F-35 vs Su-30/35

The F-35 compared with other modern jets.
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by sergei » 11 Apr 2015, 23:35

on average - 20 dB front 135-45 degrees,-10dB on 90,on 135 and 45 a large peak to 20 dB, then a gradual increase with -10dB to +20dB to 180-0 degrees,after 180-0 decrease from +20dB to -10dB with peak to 10bB at 270 degrees


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by sergei » 12 Apr 2015, 00:30

eloise wrote:
sergei wrote:
You are free to back up this claim, at least indicating the characteristics of the radar of F-35 (the area of antenna, the maximum power)

Irbis-e can detect target with RCS = 0.01 m2 from 90km , so according to radar equation (reduce RCS by factor of 10 cuts the notional detection range by 44 percent ) it can detect target with RCS = 0.001 m2 from 50.4 km , tracking range is around 80% of detection range ,since F-35 have RCS = 0.0015 m2 , irbs-e can track the F-35 from 40 km ( in perfect condition , no jamming , no clutter ...etc)
Apg-81 can track target with RCS =1 m2 from 150 km ,Su-35 have RCS = 10 m2 so according to radar equation , Apg-81 can track Su-35 from around 275 km ( in perfect condition )
However both side will likely use jamming : F-35 gonna use ALE-70 , APG-81 , MALD-J , Su-35 gonna use KNIRTI SAP 518 ..etc so the number above will be reduced significantly ,may be only to half as big ( Su-35 many only able to trackF-35 at 20 km )

since F-35 have lower radar cross section it will have this advantage as well :
Image
not only that lower RCS reduce burn through distance , jamming power required will decrease in the same rate as RCS reduction ,50% reduction in RCS = 50% less power required to overwhelm real radar reflection with noise ( you can work it out for yourself , 99.9% reduction in RCS= 99.9% less power required to achieve same level of effectiveness , and so on )
now let take example of 4 aircraft :
1) B-52 : RCS = 100 m2
2) Su-35 : RCS = 10 m2
3) F-16 : RCS = 1 m2
4) F-35 : RCS = 0.001 m2
now compared them :
from B-52 to F-35 then RCS is reduced by 99.999% =>99.999% less power require
from Su-35 to F-35 then RCS is reduced by 99.99%=>99.99% less power require
from F-16 to F-35 then RCS is reduced by 99.9% =>99.9% less power require
so despite the fact that su-35 is much bigger , and can carry jammer that is more powerful than the F-35's one , Su-35 jamming is still gonna be less effective ( assume both side have equal technology level )




sergei wrote:35km/90km-this data is from 2013 , in 2010-2011 it was 25km/50km, in 2007 it was 15km/45km(for mig 29 as target)
http://www.youtube.com/watch?v=XMd7YWrGMNU
0.00-0.27
http://www.knaapo.ru/media/rus/about/pr ... et_rus.pdf
PAGE 12
50km/90km

so the maximum range that OLS-35 can detect a fighter head on is 50 km
however there are 2 things you should remember
1- that is detection range , to generate firing solution for missiles , IRST rely on LRF , and the LRF on OLS-35 is limited to only 20 km
2- while IRST is not affected by jamming , infrared radiation is absorbed by moisture very significantly so your IRST will be quite useless if the weather is bad or if enemy fighter decide to fly in or near the cloud





sergei wrote:"The F-35 has an RCS TARGET of 0.003-0.001m^2." - I suspect that this is at very specific angles of irradiation.

.

0.001 m2 may sound pretty low , however it have been achieved very long time ago since HAVE BLUE program (aka F-117 program ) , iam pretty sure the F-35 that was designed 20 years later can at least match that
The main emphasis is laid on the radar reflection from the front sector, which has been defined as a region of 45 degrees to each side of the longitudinal axis of the machine. Aircraft had to face the primary Gun Dish radar, which used light armored Soviet radar anti-aircraft gun ZSU-23-4 and worked in the J band at a frequency of 16 GHz. Hopeless Diamond and its derivative Lockheed Have Blue were optimized almost exclusively on the radar and range of frequencies. As the possibility of calculating RCS improve, increased the range of the target frequency, but the main focus was still on the radar gun measures Dish. In contrast, the plane of Northrop were of low radar cross at lower frequencies in the zones A and B which used the long-range radar. However, since a similar design is always compromises, the price for a wider range of frequencies were slightly worse in the principal target zone A.

