T-50 versus the F-35

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14 years 6 months

Posts: 8,850

As I said - 'overall' RCS figure makes no sense. For example - average Flanker's RCS from the side is closer to 40 m2, nose on - 20 m2. The most important is frontal sector RCs, so I think they're refering to frontal RCS which we know that is ~20m2.

I bet you have good sources for this... Please, provide for all to see.

BTW, the value of 0.5sqm for PAK-FA comes from Pogosyan and he himself described it as an "average frontal value". Whatever that means, it surely is not a value of a carefully handpicked corner with 0.0000x sqm value just like F-22 fans love to quote.

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15 years 10 months

Posts: 6,983

Not claiming to be clairvoyant, but i would guess the "200 km" refers to max,
while it refers to a more reasonable 100 km useful range vs a modern fighter equippet with modern MAWS,
i believe this will be achievable in 10 years.
I also believe that the very best a "LPI radar" can hope to achieve is to not give away the exact location at longer range then it can detect anything itself, given roughly tecnological parity.

Member for

14 years 6 months

Posts: 8,850

Not claiming to be clairvoyant, but i would guess the "200 km" refers to max,
while it refers to a more reasonable 100 km useful range vs a modern fighter equippet with modern MAWS,
i believe this will be achievable in 10 years.
I also believe that the very best a "LPI radar" can hope to achieve is to not give away the exact location at longer range then it can detect anything itself, given roughly tecnological parity.

MAWS detects signals. That means output power of LPI radar - loss on the way.

LPI radar has to detect return of its own signal bounced off from the target's surface. That means output power of LPI radar - loss on the way - scatter and absorption on the surface - loss on the way back.

MAWS is always in advantageous position. With low observable designs the advantage becomes pretty enormous due to large losses on the RAM-treated surface. LPI can outtrick vintage systems but if we assume technological parity and identical sensitivity of detectors of both radar and MAWS, then I'd say that an LPI radar has zero chance to detect without being detected.

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17 years 5 months

Posts: 4,042

MAWS detects incoming missiles, not radar signals(that's RWR and ESM). If we assume parity/identical capabilities, then all sorts of claims can be made about either radars, or RWRs. Seeing as how both of these are sensitive technologies, where not much is known in terms of the true capabilities/limitations, I would be hesistant to assume parity exists.

As for LPI, yes RWR detects signals, but you're ignoring the fact that it also filters signals. Whether or not the filter correctly identifies the LPI signals is another matter, and if so under what conditions/with what degree of probability/what degree of accuracy.

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15 years 9 months

Posts: 6,441

Not claiming to be clairvoyant, but i would guess the "200 km" refers to max,
while it refers to a more reasonable 100 km useful range vs a modern fighter equippet with modern MAWS,
i believe this will be achievable in 10 years.
I also believe that the very best a "LPI radar" can hope to achieve is to not give away the exact location at longer range then it can detect anything itself, given roughly tecnological parity.

If an Interceptor aka Mig-31 or Su-35S can carry long range missiles.
Doesn't it makes sense to have a radar powerfull enough to paint a target from a huge distant that simply out perform the adversery radars and kenetics?

I know a stealth adversery will change the rules here.

But i think the statment above isn't too far away from the truth.
At least its how the RuAF see things until the Pak-Fa enter operation.
There isn't many operational stealt adversery bar the F-22A and B-2.
And they are USAF, so its completly unlikely they will face each other.

Which again brings us back to my statment above..

Thanks

Member for

19 years 11 months

Posts: 1,856

As I said - 'overall' RCS figure makes no sense. For example - average Flanker's RCS from the side is closer to 40 m2, nose on - 20 m2. The most important is frontal sector RCs, so I think they're refering to frontal RCS which we know that is ~20m2.

Rofl...

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14 years 6 months

Posts: 408

Rofl...

What's so funny?

Member for

19 years 11 months

Posts: 1,856

What's so funny?

If it isn't obvious... there's no point.

Member for

14 years 10 months

Posts: 1,741

i guess the indians dont know the rcs of their own planes

http://www.business-standard.com/india/news/india-russia-close-to-pactnext-generation-fighter/381718/
Sukhoi’s FGFA prototype, which is expected to make its first flight within weeks, is a true stealth aircraft, almost invisible to enemy radar. According to a defence ministry official, “It is an amazing looking aircraft. It has a Radar Cross Section (RCS) of just 0.5 square metre as compared to the Su-30MKI’s RCS of about 20 square metres.”
That means that while a Su-30MKI would be as visible to enemy radar as a metal object 5 metres X 4 metres in dimension, the FGFA’s radar signature would be just 1/40th of that.

Member for

19 years 11 months

Posts: 1,856

i guess the indians dont know the rcs of their own planes

http://www.business-standard.com/india/news/india-russia-close-to-pactnext-generation-fighter/381718/
Sukhoi’s FGFA prototype, which is expected to make its first flight within weeks, is a true stealth aircraft, almost invisible to enemy radar. According to a defence ministry official, “It is an amazing looking aircraft. It has a Radar Cross Section (RCS) of just 0.5 square metre as compared to the Su-30MKI’s RCS of about 20 square metres.”
That means that while a Su-30MKI would be as visible to enemy radar as a metal object 5 metres X 4 metres in dimension, the FGFA’s radar signature would be just 1/40th of that.

What angle?

Who measured it?

