Sukhoi Su-57 flight testing, development & operations [2012-current]

[Life of Tyo]

It,s T-50KNS before modif to Su-57E , Zvevda TV 2018

 

[Stormingart]

Wait how is the Su-57E different from the regular Su-57? I can’t really find anything different about it.

I assume it just means Russia is offering to modify it slightly per buyer’s request?

 

[FighterJock]

So I would think that the Su-57E will end up being like the Su-30MK series of Flankers where each country could modify their own variant to suite their individual needs such as India, China and Vietnam.

 

[Scorpion82]

The Su-57E is the export model of the Su-57. It doesn't mean that customers will be allowed to request/implement changes themselfes. The era where aircraft like the Su-30MKI were developed was different to the situation we have now. Most likely the Su-57E has some export specific radios, IFF etc., incl. some downgrading as it has been common practise with export versions of Russian aircraft, like the Su-27SK, Su-30SME, MiG-29B etc.

That with two to three dozen production airframes they aren't going to sent these to airshows is understandable. They certainly need the operational airframes for operational duties. And yes an F-35 with about 1000 or so airframes built is an entirely different story.

That being said, the Russian approach to the 101KS Atoll differs a great deal from the American approach for the F-35's EO suite. The Americans have packaged more functionality into fewer systems, the Russians have packaged it into much more systems. Whether the Russians did that as they are lagging technically behind, or for the benefits of dedicated sensors for specific purposes is speculative, albeit the historical track record is in this respect more pointing towards the former rather than the latter.

 

[FighterJock]

So no more options for export customers then Scorpion82? Pity that.

 

[Scorpion82]

So no more options for export customers then Scorpion82? Pity that.

I wouldn't rule that out in general, but as said the situation in the 90s was quite different and the survival of the Russian arms industry highly dependent on export sales.

 

[alberchico]

F-35 or Su-57: India's billion-dollar fighter jet face-off

India faces a crucial choice in modernising its air force. But is a cutting-edge US fighter jet the answer?

www.bbc.com

 

[Anduriel]

So no more options for export customers then Scorpion82? Pity that.

On Su-57 it's unlikely, but S-75 might have such option, as that's what they said in the first presentation.

 

[FighterJock]

So I would expect more countries going for the Su-75 instead of the Su-57 as that would be a much better option than being stuck with export equipment on the Su-57.

 

[Arjen]

Su-75 will have to fly first.

 

[Red_air]

So I would expect more countries going for the Su-75 instead of the Su-57 as that would be a much better option than being stuck with export equipment on the Su-57.

If 6 years have passed from the su57 prototype to its flight model (2004-2010), then the su75 should fly sometime in 2026-2027 and another 10 years for refinement. Okay, we can assume that using ready-made components from the Su57 will speed up this process twice, it turns out that the Su 75 will be ready sometime in 2032-2035 and it will take about 5 more years to increase production. It turns out that the su75 is the aircraft of the 40th year. I don't think anyone will wait that long. There's nothing to choose from

 

[FighterJock]

The Su-75 being ready sometime in 2032-2035? That is a long time to wait.

 

[Ainen]

The Su-75 being ready sometime in 2032-2035? That is a long time to wait.

Realistically it's the date. We are already in 2025, and it's abundantly clear commercial aircraft won't get dozen aircraft for intensive trials campaign.

 

[Airborne2001]

The Su-75 being ready sometime in 2032-2035? That is a long time to wait.

I think the Su-75 is likely to fly this year. The export sale to Algeria is definitely gonna give Sukhoi a boost economically (and in general), and they sound pretty confident on getting it to happen this year. Of course, anything can happen.

EDIT: To specify, I am referring to the first flight and not production/operational service.

 

[Stormingart]

Russia stated the Su-57M will be produced this year and that the Su-75 will receive its first flying prototype this year.

 

[F-14ATomcat]

Russia stated the Su-57M will be produced this year and that the Su-75 will receive its first flying prototype this year.

I am looking forward to the flight of SU-75, I think that will be a modern MiG-21

 

[Ainen]

I am looking forward to the flight of SU-75, I think that will be a modern MiG-21

It's a bit large for that. Basically as large as F-35.
In Russian terms, it's more of a Su-17 follow on.

 

[Stormingart]

There is already a modern MiG-21 anyways. It’s called MiG-35.

 

[overscan (PaulMM)]

There is already a modern MiG-21 anyways. It’s called MiG-35.

Nope. MiG-29 is too big to be a modern MiG-21.

The rot set in with the MiG-23. There was a faction in Mikoyan opposed to increasing the size then, but the VVS requirements were impossible to reconcile with a MiG-21-sized fighter.

 

[Ainen]

There is already a modern MiG-21 anyways. It’s called MiG-35.

It is not by an means.

Mig-35 also in the very same 25-30t class, using x2 engines. It may be affordable to procure due to exchange rate pressure on ru economy, but sustaining it is not cheap by any means.

It's also, like any other legacy platform, on shaky capability level, being over 40 years old. Modern electronics can't substitute Vlo airframe.

 

[F-14ATomcat]

It's a bit large for that. Basically as large as F-35.
In Russian terms, it's more of a Su-17 follow on.

I meant it is single engine with a U type intake with DSI technology, I meant a modern MiG-21 since compared to the Su-57 which is a Su-27 replacement.

Any way do not worry I want to see it flying

 

[Joint Soviet Fighter]

That being said, the Russian approach to the 101KS Atoll differs a great deal from the American approach for the F-35's EO suite. The Americans have packaged more functionality into fewer systems, the Russians have packaged it into much more systems. Whether the Russians did that as they are lagging technically behind, or for the benefits of dedicated sensors for specific purposes is speculative, albeit the historical track record is in this respect more pointing towards the former rather than the latter.

I actually don't believe that to be the case in this particular instance, as it appears to be more of a poor design choice.

 

[totoro]

MiGs project 33 was closest thing to a modern mig-21. A single engine scaled down Mig-29. Since it's using the same engine, and is roughly of same size, I guess JF-17 would be the closest thing to a modern MiG-21.

 

[Joint Soviet Fighter]

It's also, like any other legacy platform, on shaky capability level, being over 40 years old. Modern electronics can't substitute Vlo airframe.

This would make much more sense if we were talking about The F-15, F-16, F-18, Eurofighter Typhoon, Gripen, or Rafale, imo, as those airframes don't allow for any transformative modifications, whereas with The MiG-29 & Su-27/Su-30/Su-34/Su-35, the sheer space between the nacelles, alone, means that all of those planes can be upgraded so as to keep them competitive for many years to come, & let's face it - reconfiguring/reshaping said aircraft into low observable platforms would cost far less money, not take nearly as much time to manufacture, & would be considerably more realistic for Russia as opposed to waiting another 15 years on The Su-75.

