J-10 Thread III (Closed to posting)

[Engineer]

So it's not aliasing. You can tell it's a PESA because on an AESA, all the modules are identical, but on this PESA, you have what are apparently holes on a horizontal line.

Those are not holes, as they cast shadows indicating that they stick out of the antenna. There is no indication that they are modules, either. If your premise that the new radar can't be an AESA because of existence of that row of unknowns, then by the same logic it can't be a PESA because Irbis-E doesn't have that row of unknowns either.

 

[tanlixiang28776]

Siegecrossbow: this is what I mean by SDF being overly optimistic about Chinese military technological advancements. Let's just all accept that J-10B in the picture uses PESA, and that in the future it may be outfitted with AESA.

It takes time for manufacturing advancements to translate to actual products. We've all heard about the Chinese technological breakthrough in engine metallurgy, but we have no evidence of a WS-10B in use on the J-10 or the J-11B. It's likely that the technology only brings the Chinese up to the current level of the West, but it's something.

Or how you are overly pessimistic about Chinese Military developments. We do not accept that the J10B uses a PESA because Chinese have never made a PESA in any active military project. AESA has been observed on sea, land, and air platforms in active service with the Chinese military.

Not much about WS 10B but WS 10A is active on J 11B and J 15. As for AESA only US actually produces any fighter based ones in active service. Eurofighter waits until 2015, and rafale 2012.

 

[plawolf]

Those are not holes, as they cast shadows indicating that they stick out of the antenna. There is no indication that they are modules, either. If your premise that the new radar can't be an AESA because of existence of that row of unknowns, then by the same logic it can't be a PESA because Irbis-E doesn't have that row of unknowns either.

I would not place any weight on Inst's arguments since he proclaimed the radar was PESA before there was any semblance of evidence to support it, and based on things he could not have possibly been able to make out.

He first suggesting that its PESA because the individual modules were bigger on PESA than AESA when the first blurry pictures came out when the resolution was so poor you can barely make out the actual shape of the radar dish, and then moving on to suggest PESA based on the 'backing', which again he could not see since its not on any of the pictures and so on.

This is a classic example of someone looking for evidence to back up his pre-formed opinions instead of someone looking at facts to try and form an opinion.

 

[Engineer]

I'm not doubting that the Chinese will eventually master the AESA technology, but from what we've seen right now, the J-10 is on AESA, and the Chinese AESAs are at best at parity with Russian AESAs, and the picture we've seen shows that the J-10B in the picture uses a PESA radar.

Maybe on a J-10C upgrade? Or a J-10B2 MLU?

First, there is no evidence that Chinese has not yet mastered AESA technology, because you can found AESA on air, sea and land platforms. There aren't as many AESA radars in service in Russian military by comparison. The reality is that Russian AESA technologies are as best at parity with the Chinese, not the other way around.

Second, this picture does not conclude whether the new radar on the J-10b is AESA or PESA. There is not enough resolution to resolve any details. Your premises basing on these details are thus invalid.

I don't think there's any definitive indication that the Chinese have broken through the AESA problem as of yet, however.

KJ-2000, KJ-200, Type 305A 3D Acquisition Radar, Type 348 and its derivative now being found on the Varyag. Chinese produced AESA radars are in serial production and in service, end of story.

Remember, Chinese semi-conductors are around 7-10 years behind the West, SMIC had to import IBM's antiquated 45nm technology for its latest chips, and Loongson does not yet have a domestic fab.

APG-77 is also at least 7-10 years behind the latest technologies, because it was in serial production beginning in 1999. By your own logic, if China latest semi-conductor technologies are 7-10 years behind the latest in the West, then China today is fully capable of serial production of AESA radars for fighters. In any case, contrary to popular beliefs, latest technologies have little relevance to that what already produced.

Of course, this is China and things move very quickly, but I strongly assert that at this point in time, the Chinese cannot produce an economical AESA radar to the point where it would be worthwhile to staple one onto a J-10B.

So are you arguing China does not have the capability of producing AESA radar for fighters or are you arguing it is not economical to put an AESA onto the J-10? It seems like you are doing a grape shot here... just throwing out incoherent arguments hoping one sticks.

 

[Engineer]

For example, the WS-10 has been in the works for more than a decade, yet the WS-10A has only been recently inducted onto the J-15s, and the engine is still not ready to equip J-10As by itself. All the pictures we've seen show the J-10B carrying AL-31s, so at least in the engines we can see you're being overoptimistic about Chinese technological capabilities.

J-10A isn't equipped with WS-10A because J-10A is a production model. That is, it has already left the design table long ago. Consequently, R&D has no meaning to the plane whatsoever. And whoever said J-10 would ever get equipped with WS-10A at all?

Meanwhile, no concrete information is available on AESA for either the J-10B or the J-11B, although it's likely that the J-11B would receive AESA units as soon as Chinese technology is ready. We are only guessing that the J-20 has an AESA, but it's not completely improbable that the Chinese engineers will miss the milestone and end up putting PESA into the earliest variants.