Image
http://www.hitechweb.genezis.eu/stealth2.htm
btw it is interesting to note that they achieve low RCS not only again X-band but also again frequency from 2.3 Ghz to 16 Ghz

I got info that Su-35 RSC is 0.5-2 not 10


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by eloise » 12 Apr 2015, 03:54

sergei wrote:I got info that Su-35 RSC is 0.5-2 not 10

well then that info is wrong then, here is Su-35 RCS graph with and without RAM
Image
sergei wrote:on average - 20 dB front 135-45 degrees,-10dB on 90,on 135 and 45 a large peak to 20 dB, then a gradual increase with -10dB to +20dB to 180-0 degrees,after 180-0 decrease from +20dB to -10dB with peak to 10bB at 270 degrees

not sure if you are right or wrong , but just take value from the pictures below, minus another 18 or 30 dBsm depending on frequency then you will have what you want
Image

Btw here is an interesting link that worth looking at too
https://books.google.com.vn/books?id=b5 ... =html_text


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by bring_it_on » 12 Apr 2015, 05:17



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by eloise » 12 Apr 2015, 07:29

bring_it_on wrote:https://www.scribd.com/doc/261603337/Scattering-Characteristics

thanks bring_it_on, that is alot more details and much better resolution


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by ata » 12 Apr 2015, 11:34

Firstly, neither F-22 or F-35 are invisible , they just have really low RCS thus enemy cant detect them soon enough, allow them to have first look, first shot, first kill advantage ( just like a submarine)

Secondly, recently according to general Hostage, F-35 is even more stealthy than F-22 ( it likely that at the start they didn't required f-35 to have better LO characteristics than F-22, however it
is said that F-35 excess the LO requirements)

Thirdly, almost most all fighter radar only have FoV of around 60 degree ahead, and in BVR they are likely to go head on to the other


Oh man...
Ok, let's go step by step. At first, I was using word "invisible" just to avoid always word "stealth". Ok, I wont do this it makes problems of understanding.
have really low RCS


Again and again - where are the numbers? Let's check what you have posted. First is the picture of F-22 simulation:

Last, look at the pictures below ( RCS simulation of stealth fighter like F-22, F-23)
Image


As I said it's 2D (!) simulation of another (!) plane. It's a good picture which can be used as a reference. Also, if we compare it with other similar pictures we can clearly see that metal body has bad RCS from sides, at 45 angle, and from the back.
There is no more information in this picture. I mean no more helpful information. No information we can use in any calculation.
I trust you that general Hostage said that. But even if we assume that "Bachelor of Science degree in mechanical engineering" is enough to understand the whole massive radio tech part of physics, then why do you think he mean different thing than I already said about LM guys? I agree F-35 in some projections could be better that F-22. But what does it mean practically?
It's no matter how wide radar beam is. If I'll come to you from 45 azimuth, even 10 degrees will be enough for me. Or maybe you want to say that fighters always attack from the front?

Let's go ahead:

without RAM the 90 degree frontal arcs have RCS of around - 20 dBsm with some part reached - 13 dBsm, 2 spike reached - 5 dBsm but the angle is too narrow to have significant impact

without RAM the 90 degree tail arc have RCS fluctuating between -5 dBsm and 0 dBsm , and reached the peak of 10 dBsm if the enemy is directly behind

RCS from the side are very high, however when you fly perpendicular to enemy then doppler effect on reflect signal will be really low thus they are rejected by enemy radar, as a result your fighter become invisible

Now we dont know exactly what kind of RAM and paint that F-22 and F-35 use, they are likely using many different kind of advanced RAM at the same time, so we can only estimated
Image
Image
Image

it can be seen from these graph that using different kind of RAM can reduce RCS by another 18-30 dBsm depending on frequently
( now you can put this and the picture above together to estimated F-22/35 RCS from different angle if they have RAM, may be come up with sth like this, yourself

Image


Again, no. If you want more or less meaningful analysis this way is wrong.
Every RAM only realise it's best when it's used specifically. If you use one after another or mix of them you'll get less performance for every of them.
Moreover, it's not a big deal to make flat shape to be "stealthy". The biggest deal is to make the same for things like cockpit (btw, F-22 has one piece of "glass" version, while F-35 has a frame, which is also radio-reflecting element) - it's simply hard to paint a pilot with RAM as well. What about radar? You can't protect radar with RAM. There are ways to reduce it's impact, but you can't terminate it anyway. Optical elements, the same problem, do you know if any RAM can be transparent? And because X-band wavelength is about 3cm, then all the elements including any curves, any edges with comparable or bigger size will be a problem.
Radar, pilot, everything inside cabin, inside optical elements - all of those you can't apply to your "metal body simulation" + "RAM graph".
I'm absolutely sure that LM guys know that much-much better than me, and they of course know how to deal with that, but it's simply impossible to completely remove all those things.
I believe, this is a reason, why F-22 is not equipped with EOTS/DAS sensors, for example.
Again and again, another problem - engines. You can't use effective RAM inside of engine nozzle. It means every time I can see part of it - I see it clearly. And of course turbine blades (which are visible from quite a wide angle from the rear) are very radar-bright as well.