Additionally, given the continued widespread use of Fulcrums & Flankers, they'd make an absolute fortune on such upgrade programs, at which point that money could then be used on something like The Checkmate. Just look at India. Is it realistic to expect them to actually be able to acquire The F-35, let alone in sufficient numbers, in order to counter China's ever-growing stealth fleet? No. Could Russia supply them with enough Su-57s for the same purpose? I very much doubt it, especially in short order, but India's Air Force currently operates over 250 Su-30MKIs & more than 50 MiG-29s, so it's something to think about. Maybe.

 

[Squirrel]

Front IRST unit of Su-57, 101KS-V most likely not dual band because windows transparent to LWIR are usually germanium which is a dark color and opaque in visible spectrum, or for dual-band MWIR/LWIR, zinc selenide which is yellow color also mostly opaque in visible spectrum. While the 101KS-V bulb is clear and transparent in visible spectrum which probably means MWIR only system.

The L-band IFF antennas aren't unique to Su-57, similar to Band 2 arrays on other fighters.

Hi ! 101KS-V bulb/dome is not so clear like old OLS-27 or newer OLS-30/35 'cause it has that 'yellowish/golden cover' .Now the question is ,is it only the RAM for reducing frontal RCS or maybe the material used for transparency of the MWIR/LWIR band.
Many sources mention that 101KS-V (OLS-50M) is based on so called QWIP technology and that it uses LWIR (8-12μm) band of the IR radiation.Maybe,maybe.... but here is some interesting comment about that topic from David Trapp on Quora :

Has long wave long range IRST defeated stealth?

https://www.quora.com/Has-long-wave-long-range-IRST-defeated-stealth

Photos of the 101KS-V :

101KS-V

Combat Identification & Photography

www.recomonkey.com

Btw, decimetric L-band AESA N036L (four pcs) are the real search-detect-track radars and not only for the IFF/ID.

@ siegecrossbow​

''It carries like three luneburg lenses…''

Take a look on the Luneberg lenses under the Su-57's wing...



@Ainen

''N036L arrays are radars first, IFF and EW on top.''

That's right.

''Simple anwer is that it is most certainly not used for fire control.
L band isn't fire control band, it's airspace control band.''

Absolutely.

Now some technical details about those low-frequency/long-wave ,decimetric radars known as N036L of the Su-57 as the first ever to be used on one fighter. L-band AESA radar for the Su-57 is developed some 20 years ago under the Project called ''The scale'' (шифр «Мерило»).One of the main goals was to detect and track stealth aircraft from the very long distances because decimetric L band as we know is used for the long-range search.Besides this Project there was another one called ''Horseshoe M1'' (Подкова-M1) and the result of this project were special waveguide/radiating units. Radars N036L are part of the unique dual-band radar system N036 Byelka (Squirrel) part of the higly integrated and automated combat complex called Sh121 MIRES.

Su-57 has in fact four low-frequency,long-wave L-band /f=1.28-1.55GHz, λ=24cm/ AESA's that are positioned in the next places: two in LEVCON's and two in wingslats consoles. They are linear 2D (not 3D) radars where aircraft can be tracked by two angular coordinates in the air space : distance and azimuth. Btw ,missing elevation data can come via data-link from other aerial/ground assets. It is interesting that those L-band AESA can function as L -band PESA also. L-band AESA has 1.6m wide antenna with three very big /heavy four-channeled TRM's where every channel has max output signal power several of hundreds of W's. Each channel has its own task : channel No1 is for the international IFF ( NATO standard ,Mk12) , channel No2 is for the long-range radar search and long-range detection/track especially of the stealth aircraft,channel No3 is for the domestic IFF ( part of the N036Sh Pokosnik/Reaper system) and channel No4 is for the ECM/jamm in decimetric band ( jamming of enemy L-band assets ). For the real long-range search-detect-track radar mode it works in 1.28GHz-1.44GHz frequency range.For the IFF it works in 1.44GHz-1.55GHz frequency range.

Radar envelope in azimuth of L band AESA is 110° ( +/-55° ) with beam width in elevation 70°-90° . Each L-band AESA has two rows of radiating elements ( waveguides). One upper is used when LEVCON's and wingslats are in down position and lower one can be used when LEVCON's and wingslats are in neutral position. L-band AESA can be used for the search of airspace as wrote especially for long range detection of any stealth aircraft and it is the real so called ''gamechanger''.
I've found some 'radar rules' and maybe someone can explain them,tnx : ''The greater the radar signal wavelength is ,the greater is the detection distance'' and ''The thickness of an illuminated aircraft's skin must be equal to half the wavelength of the radar signals that illuminate that skin.'' Btw, I 've found some additional info that L-band PESA/AESA can work in so called Bi-static mode.

Now this material is very very interesting .I had complete translation of all pages but unfortunately I lost it.This is transl. of the first page only.

''Technical specifications ,requirements and development work
"Development of the technology, algorithms and hardware for assessing and adjusting the amplitude-phase characteristics and radiation patterns of the PESA/AESA and their elements during the creation and serial production of the search radars", code "The scale ".

1. The role and the place of the topic in solving problems in the sphere of the state interests.

Currently, IFF/interogator antennas are located in the nose compartment either on the aperture of the airborne radar antenna (BRLS) or outside it. Placing long-wavelength emitters on the radar antenna aperture entails a decrease in the radar radiation characteristics.Installation of L-band emitters in the nose compartment outside the radar aperture due to the limited midsection of the aircraft leads either to low characteristics of the interogator or to a sharp reduction in the size of the radar antenna aperture to form an acceptable-sized phased array / aerial phase array of the interogator and, as a consequence, deterioration of the radiation characteristics of the PESA/AESA.Thus, finding the possibility of creating basic manufacturing technologies and means of assessing the amplitude-phase characteristics and directional patterns of L-band PESA/AESA in deflected wing tips is a task that is relevant and in demand for the new generation of the complex of aircraft equipment.
The novelty of the work lies in the development and introduction into production of new modern basic technologies for the manufacture of the PESA and AESA in L-band located in the deflectable wing tips, the functional units included in them, as well as technologies, algorithms and hardware for setting up and evaluating the characteristics of PESA/AESA which will provide the ability to implement IFF and search-detect-track radar modes in the decimeter wavelength range.
Existing domestic technologies for creating PESA/AESA and especially airborne PESA/AESA do not fully correspond to the modern world level, which does not meet the interests of ensuring state security when solving problems of determining the nationality of the air, ground and water objects using airborne radar over long distances (about 300-400 km).
This development will make it possible to achieve the specified characteristics of the PESA/AESA for the IFF, characteristics of modern aviation complexes, to expand their functionality in terms of operation in the real radar mode with the prospects of radar (search,detect,track) operations against the stealth aircraft. In addition, the introduction of developed modern technologies will increase the competitiveness of military equipment in the foreign market and, as a result, will lead to the development of domestic production and increase the number of jobs.''