Why would China come up with PESA if they already have AESA technologies?

Remember, up to now, the J-10As were using Russian radar, and the JF-17 was on a Chinese pulse doppler radar.

J-10A uses Chinese radars.

We have no indication as of yet that Chinese fighter AESA radars are ready for deployment.

This might be the indication:

 

[Inst]

Tanlixiang:

No, the Japanese have the F-2 with an AESA radar inferior to actual PESAs. It's typically overpriced, of course.

Engineer, to your statement regarding the antenna shadows, go look back at the pictures of PESA someone else posted. There were antenna on the PESA, among the receiver modules. AESA doesn't need visible antenna, because each module is both transmit and receive.

plawolf, read what I posted. I said it was PESA because the modules were smaller than AESA antenna, which could result in aliasing, resulting in the horizontal line. Modern PESA has much smaller modules than AESA since PESA modules only have to receive, not transmit. On the picture shown there, you couldn't see the row evident there, it could have just been aliasing in the photograph, but on the newer picture it's obviously not aliasing and instead is an antenna array. On the original picture, there's also an evident backing on the radar, which suggests PESA because it's extremely large, as PESA has a magnetron or klystron unit providing the radar signals, whereas AESA only needs a relatively small computer behind it to process the incoming signals.

First, there is no evidence that Chinese has not yet mastered AESA technology, because you can found AESA on air, sea and land platforms. There aren't as many AESA radars in service in Russian military by comparison. The reality is that Russian AESA technologies are as best at parity with the Chinese, not the other way around.

Second, this picture does not conclude whether the new radar on the J-10b is AESA or PESA. There is not enough resolution to resolve any details. Your premises basing on these details are thus invalid.

As far as the Chinese mastering AESA technology goes, we know that the Chinese have AESA equipment, but it's not mastered to the point where it would be economical to place on a fighter. Like I've said before, we had reports that Chinese AESA manufacturing is 12 times more expensive than American AESA manufacturing per module, meaning that it's not economical to place on a fighter aircraft, but it IS economical to place on AWACs and ships, as the percentage of additional cost is far lower than it would be on a cheap F-16 equivalent.

APG-77 is also at least 7-10 years behind the latest technologies, because it was in serial production beginning in 1999. By your own logic, if China latest semi-conductor technologies are 7-10 years behind the latest in the West, then China today is fully capable of serial production of AESA radars for fighters. In any case, contrary to popular beliefs, latest technologies have little relevance to that what already produced.

That's true, but Chinese civilian technology tends to be more advanced than Chinese military technology, which is the opposite of the Western case where the military leads the civilian in technology. This is because the Chinese are good at getting civilian technology transfers from the West, whereas there's an arms embargo on China from the West, so China needs to buy weapons from Russia. If we follow the timeframe logic without modification, the J-10 should be as effective as a F-22 as there's only 7 years difference.

So are you arguing China does not have the capability of producing AESA radar for fighters or are you arguing it is not economical to put an AESA onto the J-10? It seems like you are doing a grape shot here... just throwing out incoherent arguments hoping one sticks.

I mean exactly what I said. If you didn't misread my post, you wouldn't have this problem. An economical AESA is needed by Chinese fighter aircraft, but just a plain old AESA is sufficient for AWACs and ships.

 

[Engineer]

No, the 32nm is slated for 2013. Among Chinese technological achievements, I picked SMIC because it's a relative disappointment. Still, and always, 7 years behind the West.

It has been more than 7 years since the production version of F-22 was delivered, and so APG-77 was in serial production for just as long. If China is 7 years behind the West in latest semi-conductor technologies, then it is certainly capable of producing an AESA just as good as APG-77 today.

Hendrik, you're right about Chinese radar on the J-10, but the Chinese radar on the J-10 is PD, not even PESA. It still fits the trend of being antiquated compared to current Russian offerings.

Russian radar produced more than a decade ago are always antiquate in comparison to what China is about to put on its latest fighters. That's the trend I see.

Siegecrossbow: this is what I mean by SDF being overly optimistic about Chinese military technological advancements. Let's just all accept that J-10B in the picture uses PESA, and that in the future it may be outfitted with AESA.

There is no indication that the radar is PESA. There is no indication that Chinese's research in PESA has actually produced production models of PESA, either.

 

[Inst]

J-10A isn't equipped with WS-10A because J-10A is a production model. That is, it has already left the design table long ago. Consequently, R&D has no meaning to the plane whatsoever. And whoever said J-10 would ever get equipped with WS-10A at all?

The J-10 was originally slated to feature the WS-10 as an engine, but the engine turned out to be utterly unsuitable for a single-engined aircraft due to reliability issues. Hence, it ran the AL-31FN, and we're all waiting for the J-10B or C to start featuring the WS-10 or a derivative to liberate it from Russian engine dependency.