by your way of thinking then any information related to Su-30/35 come from sukhoi as well so what is your point?
btw the theory about how stealth affected jamming and radar range doesn't come from LM, the radar equation doesnt come from LM , the simulation of RCS and RAM that i posted above doesn't come from LM either, even the theory of how LPI doesn't come from LM. they are not even advertising but rather the principles based on physics


What are the tactical advantages of Su-35? Speed. Range. Radar. Manoeuvrability. Armament. Do you have any question about any of those points? Do you need explanation how every of them could help in a fight? We can discuss.
What the tactical advantages of F-35? Stealth. Radar. Optical sensors. And it's clear already there are plenty of question on every of them.

No things are not that simple
again you dont understand how a RWR classified the signal as threat, just because it can detect something doesnt mean it can classified that thing as enemy radar, if RWR instantly classified anything it detect as enemy radar then your screen will be filled with background noise, ground reflection from your own radar, datalink or ECM : ( read the slide below about compression of pulse)
Image


I've read that article. And some others as well. LPI is not a magic (as well as stealth) and concept is very clear. Bu again, please read this carefully: "to be detectable for it's own radar level of reflected signal must be at least comparable with noise level. In the meantime power of LPI signal received at target side will be THOUSANDS time higher than reflected back to F-35" - there is only one way how to avoid it. Receivers at F-35 side must the same time more sensitive. In fact thousands times more sensitive. And not simply "more sensitive" but with thousands times higher selecting ability. If they're not, then signal level received at target side will be always higher, and will be detectable easily. And then it's only a question of target radar if it's able to detect it. And I was surprised, but seems like S-300/400 missiles also has this option. So, it's pretty well know technology.
I think idea of LPI was exactly how it's described in wiki: "A low-probability-of-intercept radar (LPIR) is designed to be difficult to detect by passive radar detection equipment (such as a radar warning receiver – RWR) while it is searching for a target or engaged in target tracking." In this case LPI could really help, making F-35 to be detectable not just from horizon, but from maybe 100-200 km. Which makes sense, of course.


i have explained this before
Firstly, it very very unlikely that your RWR recognised APG-81 signal as radar signal


Again, it's only a question of distance and processing (because LPI switches frequency), but it's not a big deal anyway.

Secondly, even if it does, and you managed to track the F-35 by your RWR , you still cant attack it by missiles because you cant use RWR to measure range or speed of a moving air target, the only thing you know is the direction
there are 6 ways a RWR can geolocate a ground radar for an aircraft to attack it
Image
owever none will work again air target using AESA radar
here is why :
1- triangulation method required target to be stationary , and take very long time
2- Azimuth / Elevation method will not work because you dont know enemy fighter altitude ( for a ground target you know the altitude is 0 ) thus cant use the Sine and Cosine function to work out the distance to target
3 - Time different arrival method required at least 3 aircraft stay at significant distance from the other ,but doesnt work again AESA radar due to it very small side lobe , and thin beam

there are some additional methods to determine distance by RWR included :
4- phase rate change : doesnt work again air target because it required target to be stationary to be accurate
5- determine distance by signal strength : required to threat radar characteristic to be known , and still doesnt work because F-35 can reduce radar transmitting power at short range to reduce probably of detection
6- RF doppler processing : doesnt work again air target because both side are moving ,and you dont know the moving speed of enemy


No difference. LPI is still source of signal. All of this also works for F-35 receiving signal from Flanker radar. You can only make any conclusion if you detect the target with your own radar.
There is also a "detection probability" because even if your beam is 2 degrees thin, at 100 km range it will be 3,5 km spot and because beam's gain is not constant than Flanker must be in the center or close to the center of that spot (3,5 km diameter). If it's not in the center then there is a probability that F-35 will not detect it. BUT, because as I said signal in incoming beam is thousands time higher than in reflected Flanker will detect F-35 even at the edge of that spot.
Let's also talk about plane coming from the side. Why do you think it's invisible? How do you think doppler radar works? First of all, of course that plane will be moving for me, because I'm moving to it! The only problem here is that I can't recognise it for example from the mountain behind it. But that's why modern radars are using impulse+doppler technique. Moreover after two scans I'll be able even make a conclusion about it's speed, because it will move in front of me.

no, I gave you many number, as well as theory on how things work, most of them not even from LM, but you just dont bother to read any of that
for example the RCS have been discussing many time, and you got the info from both USAF, LM, as well as simulation of the third party , but you just really un willing to accept it


It works like this: you give me a number which is simulated and can't be used in any conclusion and you build your theory on those numbers. But if I give you another number (for example about engines visibility) you say no, it's wrong, let's see our simulation. So, from your numbers there is no one we can take as a basis. NO ONE.


