FGFA / PAK-FA (T-50) Vs F-35 JSF

[jagjitnatt]

I wouldn't say PakFa is more advanced or powerful than F35. Its a different aircraft with a different strategy.

Where F22 and F35 would try to use stealth as its advantage, they would be compromising on maneuverability and weapon capacity.

PakFa gives up a bit of its stealth characteristics to gain more maneuverability and weapon capacity. It has a powerful radar and focuses more on detecting the other aircraft and negating their stealth advantage.

PakFa won't be anywhere near the JSF in stealth but would be able to detect it at distances where JSF would still be unaware about PakFa's position.

Also radar can be fooled by using RAM coatings and stealth design but IR signature is something that is unavoidable. These machines are burning fuel at an unbelievable rate, which emits an IR signature that no amount of technology can hide today.

Russia is very good with its IRST and believes it would be the next alternative to radar and its true since radar would be the tool of the past with 6th gen planes.

An improved IRST would be very potent tool to locate aircraft like F35 in air. Also IR guided missiles are evolving rapidly, they are way more maneuverable, which increases the chance of a kill. Also latest IR missiles like ASRAAM can differentiate a flare from a plane. If Russia work out an intelligent missile like this, then its game over for F35.

The biggest problem with JSF is that its grossly underpowered. With a thrust to weight ratio of 0.84, its really a lazy plane. PakFa is supposed to be powered by two engines of 175KN of thrust. Even if it is powered by AL41F with 157 KN of thrust, its thrust to weight ratio comes to be 1.22. If 175KN engines are used it would be upped to 1.4 Now that is POWER.

Overall the game is very interesting. The two fighters use different strategies for combat and only a real fight would be able to answer all our questions. But today, I would like to put my money on the PakFa.

 

[dbc]

I wouldn't say PakFa is more advanced or powerful than F35. Its a different aircraft with a different strategy.

Where F22 and F35 would try to use stealth as its advantage, they would be compromising on maneuverability and weapon capacity.

PakFa gives up a bit of its stealth characteristics to gain more maneuverability and weapon capacity. It has a powerful radar and focuses more on detecting the other aircraft and negating their stealth advantage.

PakFa won't be anywhere near the JSF in stealth but would be able to detect it at distances where JSF would still be unaware about PakFa's position.

Also radar can be fooled by using RAM coatings and stealth design but IR signature is something that is unavoidable. These machines are burning fuel at an unbelievable rate, which emits an IR signature.

Russia is very good with its IRST and believes it would be the next alternative to radar and its true since radar would be the tool of the past with 6th gen planes.

An improved IRST would be very potent tool to locate aircraft like F35 in air. Also IR guided missiles are evolving rapidly, they are way more maneuverable, which increases the chance of a kill. Also latest IR missiles like ASRAAM can differentiate a flare from a plane. If Russia work out an intelligent missile like this, then its game over for F35.

The biggest problem with JSF is that its grossly underpowered. With a thrust to weight ration of 0.84, its really a lazy plane. PakFa is supposed to be powered by two engines of 175KN of thrust. Even is it is powered by AL41F with 157 KN of thrust, its thrust to weight ratio comes to be 1.22. If 175KN engines are used it would be upped to 1.4 Now that is POWER.

Overall the game is very interesting. The two fighters use different strategies for combat and only a real fight would be able to answer all our questions. But today, I would like to put my money on the PakFa.

Well I agree the F-35 is no where near the PAK-FA when you talk about engine power, thrust to weight ratio, antenna size and power ..the Pak-Fa numbers are impressive.

 

[jagjitnatt]

Well I agree the F-35 is no where near the PAK-FA when you talk about engine power, thrust to weight ratio, antenna size and power ..the Pak-Fa numbers are impressive.

btw is it you in the avatar?

 

[dbc]

btw is it you in the avatar?

Are you done talking about the PAK-FA? So far you've talked about IRST, Radar, engine and maneuverability - surely there is more?

 

[duhastmish]

its not fair to compare jsf and pak-fa.

pak-fa is twin engine fighter with a totally diffrent use, its a heavy fighter.

btw right now its lame to even comapre the pak-fa to anythign because not much info ( avionics is known).

but someday i would like to compare it to f-22 not jsf.

and by that time - may be american 6th gen fighter will be almost on taxi run.

 

[dbc]

In terms of rhetorics from the manufacturer and 'fanboy' ravings. We stand no chance against these forces.

stay strong gambit

 

[dbc]

btw is it you in the avatar?

nah! she is a USAF pilot just a subtle remainder for some folks here that women can mix it up with the best of the best...

 

[notorious_eagle]

stay strong gambit

Yup this gentlemen claimed in another thread that Pak Fa was superior to F22, i didnt even bother replying since i honestly didnt had the energy to waste my time with a fanboy.