Article on 13 pages is on Word.Is there possibility for transferring article here or maybe it already exists on 'sp. forum'?

Now some pics and details .It is interesting to note that first public showing of the L-band antenna for the Su-57 was on MAKS2007. Red lines show us those very big/heavy TRM's



As mentioned before, linear 2D L-band PESA/AESA radar has two rows of radiating elements.





Radiating elements ....Three TRMs has its own radiating block with 4 pcs for every working channel.


In his article from 2009 famous Dr. Carlo Kopp mistakenly wrote that this L-band antenna is planned for Su-27/30/35.

Assessing the Tikhomirov NIIP L-Band Active Electronically Steered Array

APA Analysis Paper APA-2009-06; Title:Assessing the Tikhomirov NIIP L-Band Active Electronically Steered Array; Abstract:Tikhomirov NIIP in Moscow are developing an L-band AESA radar system intended for embedding in the leading edges of fighter wings. A demonstrator of the L-band AESA subsystem...

ausairpower.net

Actually he was guided by this advertisments with wrong pictures of the fighters...

File:AESA L NIIP maks2009.jpg - Wikipedia

en.m.wikipedia.org

As we know, Su-35S got this ....




Now some details of those TRM's. It is interesting that average and max output pulse power of the each channel was increased over time.Some citations:

Data before 2010:

''Сегодня ФГУП "НПП "Пульсар" создает изделия, отвечающие самым высоким требованиям. К ним относятся:
• не имеющий аналогов, сверхширокополосный четырехканальный приемо-передающий модуль L-диапазона (1–1,5 ГГц) с выходной мощностью 200 Вт на канал для РЛС с активной фазированной антенной решеткой (АФАР), объединяющий функции госопознавания, международного опознавания и обзорной РЛС и размещаемый в крыле са-
молета (рис.1). Модуль отличается рекордно малыми габаритами и характеризуется высоким отношением выходной СВЧ-мощности к объему (2 кВт/л) . Он позволит поднять энерговооруженность перспективных РЛС с АФАР, предназначенных для самолетов пятого поколения;''



Data from 2010/2011:

''МОДЕРНИЗАЦИЯ МОЩНОГО МОДУЛЯ БОРТОВОЙ АФАР L-ДИАПАЗОНА

Модуль первичной разработки был представлен на конференции «Пульсар-2008», сейчас он осваивается в производстве. Вопрос о его модернизации – ответ на требование оперативного повышения уровня эксплуатационных характеристик, что свойственно быстро развивающимся
областям техники.Главная цель модернизации – повышение уровня выходной импульсной мощности с 400 Вт до 700 Вт в рекордной полосе частот 1 -1,5ГГц в каждом из 4-х каналов модуля. При этом габаритные и присоединительные характеристики модуля остаются неизменными.В основе модернизации – новое поколение интегральных сборок под
названием «усилитель мощности» взамен мощных СВЧ транзисторов, а также развитие принципа объемной интеграции. Модернизированный модуль является приемопередающим устройством с коэффициентом шума в заданной полосе не более 4 дБ. Рассмотрен вариант конструктивной модернизации корпуса с целью повышения технологичности сборки, контроля и ремонтоспособности. По параметру удельная выходная импульсная мощность на единицу
объема модуля полученный результат (2 кВт/л) превышает известные мировые достижения.''

''ЭЛЕКТРИЧЕСКИЕ И ФУНКЦИОНАЛЬНЫЕ ХАРАКТЕРИСТИКИ МОДЕРНИЗИРОВАННОГО МОДУЛЯ ДЛЯ БОРТОВОЙ АФАР L – ДИАПАЗОНА

И.В. Коренков
ФГУП «НПП «Пульсар», г. Москва
Разработанный и поставляемый заказчику модуль отличается высоким уровнем выходной мощности (400 Вт на один канал), широкой полосой пропускания (1 – 1.5 ГГц), высокими функциональными возможностями. Главные из них: высокая чувствительность в режиме приема (коэффициент шума менее 4 дБ), наличие вторичного источника питания (ВИП) с высокими показателями стабилизации напряжения, многоуровневый встроенный контроль, обеспечение работы в широком диапазоне температур (от –60 до +70 0C), управление фазой принятого и передаваемого сигналов.
В ходе производства и эксплуатации модуля возникло требование повысить выходную мощность каждого канала с 400 до 700 Вт. Одновременно с этим заказчик отказался от функции «эквивалент антенны».''

From one interview with Yuriy Beliy:

''Использование L-диапазона в работе РЛС в режиме "воздух-воздух" является основным средством обнаружения малозаметных самолетов у Т-50. По словам директора НИИП Юрия Белых, последняя РЛС Н036, выпущенная опытном производством института, установлена на самолете Т-50-9. Будущие самолеты будут оснащаться РЛС производства АО "Государственный Рязанский приборный завод".''

Data from the static tests undertaken about 20 years ago :

http://www.niimp.ru/files/library/Radiotechnology.pdf

http://www.niimp.ru/files/library/Opit%20razrabotki%20i%20osvoeniya%20v%20proisvodstve.pdf

Details from the MAKS2009 :

''На авиасалоне МАКС-2009, на стенде НИИ приборостроения имени Тихомирова, будет демонстрироваться еще и АФАР L-диапазона. Предназначенная для установки в отклоняемые носки крыла истребителя. Она тоже выполнена на современных гибридно-интегральных отечественных технологиях и обеспечивает электронное сканирование лучом в широком секторе углов по азимуту и в широкой полосе частот. Этот локатор, как и АФАР Х-диапазона , собрали в НИИП, где создана для этого уникальная лабораторно-испытательная база, в том числе и оборудованные по последнему слову современной техники безэховые камеры.''

This material is also very interesting to consider ,because it shows us that they used GaN based TRM's.It seems that transmit channel is based on GaN and receive channel is based on GaAS. Question is,are they use this solution in TRMs of the L-band radars of serial/oper. Su-57's.

http://www.niimp.ru/files/library/GaN%20L-band.pdf

 

[Ronny]

Hi ! 101KS-V bulb/dome is not so clear like old OLS-27 or newer OLS-30/35 'cause it has that 'yellowish/golden cover' .Now the question is ,is it only the RAM for reducing frontal RCS or maybe the material used for transparency of the MWIR/LWIR band.

It isn't RAM, it is the micro mesh to prevent radiowave from entering the IRST. Kinda similar to the EOTS

Many sources mention that 101KS-V (OLS-50M) is based on so called QWIP technology and that it uses LWIR (8-12μm) band of the IR radiation.