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by sergei » 12 Apr 2015, 11:49

eloise wrote:
sergei wrote:I got info that Su-35 RSC is 0.5-2 not 10

well then that info is wrong then, here is Su-35 RCS graph with and without RAM
Image
sergei wrote:on average - 20 dB front 135-45 degrees,-10dB on 90,on 135 and 45 a large peak to 20 dB, then a gradual increase with -10dB to +20dB to 180-0 degrees,after 180-0 decrease from +20dB to -10dB with peak to 10bB at 270 degrees

not sure if you are right or wrong , but just take value from the pictures below, minus another 18 or 30 dBsm depending on frequency then you will have what you want
Image

Btw here is an interesting link that worth looking at too
https://books.google.com.vn/books?id=b5 ... =html_text

I said Su-35 RSC = 0.5-2 with ram, you dont have Su-35 diagram you got Su-27 without ram.


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by eloise » 12 Apr 2015, 12:56

sergei wrote:I said Su-35 RSC = 0.5-2 with ram, you dont have Su-35 diagram you got Su-27 without ram.

what exactly do you think are different between a Su-27 and Su-35? apart from engine, Radar and internal EW equipment ?
they basically have similar shape, made from similar material
also in the graph i posted, the one on the left is Su-27 RCs without RAM, the one on the right is Su-27 with RAM painted on engine fan blade, Missile, pylon, and have a plasma screen in front of its radar


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by sergei » 12 Apr 2015, 16:47

eloise wrote:
sergei wrote:I said Su-35 RSC = 0.5-2 with ram, you dont have Su-35 diagram you got Su-27 without ram.

what exactly do you think are different between a Su-27 and Su-35? apart from engine, Radar and internal EW equipment ?
they basically have similar shape, made from similar material
also in the graph i posted, the one on the left is Su-27 RCs without RAM, the one on the right is Su-27 with RAM painted on engine fan blade, Missile, pylon, and have a plasma screen in front of its radar


Su-27 + ram
http://vivovoco.astronet.ru/VV/JOURNAL/ ... STELLS.HTM]

Su-35
http://www.knaapo.ru/products/su-35/

Основными особенностями самолета Су-35 являются: ____Конструктивные мероприятия по снижению радиолокационной заметности._____


The main features of the Su-35 are: _________ Structural measures to reduce the radar signature._______


RAM is not "Structural" it coating.


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by eloise » 12 Apr 2015, 17:48

sergei wrote:
Su-27 + ram
http://vivovoco.astronet.ru/VV/JOURNAL/ ... STELLS.HTM]

Su-35
http://www.knaapo.ru/products/su-35/

Основными особенностями самолета Су-35 являются: ____Конструктивные мероприятия по снижению радиолокационной заметности._____


The main features of the Su-35 are: _________ Structural measures to reduce the radar signature._______


RAM is not "Structural" it coating.

1- the exterior airframe of su-27 and su-35 is exactly the same,they made from same material, i cant find any source mention anything different, left alone significant difference ( by contrast you can find many sources state many difference between F-18C and F-18E/F airframe for example)
2- Su-27 with RCS reduction measures are actually just a study, as far as i know there isn't any Su-27 in production with RAM painted on the engine fan blade and a plasma screen in front of it's radar

so in my opinion the Su-35 have RCS of 10 m2 that is after radar absorbing paint have been painted on the engine fan blade and pylon ( i guess you can reduced Su-35 RCS significantly if you can have sth to block the view of engine fan blade, like DSI, but they dont have anything like that on Su-35)
btw according to this link the aircraft in the study was a Su-35 http://www.fighter-planes.com/stealth2.htm
Last edited by eloise on 12 Apr 2015, 20:01, edited 1 time in total.


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by eloise » 12 Apr 2015, 19:15

ata wrote:Oh man...
Ok, let's go step by step. At first, I was using word "invisible" just to avoid always word "stealth". Ok, I wont do this it makes problems of understanding.

i dont like using the word invisible because, nothing is invisible, that word will cause misunderstanding because many radar producer claim that their radar can detect stealth aircraft , which is a really meaning less claim, because any radar can do that, the only problem is distance



ata wrote:Again and again - where are the numbers? Let's check what you have posted. First is the picture of F-22 simulation:
As I said it's 2D (!) simulation of another (!) plane. It's a good picture which can be used as a reference. Also, if we compare it with other similar pictures we can clearly see that metal body has bad RCS from sides, at 45 angle, and from the back.There is no more information in this picture. I mean no more helpful information. No information we can use in any calculation.