 

[jagjitnatt]

Are you done talking about the PAK-FA? So far you've talked about IRST, Radar, engine and maneuverability - surely there is more?

I can write pages and pages on it. Its just my fingers start hurting after doing my pending work at office. I have a habit of doing things right before the deadlines, sometimes after the deadlines.

 

[notorious_eagle]

I can write pages and pages on it. Its just my fingers start hurting after doing my pending work at office. I have a habit of doing things right before the deadlines, sometimes after the deadlines.

Join the Club , i guess procrastinating runs deep in our Brown Blood

 

[Thomas]

It remains to be seen at what range the T-50 will be able to engage an F-35. Radar and maneuverability are just some of the factors. The F-35 has a very impressive EW suite

Avionics Magazine :: F-35 Electronic Warfare Suite: More Than Self-Protection

"At the EW system level, the F-35 will about equal the F-22 in performance, Branyan predicts. But because the newer aircraft's EW suite was developed from the start for reliability and affordability, it promises twice the reliability at half the cost, compared with legacy aircraft."

 

[dbc]

I guess someone needs to take a nice look at this Look at Irbis E radar that is used in Mig-35. It might be the next upgrade for the Su30MKI. The Irbis E radar is twice as effective as Bars radar. That would dwarf the APG-77 and APG-81 radars. Also PakFa's radar is supposed to be more powerful than this. Also IRST in Pak Fa is superior. Russians are way advanced when it comes to IRST. JSF's detection capabilities would be no where near PakFa's. But JSF could make up for it with its superior stealth.

You claim that the PAK-FA radar is “more powerful” and will "dwarf" the APG-77, but you forget that power is wasted if it isn’t channeled correctly – there is no exception to this rule. Competent radar makers invest serious money into refining their designs and manufacturing process to contain the radiated energy within the mainbeam and reduce energy leak into the sidelobe.

At this point some may wonder what is “mainbeam” and “sidelobe” details can found on wiki OR Gambit has posted a better more comprehensive explanation right here on PDF (I can’t remember the thread). Even if you don’t bother to look up these terms or have a short attention span or don’t care – just remember this “mainbeam good – sidelobe bad”. Sidelobes are the biggest contributors to exposure and increase the likelihood of detection. High sidelobe level make a radar more susceptible to jamming and false signals.

First sidelobes of the order of -35 db -40 db below the mainbeam is practically achieved by most modern western radars. For comparison the older APG-66 radar on the F-16A presents the first sidelobe at -25db this is identical to the N011M Bars on the SU-30MKI. For a radar to qualify as a LPI(low probability of intercept) radar the main beam gain of +55db is necessary but sidelobes in the range of -50 to -55db is difficult to achieve, extreme manufacturing tolerance is required - making such radars prohibitively expensive for most countries. The sidelobe figure for the APG-77 is rumored to be much lower than -55db some online enthusiast speculate it is closer to -70db. In contrast, the best production radar made by the Russians ZHUK-AE is credited with -30db this is a non-conservative estimate. The F-22 is expensive due to the high standards and precise manufacturing required to build the components that go into the Raptor.

If the Russians want to build a “Raptor killer" they will have to spend a lot more than they’re spending on the PAKFA - it is that simple

The low element count will be reflected in sidelobe performance, to the extent that a relatively sparse array like the Zhuk AE design is inherently much more sensitive to phase and amplitude errors in the array TR channels, compared to more dense arrays. This is difficult to assess accurately in the absence of performance data for the phase and amplitude error correcting mechanisms embedded in the array. If they perform well, this may not prove to be an issue, if not, sidelobe performance cited at -30 dB may be difficult to maintain.

Phazotron Zhuk AE: Assessing Russia's First AESA

 

[gambit]

First sidelobes of the order of -35 db -40 db below the mainbeam is practically achieved by most modern western radars. For comparison the older APG-66 radar on the F-16A presents the first sidelobe at -25db this is identical to the N011M Bars on the SU-30MKI. For a radar to qualify as a LPI(low probability of intercept) radar the main beam gain of +55db is necessary but sidelobes in the range of -50 to -55db is difficult to achieve, extreme manufacturing tolerance is required - making such radars prohibitively expensive for most countries. The sidelobe figure for the APG-77 is rumored to be much lower than -55db some online enthusiast speculate it is closer to -70db. In contrast, the best production radar made by the Russians ZHUK-AE is credited with -30db this is a non-conservative estimate. The F-22 is expensive due to the high standards and precise manufacturing required to build the components that go into the Raptor.

If the Russians want to build a “Raptor killer" they will have to spend a lot more than they’re spending on the PAKFA - it is that simple


Phazotron Zhuk AE: Assessing Russia's First AESA

To clarify for interested readers about this 'db' measurement...