Every single one of those source are public opinion and some are basically forum member opinion. There is no official source stated that OLS-50 use QWIP or LWIR band

Each L-band AESA has two rows of radiating elements ( waveguides). One upper is used when LEVCON's and wingslats are in down position and lower one can be used when LEVCON's and wingslats are in neutral position. L-band AESA can be used for the search of airspace as wrote especially for long range detection of any stealth aircraft and it is the real so called ''gamechanger''.

L-band wavelength is like 30 cm, element spacing of PESA and AESA are generally half wavelength apart, for the Levcon and wing slat to have 2 row of L band element for beam steering, it need to be like 15 cm thick. I find that hard to believe.

 

[Squirrel]

It isn't RAM, it is the micro mesh to prevent radiowave from entering the IRST. Kinda similar to the EOTS
View attachment 761849


Every single one of those source are public opinion and some are basically forum member opinion. There is no official source stated that OLS-50 use QWIP or LWIR band


L-band wavelength is like 30 cm, element spacing of PESA and AESA are generally half wavelength apart, for the Levcon and wing slat to have 2 row of L band element for beam steering, it need to be like 15 cm thick. I find that hard to believe.

So ,it is micro mesh to prevent radio(radar)wave from entering the IRST . Hm, it is some kind of Radar Apsorbent Material then?

Wavelenght of the N036L PESA/AESA signals is 24cm.There is no doubt that they are real 2D search/detect/track radars.Radars are usually marked with the ''Radiation hazard'' signs.Just like this .

 

[Ronny]

So ,it is micro mesh to prevent radio(radar)wave from entering the IRST . Hm, it is some kind of Radar Apsorbent Material then?

No, not the same thing. Radar Absorbing Material mean the material can reduce the strength of the radio wave by ABSORBING it. The micro mesh here does not absorb radar wave, it only prevent radar wave from entering the sensor. It has the same purpose as the golden tin on F-22 or F-16 canopy. Yes it can reduce RCS by not allowing the radar wave from entering the cockpit, but it not the same as RAM.

Wavelenght of the N036L PESA/AESA signals is 24cm

Where do you get that number from though? and even 1/2 of 24 is still 12 cm, which is very thick

.There is no doubt that they are real 2D search/detect/track radars.Radars are usually marked with the ''Radiation hazard'' signs.Just like this .

Radiation hazard sign are put on any put on any powerful transmitter, but such transmitter are not necessary be radar
For example:

 

[Squirrel]

This is the simplest way ( copy/paste) to present this some kind of 'Technical Doc.' about the Project 'Scale'. As mentioned before ,this presentation is about decimetric L-band PESA/AESA N036L radars. I've lost my complete tranls of this doc. ,sorry....

2. Цели, задачи и исходные данные для проведения работы

2.1 Цель работы

Разработка технологии, алгоритмов и аппаратных средств оценки и регулировки амплитудно-фазовых характеристик и диаграмм направленности ФАР и АФАР и их элементов в ходе создания и серийного изготовления РЛС.

2.2 Задачи работы

В ходе проведения ОКР должны быть решены следующие задачи:

разработана базовая технология создания линейной ФАР/АФАР Lдиапазона и общая схема ее построения, обеспечивающие реализацию режимов работы ЗГО и радиолокации;

разработаны базовые технологии изготовления ключевых устройств АФАР-L: блока излучателей, приемо-передающего усилительного модуля (ППУМ), устройства распределения и фазирования (УРФ) и формирователя ДН;

разработаны и изготовлены опытные образцы входящих устройств линейной ФАР/АФАР Lдиапазона в соответствии с общей схемой построения;

разработаны программы и методики и проведены настройка и испытания опытных образцов входящих устройств линейной ФАР/АФАР Lдиапазона;

проведены испытания созданной технологии, алгоритмов и аппаратных средств оценки и регулировки амплитудно-фазовых характеристик и диаграмм направленности ФАР и АФАР и их элементов.

разработан комплект КД литеры «О» на опытные образцы входящих устройств ФАР/АФАР Lдиапазона и ТД на разработанные технологии;

получено заключение предприятия-потребителя по уровню параметров, обеспечиваемых разработанной технологией;

даны предложения по предприятию-изготовителю, порядку и срокам освоения изделия.

​

2.3 Исходные данные

В результате выполнения ОКР должны быть созданы базовые технологии для производства ключевых входящих устройств ФАР/АФАР L-диапазона, с учетом возможности размещения на объекте Т-50, в составе:

- блок излучателей должен быть выполнен на излучателях устойчивых к механическим и климатическим воздействиям и обеспечивать заданные характеристики излучения при работе со специализированным радиопрозрачным обтекателем;​

- устройство распределения и фазирования должно быть выполнено на основе ГИС СВЧ с навесным монтажом НЧ управляющих компонентов и

применением микрополосковой линии передачи;

- формирователь ДН должен быть выполнен на основе симметричной полосковой линии, с применением современных материалов типа Rodgers;

- ППУМ должен быть выполнен четырехканальным, с усилителями мощности (УМ) на передачу и на прием в каждом из них. Все УМ выполняются на основе МИС СВЧ с реализацией режимов низкой скважности (Q=20), обеспечиваемых при использовании жидкостного охлаждения. Электрическая схема ППУМ должна обеспечивать сопряжение с магистралью управляющих и информационных сигналов.

В результате выполнения работы заказчику должны быть предъявлены:

1. Комплекты КД литеры «О» на опытные образцы входящих устройств ФАР/АФАР L-диапазона и ТД литеры «О» на разработанные технологии.

2. Макеты входящих устройств ФАР/АФАР L-диапазона.

3. Опытные образцы входящих устройств ФАР/АФАР L-диапазона в составе:

- блок излучателей;

- приемо-передающий усилительный модуль (ППУМ);

- устройство распределения и фазирования (УРФ)

- формирователь ДН.

4. Программа и методика, акты и протоколы испытаний.

5. Ведомости соответствия опытных образцов входящих устройств ФАР/АФАР L-диапазона требованиям ТЗ.

6. Справка о разработанном нестандартном технологическом оборудовании, оснастке, средствах испытаний и измерений, подписанная главным конструктором ОКР.

7. Протокол прогнозирования характеристик ФАР/АФАР L-диапазона по результатам испытаний опытных образцов входящих устройств.

8. Справка о созданных объектах интеллектуальной собственности.

9. Отчет о патентных исследованиях.

10. Заключение предприятия-потребителя по уровню параметров и применяемости разработанного изделия.

11. Предложение по предприятию-изготовителю, порядку и срокам освоения изделия.

12. Научно-технический отчет по ОКР.

13. Технология, алгоритмы и аппаратные средства оценки и регулировки амплитудно-фазовых характеристик и диаграмм направленности ФАР и АФАР и их элементов в ходе создания и серийного изготовления РЛС.

Вся отчетная документация предоставляется Заказчику в отпечатанном виде, а также в электронном виде.