1) i gave you the USAF claim for F-35 RCS, which is around 0.0015 m2

2) when you complain that F-35 will only have low RCS from very narrow frontal angle, i gave you F-117 average frontal RCS that they measured in Have Blue program, which is around 0.001 m2 within 45 degree frontal

3) i also gave you the simulation of YF-23 radar scattering characteristics without RAM, sure it a bigger aircraft than f-35 but they are both stealth fighter with somewhat similar shape, btw in the pictures RCS was measured in dBsm
so i dont really understand what you mean by not enough number?

if you can some how get a perfect 3D model of F-35, put it in the software to calculate radar scattering characteristics, and the results from that are somehow different from mine then go a head, do that and post it here , iam always open to learn new things
ata wrote:I trust you that general Hostage said that. But even if we assume that "Bachelor of Science degree in mechanical engineering" is enough to understand the whole massive radio tech part of physics, then why do you think he mean different thing than I already said about LM guys? I agree F-35 in some projections could be better that F-22. But what does it mean practically?

i dont really get what you trying to say, obviously stealth aircraft are more stealthy from some angle than the other, because they doesn't have round shape

ata wrote:It's no matter how wide radar beam is. If I'll come to you from 45 azimuth, even 10 degrees will be enough for me. Or maybe you want to say that fighters always attack from the front?

i dont quite understand what you trying to say, can you draw a picture or something ? , if you are trying to say you will spread su-35 formation apart so that they will see F-35 from angle wider than 45 degree each side and F-35 can't turn it's nose to them, then the Su-35 must be very very far apart from each other , for example if the distance between f-35 and su-35 is 100 km then to be able to see F-35 from angle of 45 degree then the su-35 must be about 200 km from the other
http://www.cleavebooks.co.uk/scol/calrtri.htm

ata wrote:Again, no. If you want more or less meaningful analysis this way is wrong.
Every RAM only realise it's best when it's used specifically. If you use one after another or mix of them you'll get less performance for every of them.

do you have any source that support that statement ? , also i didnt mean to plus all their absorbing capabilities together like at 10 Ghz type A absorb 20 dbsm + type B absorb 10 dBsm = 30 dBsm, what i mean is combine them, some RAM work well at low frequency but bad at high frequency , some good at high frequency but bad at low frequency .. and so on
also : F-35 doesn't have just RAM and shaping, it has RAS as well

Major Vassilios A. Evangelidis, Hellenic Army Aviation, wrote:
[...] On the F-35 several special materials are used, including Radar Absorbing Materials (RAM), Radar Absorbing Structure and Infrared (IR) Topcoat. Unlike the F-117, which was totally coated with 2,000 pounds of RAM, these materials are more selectively used on the JSF. Lockheed Martin developed paint-type RAM which is applied around the edges of doors and control surfaces. RAS is used on the body, wing and tail edges. For the application of this paint robots will be used, like the CASPER (Computer Aided Spray Paint Expelling Robot) system used for F-22 and the Have Glass II program used for painting 1,700 F-16s with RAM. Robots are essential because they can reach confined areas, as the inlet ducts, and can work without stepping on the aircraft.

These materials comprise ferromagnetic particles, embedded in a high-dielectric-constant polymer base. The dielectric material slows down the wave and the ferromagnetic particles absorb the energy. These coatings are also designed in a way that the small reflection from the front face of the absorber is cancelled by a residual reflection from the structure beneath it. This is not an easy procedure, and it makes RAM design much more tricky than most people believe.

JSF’s entire airframe is also painted with a camouflage topcoat that suppresses IR.



ata wrote:Moreover, it's not a big deal to make flat shape to be "stealthy". The biggest deal is to make the same for things like cockpit (btw, F-22 has one piece of "glass" version, while F-35 has a frame, which is also radio-reflecting element) - it's simply hard to paint a pilot with RAM as well. What about radar? You can't protect radar with RAM. There are ways to reduce it's impact, but you can't terminate it anyway. Optical elements, the same problem, do you know if any RAM can be transparent? And because X-band wavelength is about 3cm, then all the elements including any curves, any edges with comparable or bigger size will be a problem.
Radar, pilot, everything inside cabin, inside optical elements - all of those you can't apply to your "metal body simulation" + "RAM graph".
I'm absolutely sure that LM guys know that much-much better than me, and they of course know how to deal with that, but it's simply impossible to completely remove all those things.
I believe, this is a reason, why F-22 is not equipped with EOTS/DAS sensors, for example.