Member for

15 years 7 months

Posts: 567

i guess the indians dont know the rcs of their own planes

http://www.business-standard.com/india/news/india-russia-close-to-pactnext-generation-fighter/381718/
Sukhoi’s FGFA prototype, which is expected to make its first flight within weeks, is a true stealth aircraft, almost invisible to enemy radar. According to a defence ministry official, “It is an amazing looking aircraft. It has a Radar Cross Section (RCS) of just 0.5 square metre as compared to the Su-30MKI’s RCS of about 20 square metres.”
That means that while a Su-30MKI would be as visible to enemy radar as a metal object 5 metres X 4 metres in dimension, the FGFA’s radar signature would be just 1/40th of that.

It's a Russian aircraft. Not an Indian aircraft. Any RCS measurements would have come from Russia. Also, RCS varies with greatly frequency, polarization, and of course, what angle you view the aircraft from. It also depends on how you quantify the RCS- do you refer to head on X-band RCS? Do you refer to head on RCS averaged over a range of frequencies? Or perhaps average over all angles.

Keep in mind that the Russians give a 0.3 m^2 RCS for the Raptor- this alone should tell you that you should not compare the given (and very questionably factual) 0.5 m^2 figure to the publicly available 0.00001 m^2 figure given for the F-22's frontal RCS. Unless the 0.5 m^2 is misinformation (a reasonable chance), it is plain to see that RCS is being quantified differently by Sukhoi. Or more likely, they just make up public RCS numbers and keep the real data close to their chest.

Also, Sukhoi also gave the Su-47 rcs as 0.3 m^2 in 2002. The Eurocanards, and Super Hornet are usually given in the 0.1-0.5 m^2 range as well.

All this being said, the 0.5 m^2 number is VERY fishy.

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18 years 11 months

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DIONIS,

why so hostile ? Its not nice to try to shut this thread every step of the way just cause you don't like it.

Member for

14 years 6 months

Posts: 408

If it isn't obvious...

I'll tell you what's obvious - you have no clue about Flanker's RCS but you mock me. Funny.:rolleyes:

Member for

14 years 10 months

Posts: 1,741

Erkokite
0.5 is the number the russians and india are using, at this stage there is nothing to say they are wrong or misleading
as soon as india takes it to red flag or there is an exercise in india, then everyone can have a look
i'm sure a lot of pilots will line up for a back seat ride too

Member for

15 years 7 months

Posts: 567

Erkokite
0.5 is the number the russians and india are using, at this stage there is nothing to say they are wrong or misleading
as soon as india takes it to red flag or there is an exercise in india, then everyone can have a look
i'm sure a lot of pilots will line up for a back seat ride too

This is not the number they are "using." This is an unofficial number that someone heard from an Indian MoD official who supposedly heard it from a PAK-FA technician. Any actual RCS data will be kept classified. There is nothing official about this number.

And as I said, 0.5 m^2 is likely nonsense because the Su-47 achieved 0.3 m^2 in the 1990's, despite it having the front fuselage of a Su-27 and not being a 100% new design aircraft. There was no chining, nor planform alignment on the Su-47. Stealth shaping on the Su-47 was quite minimal. I've heard that the Mig-29SMT has an RCS of around 0.5 m^2 (presumably frontal, X-band). I've heard the Su-35 has an RCS of around 1 m^2.

There is no indication of what this 0.5 m^2 even means- does it mean average RCS? What frequency is it at? Does this include RAM coatings or blockers? Is it for the prototype, which has unfinished nuts/bolts showing in places, lacked RAM coatings and the final engine and nozzle, or is it the final model?

In addition the 0.5 m^2 claim may be confused as it seems to come from the claim that the T-50 has a 40x smaller RCS than the Su-30MKI, which could also mean a -40 dbsm reduction rather than a 40x reduction, which is significantly greater. There was a good discussion over on secret projects about it.

We have no idea of the veracity of the 0.5 m^2 figure and even if it is true, we have no idea what context it is in. The 0.5 m^2 simply doesn't make any sense without more information.

But, as you say, we'll have to wait until there are exercises with the PAK-FA, which should be interesting. But even then, they will likely fly with reflectors the way the F-22 often does today in exercises. Probably the closest we could get to actual numbers would be for someone to run an RCS simulation on the aircraft, but this also isn't a whole lot of good because unless we know where the RAM is placed, or have a good idea of what materials are used where, we are unlikely to get a terribly accurate answer.

Member for

24 years 8 months

Posts: 5,396

If it isn't obvious... there's no point.

The point revealed by your comment is that you have no clue about Flanker's RCS.

Member for

14 years 10 months

Posts: 1,741

ok it's the jurno was told by Indian MoD official who was told by a PAK-FA technician
i'm sure it wont be the last quote for its rcs and as i said red flag or indian exercises will give everyone an idea
russia wanted to sell the su-30 to australia, ya never know, we may buy the PAK

Member for

24 years 8 months

Posts: 5,396

What angle?

Who measured it?


USAF measured the Flankers they bought from Belarus in 1994. We can guess that those measurements established a baseline for RCS estimates of Flanker upgrades.

Member for

19 years 11 months

Posts: 1,856

DIONIS,

why so hostile ? Its not nice to try to shut this thread every step of the way just cause you don't like it.

This thread is a joke. The facts are clear. The speculation is worthless.

I'll tell you what's obvious - you have no clue about Flanker's RCS but you mock me. Funny.:rolleyes:

But you pretend to know it? Give me a break.

Member for

19 years 11 months

Posts: 1,856

USAF measured the Flankers they bought from Belarus in 1994. We can guess that those measurements established a baseline for RCS estimates of Flanker upgrades.

So the Indian MoD quoted the US figures?

Who is to say they are accurate - upon what has been released that is.