Участник размещения заказа может включить дополнительные предложения о разработке проектов нормативно-технических, методических и технологических документов, необходимых для достижения цели ОКР, для подтверждения и проверки выбранных конструктивно-схемных, конструктивно-технологических и технических решений дополнительно выполнить комплекс экспериментальных работ (макетирование, моделирование, испытания). Такие предложения будут использованы при оценке качества работы в соответствии с порядком, указанным в пункте 22 раздела II «Информационная карта конкурса».

4. Основные требования к выполнению разработки

4.1 Технические требования к создаваемым технологиям

Технология оценки и регулировки амплитудно-фазовых характеристик и диаграмм направленности ФАР и АФАР и их элементов в ходе создания и серийного изготовления РЛС создается в обеспечение соответствия отечественных АФАР современному мировому уровню.

Для подтверждения технологии осуществляется разработка и изготовление опытных образцов входящих устройств ФАР/АФАР L-диапазона и проведение их испытаний.

4.1.1 Разрабатываемые опытные образцы в составе:

- блок излучателей;

- приемо-передающий усилительный модуль (ППУМ);

- устройство распределения и фазирования (УРФ)

- формирователь ДН.

4.2 Требования назначения

4.2.1 ФАР/АФАР L диапазона в составе разрабатываемых опытных образцов входящих устройств предназначена для направленной передачи радиолокационных сигналов и сигналов системы государственного опознавания в диапазоне частот 1.28¸1.44ГГц (поддиапазон ∆f1) и 1.44¸1.55 Ггц (поддиапазон ∆f2) соответственно, а также для приема сигналов в полосе частот 1.28¸1.55 ГГц.

4.2.1.1 Линейная ФАР/АФАР L диапазона в составе разрабатываемых опытных образцов входящих устройств должна обеспечивать одномерное электронное управление лучом во всех заданных диапазонах частот в азимутальном угловом секторе.

4.2.1.2 ФАР/АФАР L диапазона должна формировать следующие ДН.

4.2.1.2.1 При работе в поддиапазоне ∆f1:

- суммарную ДН при работе на передачу и прием;

- разностную ДН при работе на прием (одновременно с суммарной);

- компенсационную ДН при работе на прием (одновременно с суммарной);

4.2.1.2.2 При работе в поддиапазоне ∆f2:

- суммарную ДН при работе на передачу и прием;

- компенсационную ДН при работе на передачу;

- компенсационную ДН при работе на прием (одновременно с суммарной);

4.2.1.2.3 При работе на передачу должна быть предусмотрена возможность формирования суммарной ДН для двух режимов работы — режима максимальной мощности и оптимальной ДН.

4.2.1.2.4 В ФАР/АФАР L диапазона должна быть предусмотрена возможность инверсии ДН – формирования на суммарном входе разностной ДН, а на разностном – суммарной ДН.

4.2.1.3 Сектор электронного сканирования ФАР/АФАР L диапазона в азимутальной плоскости ±55°. Не допускается появление дифракционных лепестков при сканировании в заданном секторе.

4.2.1.4 Поляризация поля излучаемых и принимаемых сигналов — вертикальная.

4.2.1.5 Потенциал при работе на передачу в режиме максимальной мощности должен составлять не менее 360´N2 Вт , где N – число излучателей.

4.2.1.6 Потенциал при работе на передачу в режиме оптимальной ДН должен составлять не менее 250´N2 Вт , где N – число излучателей.

4.2.1.7 Коэффициент усиления в режиме приема должен составлять не менее 7´N2 , где N – число излучателей.

4.2.1.8 Ширина ДН в азимутальной плоскости по уровню минус 3 дБ при работе в поддиапазоне ∆f1 должна составлять.

4.2.1.8.1 При работе на передачу:

- режим максимальной мощности, град - (130±3)/N/cosΘ;

- режим оптимальной ДН, град - (125±3)/N/cosΘ

где Θ – угол отклонения главного максимума ДН относительно нормали к антенне, N – число излучателей.

4.2.1.8.2 При работе на прием, град: (135±3)/N/cosΘ, где Θ – угол отклонения главного максимума ДН относительно нормали к антенне, N – число излучателей.

4.2.1.9 Ширина ДН в азимутальной плоскости по уровню минус 3 дБ при работе в поддиапазоне ∆f2 должна составлять.

4.2.1.9.1 При работе на передачу:

- режим максимальной мощности, град - (102±2)/N/cosΘ;

- режим оптимальной ДН, град - (108±2)/N/cosΘ;

где Θ – угол отклонения главного максимума ДН относительно нормали к антенне, N – число излучателей.

4.2.1.9.2 При работе на прием, град: (120±2)/N/cosΘ, где Θ – угол отклонения главного максимума ДН относительно нормали к антенне, N – число излучателей.

4.2.1.10 Ширина ДН в угломестной плоскости по уровню минус 3 дБ должна составлять 70¸900 град. во всех режимах.

4.2.1.11 При работе в диапазоне ∆f1 максимальный боковой лепесток суммарной ДН должен находиться в зоне ±30°/ cosΘ относительно оси луча. Уровень максимального бокового лепестка при осевом положении луча должен быть не выше минус 17 дБ в режиме передачи и минус 22 дБ в режиме приема.

4.2.1.12 Коэффициент перекрытия боковых лепестков суммарной ДН разностной ДН при работе на передачу в поддиапазоне ∆f2 должен составлять не менее:

Для режима максимальной дальности:

- в секторе сканирования до ±30° - 0.68;

- в секторе сканирования свыше ±25° - 0.62;

Для режима оптимальной ДН:

- в секторе сканирования до ±25° - 0.78;

- в секторе сканирования свыше ±25° - 0.70.

4.2.1.13 Коэффициент перекрытия боковых лепестков суммарной ДН разностной ДН при работе на прием в поддиапазоне ∆f2 должен составлять не менее:

- в секторе сканирования до ±25° - 0.86;

- в секторе сканирования свыше ±25° - 0.80

4.2.1.14 Глубина минимума разностной ДН относительно максимума суммарной ДН должна составлять не менее 25 дБ.

4.2.1.15 Крутизна синтезируемой пеленгационной характеристики (ПХ) должна быть не менее 15cosΘ%/град.

4.2.1.16 Погрешность установки луча не более:

- при работе в поддиапазоне ∆f1: 0.8°/ cosΘ;

- при работе в поддиапазоне ∆f2: 0.6°/ cosΘ.

4.2.1.17 Время установки луча ФАР/АФАР L диапазона в любое угловое положение не должно превышать 10 мкс.

4.2.1.18 Время инверсии ДН не должно превышать 0.4 мкс. Возврат к исходным ДН должен производиться не более чем через 0.4 мкс после подачи управляющего сигнала.

4.2.2 Требования к характеристикам блока излучателей.