look at F-22 and F-35 canopy, they are not completely transparent are they? , that is because they are coated with really thin layer of gold to prevent the radar wave from entering the cockpit, they are also designed to be able to reflected radar wave away from the source, same with EOTS
btw F-22 was meant to have similar thing to EOTS but there wasnt enough funding and it was meant to be air superiority fighter only so that part was cut.
Also the radome of F-22, F-35 was coated with some sort of bypass RAM that only allow a certain frequently go in and out, the radar was also canted to reflect enemy radar wave aways other than back to the source
ata wrote:Again and again, another problem - engines. You can't use effective RAM inside of engine nozzle. It means every time I can see part of it - I see it clearly. And of course turbine blades (which are visible from quite a wide angle from the rear) are very radar-bright as well.

someone else already posted information related to engine fan blocker in F-135 and F-119 engine above ( have a look ) , there was info about LOAN nozzle as well
also i dont really think you can see the engine fan from wide angle


ata wrote:Again and again, a
What are the tactical advantages of Su-35? Speed. Range. Radar. Manoeuvrability. Armament. Do you have any question about any of those points? Do you need explanation how every of them could help in a fight? We can discuss.

Top speed of Su-35 is higher than F-35 in clean configuration, what is it top speed when it fully loaded with 10-12 AAM? , what about cruising speed? not faster than F-35 i bet, also since F-35 detect Su-35 much earlier than Su-35 can detect F-35, thus it will have much longer time to accelerate to high speed, altitude to give it's missiles more energy if necessary

Range? : ok, i think Su-35 have better range

Radar? : in theory, if F-35 and Su-35 producers both have access to same level of funding and technology then the su-35 radar should be better because it is bigger, However in reality F-35 program have much higher funding and arguably better technology, as a result it was equipped with modern AESA with really good LPI characteristics, by contrast Su-35 only equipped with PESA radar,
while i still think Irbis-e have better range than APG-81, according to some one else calculatiom here, that may not be the truth
=> APG-81 have better LPI than Irbis-e, which one have better range performance is still to be discussed

Maneuverability : in theory due to TVC su-35 will have better max turn rate, lower wing loading will likely give it better sustain turn performance at high altitude , by contrast F-35 high wing loading will give it better roll rate, dive rate, sustain turn ability at low altitude,
su-27 with 4 AAM have much worse acceleration rate compared to F-16 with similar load out, Su-35 have better engine but it also quite a bit heavier, if you want to load it with 10 AAM do you really think it will out accelerate F-35 with 4-6 internal AAM? i dont think so

Armaments : i really don't see R-77 and R-27 have any advantage over Aim-120D or Meteor, CUDA


ata wrote:
What the tactical advantages of F-35? Stealth. Radar. Optical sensors. And it's clear already there are plenty of question on every of them.

Stealth characteristics : try to argue that Su-35 is more stealthy than F-35 is ridiculous
Radar : ( i dont understand, first you claim Su-35 have advantage in Radar, now you claim the exact opposite)
Optical sensor : Let assume that EOTS is similar to OLS-35, then F-35 still have DAS that give it 360 degree view that is very useful in dogfight, it also have DIRCM that help it fool modern IIR missiles
another advantage of F-35 is ECM : because it have much lower RCS, it's ECM will be much more effective as i have explained several page ago
Last edited by eloise on 12 Apr 2015, 20:03, edited 4 times in total.


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by eloise » 12 Apr 2015, 19:47

ata wrote: I've read that article. And some others as well. LPI is not a magic (as well as stealth) and concept is very clear. Bu again, please read this carefully: "to be detectable for it's own radar level of reflected signal must be at least comparable with noise level. In the meantime power of LPI signal received at target side will be THOUSANDS time higher than reflected back to F-35" - there is only one way how to avoid it. Receivers at F-35 side must the same time more sensitive. In fact thousands times more sensitive. And not simply "more sensitive" but with thousands times higher selecting ability. If they're not, then signal level received at target side will be always higher, and will be detectable easily. And then it's only a question of target radar if it's able to detect it. And I was surprised, but seems like S-300/400 missiles also has this option. So, it's pretty well know technology.