In 'db'...The 'd' stands for deci meaning 10. The 'b', or actually capital 'B', is to respect some historically obscure dude named Alexander Graham Bell. So technically speaking it should be 'dB'. But no one will go into an apoplectic fit, least of of all Alex himself, if the usage is simply 'db', or decibel.

A 'dB' is a measurement of a RATIO between two numbers. The values are not important. This ratio is logarithmic...Like so...

0.0001 = -40dB
0.001 = -30dB
0.01 = -20dB
0.1 = -10dB
1 = 0dB
10 = 10dB
100 = 20dB
1000 = 30dB
10000 = 40dB

And so on in either direction...

In radar detection, the main beam or main lobe is usually '1' and the sidelobes, or sidebeams, are %99 of the time undesirable. Only in extreme circumstances are sidelobes exploited and those situations are outside of the general scope of discussion at this time. Unfortunately, sidelobes are also unavoidable. As stated, manufacturing processes are crucial in creating an antenna with very low sidelobes. So if we go by the brief scale above, the goal is to have as great the power difference gap between the main lobe, which would be '1', and the sidelobes, which SHOULD BE in the negative figures. The higher the negative figures, the better. After all, in radar detection, %99 of the time, it is information from the main lobe, or main beam, that matter. Sidelobe information is distracting. There are unique situations where information from the main lobe, or main beam, is actually discarded and only information from the sidelobes info are used, but those situations are so far out of the norm they are beyond the scope of this discussion.

ECM tactics often target the sidelobes as, in a manner of speaking, they are legitimate scanning beams. They just are undesirable. Do not confuse legitimacy with being unwanted. But because the wanted is the main beam, sidelobes are often targeted by ECM tactics to confuse the system as it must now allocate resources to discriminate information between the unwanted beams and the main beam. Therefore, since sidelobes are unwanted, the weaker the sidelobes the less distance they can travel from the aircraft and that make the radar system more resistive to ECM tactics.

Sidelobe Blanking

Antennas with poor sidelobe performance can be improved by using sidelobe blanking (SLB) techniques. Even antennas with good sidelobe performance can benefit from sidelobe blanking especially in the presence of jamming. In sidelobe blanking, a second antenna (an omnidirectional antenna) is set-up near the main radar antenna.
The role of this second antenna is to alert the system to the presence of jamming. An important point to note is that the omnidirectional antenna has a gain higher than that of any of the radar antenna sidelobes. The main antenna drives the radar display through a switch arrangement. If more energy is coming through the omnidirectional antenna than through the main antenna, the switch prevents any radar information from being displayed.

Fighter aircrafts are limited inside the radome so a second antenna to perform sidelobe blanking is highly discouraged. In sidelobe blanking, if that second antenna detect ECM tactics, the main antenna is basically shut off from the pilot, rendering the entire radar system momentarily useless. Not what the pilot want.

Sidelobe Cancellation

Sidelobe cancellation (SLC) is a little more sophisticated than sidelobe blanking. Remember that successful jamming for an extended period renders a radar using sidelobe blanking effectively useless for the period of the jamming. The operator knows the direction of the jamming but is blind to valid targets throughout the jamming period. Sidelobe cancellation (SLC) avoids this problem and allows the radar system to remain functional in the presence of jamming.

Sidelobe cancellation is pretty much standard feature in just about all radar systems.

So it is clear that the greater the negative 'db' value between the side lobes that flanked the main lobe, as shown in the image above, the less time and computing resources the system must allocate to perform sidelobe cancellation. Therefore the better the seeking radar system.

Note: Sidelobe powers cannot be greater than '1'. If any manufacturer does produce such an antenna, he should be castrated with a dull spoon by a man-hating, Harley-riding butch lesbian.

 

[ptldM3]

Chocolate the ZHUK-AE is not the the radar intended for the pak-fa. BTW i'm not a fan of these comparison thead esspecially when so little information is known, these threads are fan boy bait.

 

[KEETARP]

When we talk of modern Phased Array system operating in LPI mode , i think already their BACK-LOBES + SIDE-LOBES are quite less.
And thats achieved bcoz wave-shifters delay the signal by just amount to steer the beam in a very precise way to a Specific direction.
Thereby increasing the sharpness of wave than main-lobe itself by canceling components in other direction.

.

Wave beam in Other direction has very liitle component bcoz of Destructive interference.

Now see the strength of component in perpendicular direction to main beam , there are two small lobes means Very low 90-degree side-lobe achieved by 2 antennae units . When you have 1200-2000 Transmitter grids , this sharpness increases even more by destructive interference in more planes

Just my logic- Can be a Blunder though