4.2.2.1 Уровень КСВН на входе излучателей не должен превышать 1.8.

4.2.2.2 Излучатели должны обладать линейной поляризацией, ортогональной плоскости АФАР.

4.2.2.3 Масса блока излучателей не должна превышать 0,87 кг.

4.2.3 Требования к характеристикам ППУМ.

4.2.3.1 ППУМ должен иметь 4/5 передающих/приемных каналов.

4.2.3.2 Выходная импульсная мощность на один канал должна составлять не менее 400 Вт.

4.2.3.3 Максимальное отклонение значения выходной мощности должно составлять не более 50 Вт.

4.2.3.4 Параметры усиливаемого импульса:

- длительность, мкс - 1¸100;

- скважность - 20¸200;

4.2.3.5 Требования к форме выходного импульса в поддиапазоне ∆f1:

- длительность фронта и спада не более, мкс: 0.1

- обужение огибающей относительно входного

импульса не более, мкс: 0.1

- задержка фронта относительно входного

импульса, не более, мкс 0.1

- скос вершины огибающей не более, % 2

4.2.3.6 Требования к форме выходного импульса в поддиапазоне ∆f2:

- длительность переднего фронта не более, мкс: 0.15

- длительность спада не более, мкс: 0.25

4.2.3.7 Коэффициент шума приемного канала не должен превышать 3 дБ.

4.2.3.8 КПД ППУМ должен составлять не менее 20%.

4.2.3.9 Энергопотребление МППУ не должно превышать 500Вт.

4.2.3.10 Масса ППУМ не должна превышать 4,35 кг.

4.2.4 Требования к УРФ.

4.2.4.1 УРФ должно быть четырехканальным.​

4.2.4.2 УРФ должно формировать на выходах постоянное амплитудное

распределение в случае активной ФАР и неравномерное по специальному закону в случае пассивной ФАР.

4.2.4.3 Разрядность фазовращателя не менее 5.

4.2.4.4 СКО установки фазы на выходах УРФ не должна превышать 5°.

4.2.4.5 УРФ должно обладать КПД не менее 60%.

4.2.4.6 Энергопотребление не должно превышать 19 Вт.

4.2.4.7 Масса УРФ не должна превышать 0,42 кг.

4.2.5 Требования к формирователю ДН (сумматору).

4.2.5.1 Уровень КСВН на входах и выходах формирователя ДН не должен превышать 1.3.

4.2.5.2 Коэффициент передачи от входа к выходам формирователя ДН должен составлять 3.2±0.3 дБ.

4.2.5.3 Развязка между выходами формирователя ДН должна составлять не менее 27 дБ.

4.2.5.4 Масса формирователя ДН не должна превышать 0,13 кг.



4.3 Требования радиоэлектронной защиты

4.3.1 Порядок обеспечения электромагнитной совместимости должен соответствовать ГОСТ В 25 838-83.

4.3.2 Относительные уровни побочных излучений образцы входящих устройств ФАР/АФАР L диапазона, частотная избирательность ППУМ должны соответствовать требованиям ГОСТ РВ 52226-2004 и ГОСТ В 24911-81 с учетом требований п. 4.2.1 и 4.2.3.

4.3.3 Опытные образцы входящих устройств ФАР/АФАР L диапазона по уровням создаваемых электромагнитных помех и восприимчивости к ним должны соответствовать требованиям ГОСТ В 25 803-91.

4.4 Требования живучести и стойкости к внешним воздействиям.

4.4.1 Опытные образцы входящих устройств ФАР/АФАР L диапазона должны быть выполнены во всеклиматическом исполнении (В) по ГОСТ 15 150-69 и быть стойкими, прочными, и устойчивыми к внешним воздействиям в соответствии с ГОСТ РВ 20.39.304-98 группа исполнения – 3.3.1…3.3.5.

4.4.2 В опытных образцах входящих устройств ФАР/АФАР L диапазона рекомендуется не допускать в диапазоне частот до 40 Гц наличие механического резонанса конструктивных элементов узлов.

4.4.3 Повышенная температура среды для опытных образцов входящих устройств ФАР/АФАР L диапазона, размещаемых в передней части отклоняемого носка крыла:

- рабочая, °С – плюс 75°;

- рабочая повышенная кратковременная, °С – плюс 135°;

- предельная, °С – плюс 140°.

4.5 Требования надёжности.

4.5.1 Критерии отказов опытных образцов входящих устройств ФАР/АФАР L диапазона должны быть определены на этапе разработки РКД.​

4.5.2 Значения показателей надежности должны быть подтверждены

расчетным методом на этапе создания РКД.

4.6 Требования эргономики и технической эстетики.

4.6.1 Требования по эргономике и технической эстетике не предъявляются.

4.7 Требования к эксплуатации, удобству технического обслуживания, ремонту и хранению.

4.7.1 По условиям эксплуатации опытные образцы входящих устройств ФАР/АФАР L диапазона должны быть отнесены к аппаратуре группы 3.3.1 ГОСТ РВ 20.39.304-98.

4.7.2 Характеристики и показатели ремонтопригодности должны соответствовать требованиям ГОСТ 21623-76, ГОСТ 18675-79 и ГОСТ 27003-83.

4.7.3 Условия хранения должны соответствовать требованиям ГОСТ В 9.003-80 для неотапливаемых помещений.

4.8 Требования транспортабельности

4.8.1 Опытные образцы входящих устройств ФАР/АФАР L диапазона должны сохранять свою целостность и работоспособность после транспортировки в заводской упаковке автомобильным, железнодорожным, водным и воздушным (на высоте до 11000м) видами транспорта в соответствии с требованиями ГОСТ В 9.001-72.

4.8.2 Условия транспортирования – «жесткие». Упаковочная тара и способы крепления должны соответствовать группе «ж» ГОСТ В 9.001-72.

Примечание - Инструкция по транспортированию не разрабатывается.

4.9 Требования безопасности.

4.9.1 Конструкция и схемотехническое решение опытных образцов входящих устройств ФАР/АФАР L диапазона должна обеспечивать безопасность личного состава от опасных напряжений в процессе функционирования и при техническом обслуживании аппаратуры, а также исключить возможность попадания электрического напряжения на наружные металлические части, в том числе ручки и рукоятки органов управления.

По безопасности образцы должны соответствовать требованиям ГОСТ РВ 20.39.309-98 раздел 18 и ОТТ ВВС-86 книга 4, раздел 2.3.

4.9.2 Опытные образцы входящих устройств ФАР/АФАР L диапазона должны быть спроектированы так, чтобы была исключена возможность возгорания, появления дыма, запаха или ядовитых газов, как при штатной работе, так и при возможных отказах или неисправностях.