Ok can you give me a an exact source that said the radar signal at the target is several thousand times stronger than reflected signal? because that simply doesn't fit the radar equation at all
secondly, as i have explained, RWR have trouble detect LPI radar not because it doesn't detect the radar signal, or that the radar signal lower than the noise level, but because the LPI signal have little to zero characteristics for RWR to separate it from background noise ( remember the background noise level are not the same all the time so you cant just classified all signal above a certain level is radar signal)
read the part about compression of pulse in the slide i gave you



ata wrote:
Again, it's only a question of distance and processing (because LPI switches frequency), but it's not a big deal anyway.

AESA changing frequency extremely fast, have irregular search pattern, low side lobe, very rapid search speed, it applies pulse compression with irregular pattern so that a pretty big deal if you asl me

ata wrote:
No difference. LPI is still source of signal. All of this also works for F-35 receiving signal from Flanker radar. You can only make any conclusion if you detect the target with your own radar.

no, there are significant differences between an moving air target and a ground stationary target, if you spend even a minute to read the slide, you will understand why RWR can not be used to give firing solution again air target ( same reason why ASQ-213 doesnt make F-16 CJ a super powerful BVR fighter)
ata wrote:
There is also a "detection probability" because even if your beam is 2 degrees thin, at 100 km range it will be 3,5 km spot and because beam's gain is not constant than Flanker must be in the center or close to the center of that spot (3,5 km diameter). If it's not in the center then there is a probability that F-35 will not detect it. BUT, because as I said signal in incoming beam is thousands time higher than in reflected Flanker will detect F-35 even at the edge of that spot.

you know AESA radar scan rate is extremely fast right?

ata wrote:
Let's also talk about plane coming from the side. Why do you think it's invisible? How do you think doppler radar works? First of all, of course that plane will be moving for me, because I'm moving to it! The only problem here is that I can't recognise it for example from the mountain behind it. But that's why modern radars are using impulse+doppler technique. Moreover after two scans I'll be able even make a conclusion about it's speed, because it will move in front of me.

doppler radar on fighter will rejected signal that doesn't have doppler effect on it after taken in to account the speed of the aircraft carried the radar, in fact it will reject slow moving air object as well, otherwise your radar screen will be full of insect, bird, infact if your radar doesn't reject slow moving target then i can just drop a few package of chaff, and you will have like thousands of different targets on your screen for very very long time

ata wrote:
It works like this: you give me a number which is simulated and can't be used in any conclusion and you build your theory on those numbers. But if I give you another number (for example about engines visibility) you say no, it's wrong, let's see our simulation. So, from your numbers there is no one we can take as a basis. NO ONE.

No, I gave you number that USAF claimed, then i gave you number from actually measurement in Have Blue competition, then i gave you the simulation radar scattering graph, and then i use available theory to explain these value
Also i dont invented any theory, the radar equation for example are pretty well known


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by sergei » 12 Apr 2015, 21:17

http://www.fighter-planes.com/stealth2.htm
"(RCS) of a Sukhoi Su-35 fighter"
Source: INTERNATIONAL DEFENSE REVIEW - JANUARY 01, 2004

http://vivovoco.astronet.ru/VV/JOURNAL/ ... STELLS.HTM

" "Фасеточная" модель самолета Су-27 (вверху) и диаграмма эффективной поверхности рассеяния самолета
в зависимости от угла наблюдения в горизонтальной плоскости (внизу) "

"ВЕСТНИК РОССИЙСКОЙ АКАДЕМИИ НАУК

том 73, № 9, с. 848 (2003)"

"su-27 with 4 AAM have much worse acceleration rate compared to F-16 with similar load out"
Su27 2 R73+2 R27 vs F16 4 Aim9, Su27 have advantage in acceleration.
download/file.php?id=20477&mode=view

"1- the exterior airframe of su-27 and su-35 is exactly the same,they made from same material, "


"Airframe generally similar to the Su-27, but when create the su-35 used a new aluminum-lithium alloys, greatly expanded the use of composite materials. "


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by eloise » 13 Apr 2015, 01:41

sergei wrote:http://www.fighter-planes.com/stealth2.htm
"(RCS) of a Sukhoi Su-35 fighter"
Source: INTERNATIONAL DEFENSE REVIEW - JANUARY 01, 2004

http://vivovoco.astronet.ru/VV/JOURNAL/ ... STELLS.HTM

" "Фасеточная" модель самолета Су-27 (вверху) и диаграмма эффективной поверхности рассеяния самолета
в зависимости от угла наблюдения в горизонтальной плоскости (внизу) "