Why would China come up with PESA if they already have AESA technologies?

Because PESA is less challenging to develop and is cheaper for the same application. As I've mentioned before, China is known to be able to produce expensive AESA radars, but it cannot produce cheap AESA as of yet. There's no specific reason, I'm just saying that from the image, because of the apparent antennas, the radar is a PESA, not an AESA.

 

[Engineer]

Engineer, to your statement regarding the antenna shadows, go look back at the pictures of PESA someone else posted. There were antenna on the PESA, among the receiver modules. AESA doesn't need visible antenna, because each module is both transmit and receive.

There is nothing on the PESA:

There is no requirement for PESA to have additional antennas outside of the array, either. Appearance simply isn't a valid argument to make conclusion as to whether J-10b's radar is AESA or PESA.

plawolf, read what I posted. I said it was PESA because the modules were smaller than AESA antenna, which could result in aliasing, resulting in the horizontal line. Modern PESA has much smaller modules than AESA since PESA modules only have to receive, not transmit. On the picture shown there, you couldn't see the row evident there, it could have just been aliasing in the photograph, but on the newer picture it's obviously not aliasing and instead is an antenna array.

Aliasing occurs whenever the sampling resolution is not at least twice as high the data being sampled. Aliasing has nothing to do with whether individual module is active or passive. The picture was taken from a distance. Assuming there are at least 1000 modules, regardless of being active or passive, each would fall into less than one pixel thus produce aliasing effect regardless. Your argument that the radar is PESA based on aliasing is thus invalid.

On the original picture, there's also an evident backing on the radar, which suggests PESA because it's extremely large, as PESA has a magnetron or klystron unit providing the radar signals, whereas AESA only needs a relatively small computer behind it to process the incoming signals.

APG-77 has a backing:

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APG-78 has an even bigger backing:

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As far as the Chinese mastering AESA technology goes, we know that the Chinese have AESA equipment, but it's not mastered to the point where it would be economical to place on a fighter. Like I've said before, we had reports that Chinese AESA manufacturing is 12 times more expensive than American AESA manufacturing per module, meaning that it's not economical to place on a fighter aircraft, but it IS economical to place on AWACs and ships, as the percentage of additional cost is far lower than it would be on a cheap F-16 equivalent.

There is no indication of the manufacturing cost per element in a Chinese AESA radar, thus one cannot draw any premises regarding Chinese radars are economical, which in turns mean you cannot make any conclusion based on cost.

That's true, but Chinese civilian technology tends to be more advanced than Chinese military technology, which is the opposite of the Western case where the military leads the civilian in technology. This is because the Chinese are good at getting civilian technology transfers from the West, whereas there's an arms embargo on China from the West, so China needs to buy weapons from Russia.

Civilian technologies in the West is also ahead of military technologies, prime examples are Information Technologies, Cellular Networks. This is the reason why military focus more and more on off-the-shelf components when it comes to procurement. However, it is irrelevant whether civilian technology is ahead or military technology is ahead, because at the end of the day, the best will be put into military components. We can thus only judge the newest R&D by looking at the latest technologies.

If we follow the timeframe logic without modification, the J-10 should be as effective as a F-22 as there's only 7 years difference.

Thus technological capability and time is nonlinear, which precludes one from drawing any conclusion on today's capabilities based on capabilities a decade ago. In other words, your premises that China's semi-conductor technologies are behind the West has no relevance in the discussion.

I mean exactly what I said. If you didn't misread my post, you wouldn't have this problem. An economical AESA is needed by Chinese fighter aircraft, but just a plain old AESA is sufficient for AWACs and ships.

No. If you actually have a coherent argument as to why the radar is PESA, then you wouldn't get called out for it.

 

[Engineer]

The J-10 was originally slated to feature the WS-10 as an engine, but the engine turned out to be utterly unsuitable for a single-engined aircraft due to reliability issues.

The decision to switch to Russian engine was made because WS-10 was not available back then, not because WS-10 is unreliable because there is no such thing as WS-10 to gauge reliability back then.

Hence, it ran the AL-31FN, and we're all waiting for the J-10B or C to start featuring the WS-10 or a derivative to liberate it from Russian engine dependency.

Again, whoever said J-10 will ever be fitted with WS-10 series of engines?

Because PESA is less challenging to develop and is cheaper for the same application. As I've mentioned before, China is known to be able to produce expensive AESA radars, but it cannot produce cheap AESA as of yet.

Again, China already has AESA, so your first premises (regarding challenge) is not applicable. As for your second premises (regarding costs), there is no evidence which allows you to conclude it is cost-prohibit for China to produce AESA radars for fighters.

There's no specific reason, I'm just saying that from the image, because of the apparent antennas, the radar is a PESA, not an AESA.

The extra row of unknowns do not present on PESA either, thus by your own inference the new radar cannot be PESA.