4.9.3 Конструктивно-технические особенности опытных образцов входящих устройств ФАР/АФАР L диапазона не должны оказывать вредного влияния на окружающую среду при эксплуатации, техническом обслуживании и ремонте.

4.9.4 Уровни высокочастотного излучения, создаваемого опытными образцами входящих устройств ФАР/АФАР L диапазона должны соответствовать требованиям ГОСТ В 21953-76.​

4.9.5 Уровни излучения СВЧ энергии опытных образцов входящих устройств ФАР/АФАР L диапазона при проведении технического

обслуживания и ремонтно-восстановительных работ не должны превышать санитарных норм.

Должна быть обеспечена экологическая защита обслуживающего наземного персонала от облучения.

4.10. Требования обеспечения режима секретности

4.10.1 Мероприятия по обеспечению режима секретности, перечни охраняемых параметров определяются Главным конструктором ОКР на этапе РКД.

4.11. Требования защиты от ИТР

4.11.1 Мероприятия по защите от ИТР, перечни охраняемых параметров определяются Главным конструктором ОКР на этапе РКД.​

 

[flateric]

Take a look on the Luneberg lenses under the Su-57's wing...

View attachment 761732

You mean these cameras?

 

[Airborne2001]

With the current discussion about RAM and what not, I think it is time to bring up this Quora post about the Su-57 I found:

Answer to What is the RCS of the SU 57? by Jack https://www.quora.com/What-is-the-R...&share=7deed743&srid=RCYM3&target_type=answer

It is long, but there are a lot of pictures haha! Essentially, the RCS isn't as good as the F-35 and F-22, but it is much better than people say.

 

[Joint Soviet Fighter]

With the current discussion about RAM and what not, I think it is time to bring up this Quora post about the Su-57 I found:

Answer to What is the RCS of the SU 57? by Jack https://www.quora.com/What-is-the-R...&share=7deed743&srid=RCYM3&target_type=answer

It is long, but there are a lot of pictures haha! Essentially, the RCS isn't as good as the F-35 and F-22, but it is much better than people say.

Most, if not all, of those pictures are of various simulations that stealthflanker has posted on here over the years, just in case you didn't know .

As for the rcs, under the best possible scenario, The Su-57 would appear to be roughly on the level of The J-20, hence as to why many have pointed out the problems with using an irst bulb, the fact that the space between the engines creates a tunnel instead of the underside being smooth like every other stealth fighter, & don't discount the penalties that result from the dircms, either, as it all adds up.

Details matter.

 

[Airborne2001]

Most, if not all, of those pictures are of various simulations that stealthflanker has posted on here over the years, just in case you didn't know .

As for the rcs, under the best possible scenario, The Su-57 would appear to be roughly on the level of The J-20, hence as to why many have pointed out the problems with using an irst bulb, the fact that the space between the engines creates a tunnel instead of the underside being smooth like every other stealth fighter, & don't discount the penalties that result from the dircms, either, as it all adds up.

Details matter.

Yeah, after looking more into it the IRST bulb is definitely not the best for a stealth aircraft, and in fact now I think the figures Jack came to in his quora answer would be more likely with the bulb not being present (among the other things you mentioned). I wonder how the Su-57M could improve upon this if it can. I think the new flat nozzles that have been tested recently could be a huge help.

 

[Joint Soviet Fighter]

Yeah, after looking more into it the IRST bulb is definitely not the best for a stealth aircraft, and in fact now I think the figures Jack came to in his quora answer would be more likely with the bulb not being present (among the other things you mentioned). I wonder how the Su-57M could improve upon this if it can. I think the new flat nozzles that have been tested recently could be a huge help.

It's especially odd when you consider that The Soviet Union fielded this irst on The MiG-23 -

https://www.secretprojects.co.uk/threads/mig-23s-tp-23-and-tp-26-irst.22169/

Overall, I really don't think that the issue is technological as opposed to having the wrong requirements for The Su-57 that ultimately compromise its rcs as is the case with the two weapons bays, with the result being a lack of S-Ducts & too much weight on the airframe, after which they increased the overall structural strength & opted for "partial S-Ducts" with a radar blocker, that, sure, is better than nothing, but is still not quite on par with the intake arrangement from an rcs perspective on almost all of the other stealth planes, so the bottom line is that you wind up with a missile truck that deprives you of achieving the optimal rcs. I mean, you don't have to be a genius to figure out that carrying more missiles than your opponent doesn't mean much when they can detect you at greater range than you can locate their fighters. This isn't even an East vs. West thing, either, btw - it's just common sense, especially when you factor in that Russia only ordered 76 Su-57s, so if you don't have the numbers against an alliance with a thousand F-35s, etc., I would think that it would be obviously incumbent upon your design team(s) to produce an aircraft with the best possible rcs, otherwise what are we doing, here?

Perhaps think of it this way - would you rather pay, idk, 40K for a Lancet that has only destroyed something like 30% of its targets owing to having a 5 kg warhead, or would you prefer to purchase, say, a laser-guided Grad rocket/glide bomb that has 3-5x the firepower for maybe half as much?

Personally, as someone who is used to working with less, this entire setup makes absolutely no sense (doctrinal differences be damned).

 

[Airborne2001]

It's especially odd when you consider that The Soviet Union fielded this irst on The MiG-23 -

https://www.secretprojects.co.uk/threads/mig-23s-tp-23-and-tp-26-irst.22169/

Overall, I really don't think that the issue is technological as opposed to having the wrong requirements for The Su-57 that ultimately compromise its rcs as is the case with the two weapons bays, with the result being a lack of S-Ducts & too much weight on the airframe, after which they increased the overall structural strength & opted for "partial S-Ducts" with a radar blocker, that, sure, is better than nothing, but is still not quite on par with the intake arrangement from an rcs perspective on almost all of the other stealth planes, so the bottom line is that you wind up with a missile truck that deprives you of achieving the optimal rcs. I mean, you don't have to be a genius to figure out that carrying more missiles than your opponent doesn't mean much when they can detect you at greater range than you can locate their fighters. This isn't even an East vs. West thing, either, btw - it's just common sense, especially when you factor in that Russia only ordered 76 Su-57s, so if you don't have the numbers against an alliance with a thousand F-35s, etc., I would think that it would be obviously incumbent upon your design team(s) to produce an aircraft with the best possible rcs, otherwise what are we doing, here?

Perhaps think of it this way - would you rather pay, idk, 40K for a Lancet that has only destroyed something like 30% of its targets owing to having a 5 kg warhead, or would you prefer to purchase, say, a laser-guided Grad rocket/glide bomb that has 3-5x the firepower for maybe half as much?

Personally, as someone who is used to working with less, this entire setup makes absolutely no sense (doctrinal differences be damned).