"ВЕСТНИК РОССИЙСКОЙ АКАДЕМИИ НАУК

том 73, № 9, с. 848 (2003)"

what you mean?
sergei wrote:"su-27 with 4 AAM have much worse acceleration rate compared to F-16 with similar load out"
Su27 2 R73+2 R27 vs F16 4 Aim9, Su27 have advantage in acceleration.
download/file.php?id=20477&mode=view


that is again F-16A,, I was talking about F-16 Block 50,* The original Pratt & Whitney engine on the YF-16 developed about 23,000 pounds of thrust. The engines on the Block 50/52 aircraft develop nearly 30,000 pounds of thrust. The GE F110-GE-132 engine on the Block 60 F-16 is rated at 32,500 pounds of thrust.

sergei wrote:"1- the exterior airframe of su-27 and su-35 is exactly the same,they made from same material, "


"Airframe generally similar to the Su-27, but when create the su-35 used a new aluminum-lithium alloys, greatly expanded the use of composite materials. "

they said they expand the use of composite materials, but it doesn't say, they do it at the surface , it is likely that new composite materials is only for internal part, the truth is things that contribute greatly to high RCS on su-27 such as intake, engine fan blade, vertical stablizer, pylon, wing stay exactly the same on Su-35, same shapeand they didn't change the shape or materials for these part


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by sergei » 13 Apr 2015, 08:25

eloise wrote:
sergei wrote:http://www.fighter-planes.com/stealth2.htm
"(RCS) of a Sukhoi Su-35 fighter"
Source: INTERNATIONAL DEFENSE REVIEW - JANUARY 01, 2004

http://vivovoco.astronet.ru/VV/JOURNAL/ ... STELLS.HTM

" "Фасеточная" модель самолета Су-27 (вверху) и диаграмма эффективной поверхности рассеяния самолета
в зависимости от угла наблюдения в горизонтальной плоскости (внизу) "

"ВЕСТНИК РОССИЙСКОЙ АКАДЕМИИ НАУК

том 73, № 9, с. 848 (2003)"

what you mean?
sergei wrote:"su-27 with 4 AAM have much worse acceleration rate compared to F-16 with similar load out"
Su27 2 R73+2 R27 vs F16 4 Aim9, Su27 have advantage in acceleration.
download/file.php?id=20477&mode=view


that is again F-16A,, I was talking about F-16 Block 50,* The original Pratt & Whitney engine on the YF-16 developed about 23,000 pounds of thrust. The engines on the Block 50/52 aircraft develop nearly 30,000 pounds of thrust. The GE F110-GE-132 engine on the Block 60 F-16 is rated at 32,500 pounds of thrust.

sergei wrote:"1- the exterior airframe of su-27 and su-35 is exactly the same,they made from same material, "


"Airframe generally similar to the Su-27, but when create the su-35 used a new aluminum-lithium alloys, greatly expanded the use of composite materials. "

they said they expand the use of composite materials, but it doesn't say, they do it at the surface , it is likely that new composite materials is only for internal part, the truth is things that contribute greatly to high RCS on su-27 such as intake, engine fan blade, vertical stablizer, pylon, wing stay exactly the same on Su-35, same shapeand they didn't change the shape or materials for these part

Earlier in the international air under the symbol "Su-35" was exhibited aircraft Su-27M.
"ВЕСТНИК РОССИЙСКОЙ АКАДЕМИИ НАУК" - Bulletin of the Russian Academy of Sciences
Lagarkov Andrey - corr. Russian Academy of Sciences, Director of the Institute of Theoretical and Applied Electrodynamics, Joint Institute for High Temperatures.
Mikhail Pogosyan - corr. Russian Academy of Sciences, Director of "Sukhoy ".
http://vivovoco.astronet.ru/VV/JOURNAL/ ... STELLS.HTM
Source much more reliable than http://www.fighter-planes.com/info/su35.htm ,data relied upon by your magazine it
some strange mix of Su-27,Su-37,Su-35 and Chengdu J-10b(J-10B: An upgraded variant of the J-10 from 2008) with engine never exist (AL-31MF)
" I was talking about F-16 Block 50"
F-16A/ F-16 Block 50
Thrust 23,800 lbf/28,600 lbf Max. takeoff weight: 37,500 lb/42,300 lb Loaded weight: 26,500 lb
Thrust/weight: 0.6346/0.676 1.079
Su-27/Su-35
Thrust 27,700 lbf/31,900 lbf Max. takeoff weight: 67,100 lb/76,060 lb Loaded weight: 56,660 lb
0.8256/0.8388 1.26
And Su35 have advantage in acceleration vs F-16 Block 50

" it is likely that new " You heard about this for the first time from me and you already know what and where it was applied? :drool:

"what about cruising speed? not faster than F-35 i bet"
If my memory serves me something like 0.85m+ for F35 and 1.01 for Su-35


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