederatsii