J-20 5th Gen Fighter Thread VIII

[ismellcopium]

I assume you mean something like "extraordinary" instead of "exaggerated"?

He's definitely just translating something like 特别夸张 literally, so yeah.

It's hard for me to even imagine the capabilities of this radar if anything remotely like double J-20's range is true, given the latter should already be among the most powerful/capable deployed.

 

[Alfa_Particle]

He's definitely just translating something like 特别夸张 literally, so yeah.

It's hard for me to even imagine the capabilities of this radar if anything remotely like double J-20's range is true, given the latter should already be among the most powerful/capable deployed.

Hope they also did some upgrading work with the LPD/LPI side which is just as important as sheer range.

 

[Aval]

That's at least a tracking range of 300km vs 1m2 target then....

J-20 has the largest radar aperture of all the 5th gen fighters, so even if OG radar was based on GaAs, it should rival the AN/APG-77 in range.

300km tracking vs 1m2 is a very conservative estimate, it's prolly higher.

300km against 1m^2 is ludicrous. If this is the range with lock-quality targeting, its probably at the practical limits of the PL-15 even against stealth fighters and already bottlenecked by the PL-15 against all others. A shame Yankee didn't have any news on the PL-16 for us this time around.

Its hard to believe this is radar performance possible on a 5th-gen fighter unless its internal cooling architecture and plumbing was significantly reworked, but I suppose that is actually what happened with the J-20A based on some of the rumours circulating.

Of course, this also asks the question: What would the J-36 radar range be like? That thing has an even bigger radar aperture. The J-36 may be able to natively make full use of PL-17 -class missiles' range against stealth targets even without AWACs support.

 

[Tomboy]

300km against 1m^2 is ludicrous. If this is the range with lock-quality targeting, its probably at the practical limits of the PL-15 even against stealth fighters and already bottlenecked by the PL-15 against all others. A shame Yankee didn't have any news on the PL-16 for us this time around.

300km tracking against 1m2 target is really only 54km against a 0.001m2 target. The range further drops to only 40km for a -35dBsm target and 30km for -40dBsm. Against stealthy targets, the radar is still definitely the bottleneck here. Which is why AEWC support is still absolutely critical against stealthy targets.

 

[sequ]

Of course, this also asks the question: What would the J-36 radar range be like? That thing has an even bigger radar aperture. The J-36 may be able to natively make full use of PL-17 -class missiles' range against stealth targets even without AWACs support.

It could potentially use a C-band radar (side radars still X-band imo), as a PL-17 is big enough to carry a powerful radar seeker to offset the lower resolution of the C-band radar.

And add to that the humongous EO 'eyes'.

 

[tphuang]

Thanks for taking your time to translate.

Guess rumors of J-20A radar doubling the range of that of the basic model is true after all.

They actually said triple.

300km tracking against 1m2 target is really only 54km against a 0.001m2 target. The range further drops to only 40km for a -35dBsm target and 30km for -40dBsm. Against stealthy targets, the radar is still definitely the bottleneck here. Which is why AEWC support is still absolutely critical against stealthy targets.

Due to earth curvature, signal processing and such, it is entirely possible things don’t scale that way. Also passive sensors and EO sensors don’t scale the same way either.

It could potentially use a C-band radar (side radars still X-band imo), as a PL-17 is big enough to carry a powerful radar seeker to offset the lower resolution of the C-band radar.

And add to that the humongous EO 'eyes'.

What side radars?

 

[Blitzo]

What side radars?

They were responding to a question about J-36's radar in this thread (which is off topic). They are referring to J-36's suspected side radars.

 

[siegecrossbow]

300km tracking against 1m2 target is really only 54km against a 0.001m2 target. The range further drops to only 40km for a -35dBsm target and 30km for -40dBsm. Against stealthy targets, the radar is still definitely the bottleneck here. Which is why AEWC support is still absolutely critical against stealthy targets.

There are no 0.001m2 targets though, at least not for fifth gen. Outside frontal and rear cone with optimized RCS the result is fairly ugly.

 

[Totoro]

But the mission is always managed so the frontal cone, which can sometimes be 90 degrees wide, between the two big spikes that are wing's radar returns, is the one that is presented to the enemy. So as long as the plane is a few hundred km away from enemy perimeter, even the side views may not get to be outside the said cone. Plus the more to the side you are, the greater distance to the object you are looking at is gonna be. So even partial stealth there may be enough.

All this may be enough that long range aa missiles and stand off ag weapons are used. But all this is really for another topic. No one wants discussion to veer off into off topic.

 

[Tomboy]

There are no 0.001m2 targets though, at least not for fifth gen. Outside frontal and rear cone with optimized RCS the result is fairly ugly.

Yes there are, F-35 is said to have the RCS of a golfball sized target in the frontal aspect which is roughly -30dBsm. As @Totoro mentioned, a competently planned mission will attempt to keep the enemy in the frontal cone as much as possible.