Reading this I see where you are coming from. I think, in all honestly, Sukhoi would need to make an "Su-67" to address the changes. Redesign for S-ducts, redesign for a flat underbelly*, etc. The Su-57M will be a decent enough stopgap, but better is needed. Therefore, I think the Su-57 (at least for now) is closer to the open IRST number than the closed one, as mentioned in Jacks Quora answer.

This reinforces my thoughts about people saying that the RuAF might very well be the first buyer of the Su-75. It has a flat underbelly, and the engine is significantly better in terms of being hidden from radar view. Plus, the lower production cost counts.

*By the way, why didn't they take this from this Su-47?

The Su-47 wasn't even a proper stealth plane, yet it had the flat underbelly. I wonder why Sukhoi didn't keep that.

 

[stealthflanker]

Answer to What is the RCS of the SU 57? by Jack https://www.quora.com/What-is-the-R...&share=7deed743&srid=RCYM3&target_type=answer

I am actually expecting something better tho than digging my twitter accounts and my secretproject forum posts, also considering the answerer claim to be physics student, he should be in better position in making his own modeling. My major was Biology back in University.

Also i have moved on from that, with some updates including some speculation on Su-57 skin "stacks"

https://twitter.com/x/status/1726523299113615671

View: https://x.com/Flankerchan/status/1726523299113615671

 

[Joint Soviet Fighter]

Reading this I see where you are coming from. I think, in all honestly, Sukhoi would need to make an "Su-67" to address the changes. Redesign for S-ducts, redesign for a flat underbelly*, etc. The Su-57M will be a decent enough stopgap, but better is needed. Therefore, I think the Su-57 (at least for now) is closer to the open IRST number than the closed one, as mentioned in Jacks Quora answer.

This reinforces my thoughts about people saying that the RuAF might very well be the first buyer of the Su-75. It has a flat underbelly, and the engine is significantly better in terms of being hidden from radar view. Plus, the lower production cost counts.

*By the way, why didn't they take this from this Su-47?
View attachment 761900
The Su-47 wasn't even a proper stealth plane, yet it had the flat underbelly. I wonder why Sukhoi didn't keep that.

I always thought that The Su-47 was so cool, much in the same manner as The YF-23 was radically different to what eventually became The F-22, & unlike The Su-57, The Berkut also had proper S-Ducts but only one weapons bay. I could also see them modifying the design to change the shape of the intakes & add levcons later down the road, but ultimately, one of the primary reasons that it was never adopted was due to the problems with forward-swept wings limiting the maximum speed to Mach 1.6, which, ironically enough, is currently the same limit as The F-35, albeit for reasons related to RAM, iirc.

Never forget, however, that The Su-47 first flew at a time when Russia was still in the abject misery of The 1990s, so the money simply wasn't there, even if it could have been built in numbers, so in the end, the platform wound up being a kind of flying laboratory for various technologies that were later incorporated into The Su-57, so it wasn't a total loss. I can't do anything about the irst bulb, though, lol, smh.

As for The Su-75, yes, it's a much better stealth design, especially if they opt to keep the v-tail, & The Checkmate also features a faceted EOTS-like device underneath the fuselage, so it looks like someone at Sukhoi finally got the memo in that regard, but evidently, everyone is STILL not on the same page as the aircraft retains the standard irst bulb in front of the cockpit. Sigh.

In terms of modifying The Su-57, it would probably be best to get rid of the second weapons bay so as to ease the overall stress on the airframe & then smooth the bottom, which would also yield more storage for the single weapons bay. Do that, give us a faceted irst, said EOT-like setup from The Su-75, & then let's see where we are in terms of its rcs. Who knows - a return of 0.006 m2, or thereabouts, might actually be quite attainable, provided that the dircms are also removed. Continuing down the current road is just a waste of time & money, imo.

Oops, almost forgot - the partial S-Ducts are also complex, expensive, & don't yield the necessary level of radar reduction, so yeah. Not great, Bob.

 

[Squirrel]

You mean these cameras?

Cameras ??? Three ball-like cameras one to the each other, hm. I first saw those 'balls' in one reportage from Russia 1HD TV on May 2018 several days before Victory Parade. Famous reporter Nayla Asker-Zade interviewed Sukhoi test pilot Taras Artsebarsky. I have some sequences from that video but video itself, I could not find.


Btw cameras that were used for monitoring AAM/ASM test launches in 929 GLITs -Akhtubinsk test range are packed in one container.There is three cameras for monitoring test launches from fuselage weapon bays and under fuselage weapon bays,also for monitoring test launches of AAM/ASM launched from underwing pylons.There is rear looking camera for monitoring test launch of AAM that can engage air targets in the rear hemisphere of the Su-57.

 

[Squirrel]

No, not the same thing. Radar Absorbing Material mean the material can reduce the strength of the radio wave by ABSORBING it. The micro mesh here does not absorb radar wave, it only prevent radar wave from entering the sensor. It has the same purpose as the golden tin on F-22 or F-16 canopy. Yes it can reduce RCS by not allowing the radar wave from entering the cockpit, but it not the same as RAM.


Where do you get that number from though? and even 1/2 of 24 is still 12 cm, which is very thick


Radiation hazard sign are put on any put on any powerful transmitter, but such transmitter are not necessary be radar
For example:
View attachment 761853
View attachment 761854

OK, then we can call it 'RPM' ( radar preventing material ), not RAM ,tnx.

About the wavelength , If I remember well ,value was from one interview with gen.dir. of NIIP named after V.V. Tikhomirov Jury Beliy in ''Национальная оборона'' or National Defence.I will try to find it.

About those 'Radiation hazard' signs. Yes, I know that we can see them even on the jamm stations. Modified jam-station L265M10-01M on Su-35S got that signs e.x. For me it is interesting that serial/operational Su-57's haven't that signs on L-band antennas.

https://www.reddit.com/r/WarplanePorn/comments/sjlxy8/a_new_pair_of_serial_production_su57s_no02_and_52

View: https://www.reddit.com/r/WarplanePorn/comments/sjlxy8/a_new_pair_of_serial_production_su57s_no02_and_52/#lightbox


If we talk about only interrogator-IFF L-band antennas ,the main question is ,why they use four antennas for that.We can clearly see difference between interrogator-IFF L-band antenna of Su-35S and those L band PESA/AESA of Su-57.

 

[Ronny]

OK, then we can call it 'RPM' ( radar preventing material ), not RAM ,tnx.

Or you can just call it metal layer/ metal mesh since it is literally just a thin layer metal

If we talk about only interrogator-IFF L-band antennas ,the main question is ,why they use four antennas for that.

Well, maybe so that you can jam and perform IFF fucntion at once?. Or maybe simply so that you can cover both side since Su-57 wing has very big swept angle and ESA aren’t exactly known for high boresight capability

We can clearly see difference between interrogator-IFF L-band antenna of Su-35S and those L band PESA/AESA of Su-57.

They are both electronic scanned array