J-20 VERSUS F-35

Guys, those aren't optical lenses, they're MADL antennas.

This ^; the white apertures are MADL antennas, the long / rectangular apertures on the leading / trailing edges are antennas for the AN/ASQ-239 Barracuda and some of the other apertures are for satellite and VHF/UHF comms.

As for ranging:

1. The video that GTA4 linked shows all the targets on a single ring; I don't think radius = range in that display (which also isn't a native F-35 display / visor feature).

2. Ranging can be done either via multiple MADL'd F-35s (remembering that F-35s will almost never fly alone) intersecting bearings and elevations, or it can be done by using the radar or Barracuda's passive RF system. Ranging can also be done via analysis of target motion or size (though these methods are limited in their accuracy and the range at which they can be used).

As for LOAL, you don't need range data at all - it is very handy to have range data, but missiles can be told to launch along a vector, with the missile seeker scanning for the target in that direction - years ago for example a RAAF F/A-18A equipped with ASRAAMs and a JHMCS, but no form of DAS or high-end RF geolocation capability, and with no secondary support aircraft, was able to LOAL engage a target behind the aircraft's wingline / outside the ASRAAM's field of regard.

Having a 3D fix is preferable because as a missile turns around it doesn't have to scan along the length of a vector (taking valuable time when a LOAL is typically being made against a close-in high-level threat), but it's not outright required.

Here is a slide from Harris showing some the CNI apertures (comms for you guys that don't know what CNI is).



Here is the Video in question with screenshots showing where the EODAS, MADL, and various CNI antenna are (1:45 mark).









Here is a pic from someone else.



Here is an MADL Antenna



https://www.harris.com/sites/default/fi ... ionics.pdf

2. Ranging can be done either via multiple MADL'd F-35s (remembering that F-35s will almost never fly alone) intersecting bearings and elevations, or it can be done by using the radar or Barracuda's passive RF system. Ranging can also be done via analysis of target motion or size (though these methods are limited in their accuracy and the range at which they can be used).

Interesting, just like (or similar to) the Passive Sonar of a Submarine.

J20 is never claimed to have 360 deg DAS coverage. It lacks rear hemisphere coverage

The J-20's DAS or MAWS has 360 coverage:

That is not a rear hemisphere coverage.

In order to measure distance, you need at least two optical devices to track the same target. But according to your photo, the rear and upper hemisphere was covered with one single optical window. That is insufficient for distance measurement and thus could not target for short range AA missile.

I also find it hard to believe that the J-20 has something that resembles DAS.

However and perhaps those sensors which supposedly cover entire area around (360º) the aircraft are something like UV sensors and as such part of a MAWS?

Isn't the physical hardware of DAS just a set of high resolution near it cameras? The real magic is in the processing of the imagery and integration with other on board sensors.

The Chinese could certainly have put in the physical hardware and the wiring. Getting it perfectly integrated with everything else will be challenging. However now a days there's a lot of commercial work on 360 image recognition and sensor fusion going on for self driving vehicle. Who knows how far the can go on a test platform if they put in a few nvidia tegra processors and star off from open source research and codes.

So far J-20 is using the traditional HUD. Is there any hint of something similar to F-35 HMDS?

So far no chiniese missiles have demonstrated any HOBS or LOAL capability.

So far no chiniese missiles have demonstrated any HOBS or LOAL capability.

There are thousands of R-73s and Python 3s in PLAAF service. That's one of the things they didn't need to copy to obtain. The license manufacture of the Python for example under the PL8 would have given the PLAAF a substantial tech transfer on offbore sight technologies. The current SR AAMs in Chinese service are claimed to have substantially higher offbore sight capability than the R-73/PL8s. E.g. PL01 has a claimed 90deg offbore sight.

Chinese anti-ship missiles have LOAL. How capable are the LOAL is another issue as that is a far more complex tech to master and integrate. I don't think the PLAAF is currently relying on that.

So far no chiniese missiles have demonstrated any HOBS or LOAL capability.

PL01 has a claimed 90deg offbore sight.

By "demonstrated" I mean "tested" not "claimed".

Everyone can claim big things. Remeber how Su-35 manufacture claimed 90 km detection range against F-22? It just got slapped over the face in Syria:

http://aviationweek.com/defense/how-f-2 ... over-syria

What's the purpose of that unique launch-rail-outside-closed-door configuration? If that is to expose the missile sensor for a while before launch, doesn't that cast doubt on the missile's Lock-On-After-Launch capability?

Chinese Fighter Developments Revealed
27 Oct 2017 Reuben F. Johnson

"...Chinese sources state that the J-20 now has a reliable domestically produced powerplant. Previous models of the J-20 were powered with the Russian-made Saturn/Lyulka AL-31F engine. The Chinese engine can still not match the performance of the Pratt & Whitney F119 that powers the Lockheed Martin F-22 Raptor, but it supposedly enables the J-20 to supercruise. There will be 100 J-20s in service by 2020 and another 100 by 2023, it is reported...."

Source: https://www.ainonline.com/aviation-news ... s-revealed

200 J-20's in service by 2023

And by then, how many F-35's will be flying? 1,500 or more?? And in the air arms of at least half a dozen US allies. Even IF the J-20 is as good as the F-35, the numbers game doesn't work in their favor. With respect to the quality issue..

* The F-35 will be stealthier (especially all aspect stealth)
* The F-35 will have far superior sensors
* The F-35 will serve in a far greater number of roles (air to air, air to ground, ISR, E/W jamming etc).
* Worldwide logistical footprint vs. mainland China only

You can argue the J-31 will attempt something similar, but then again all of the F-35 attributes I listed will still hold true. I'm not one to under-estimate the enemy, but on numbers and quality I think it's obvious - the F-35 is going to win both.

200 J-20's in service by 2023

And by then, how many F-35's will be flying? 1,500 or more?? And in the air arms of at least half a dozen US allies. Even IF the J-20 is as good as the F-35, the numbers game doesn't work in their favor. With respect to the quality issue..

* The F-35 will be stealthier (especially all aspect stealth)
* The F-35 will have far superior sensors
* The F-35 will serve in a far greater number of roles (air to air, air to ground, ISR, E/W jamming etc).
* Worldwide logistical footprint vs. mainland China only

You can argue the J-31 will attempt something similar, but then again all of the F-35 attributes I listed will still hold true. I'm not one to under-estimate the enemy, but on numbers and quality I think it's obvious - the F-35 is going to win both.

While I agree, it must also be taken in to account that the J-20 will not be spread all over the world, but most likely concentrated on specific targets closer to home. In boxing terms they basically have a decent jab, that will force the champ to stay at a distance.

While I agree, it must also be taken in to account that the J-20 will not be spread all over the world, but most likely concentrated on specific targets closer to home. In boxing terms they basically have a decent jab, that will force the champ to stay at a distance.

Here is the IIIS 2018 infographic I also posted on the Rafale thread. China is spending a lot of money on AAMs. To a large extent, China needs only to knock out US tankers, AEW and other support aircraft with these newer, longer range AAMs. The J-20 is likely sufficient to survivablly fire these newer, longer range AAMs.

Thanks for clearing that up earlier regarding PL-15/PL-XX, seems my earlier source was the one confused. The only snag is very long range non-ramjet PL-XX is not carried internally/stealthy so will require a powerful radar to track the opponent before the launching aircraft (J-16) is discovered and intercepted. Only practical against a stealthy F-35 if the tracker is a J-20 that can get close enough to spot a F-35, track it and survive the whole of the PL-XX journey time which is still unlikely. Probably a technique better suited though against non-stealthy support aircraft as shown in the diagram. The ramjet version though at around 4m could fit into a J-20 bay and make life interesting even for AIM-120D/Meteor equipped F-35s. However ramjet technology for Chinese missiles is still a WIP.

https://www.popsci.com/amp/china-new-lo ... ir-missile
http://www.chinatopix.com/articles/1144 ... romise.htm