J-35A fighter (PLAAF) + FC-31 thread

[Gloire_bb]

Modern interceptors don't really exist because if it has bays, it can be a multi-role.

interceptors got their bays before it went mainstream, in 1950s. It by itself doesn't make them multi-role, much like the existence of pylons doesn't make other fighters multi-role.
It's actually even more fun - because all USAF fighter aircraft back then, for some time, were interceptors with bays. And they thunderously lost to USN multirole birds.
Thus, while stealth is often brought in, the only USAF air superiority fighter since the mid-1950s to not feature bays was the F-15. Stealth or not, and without any multirole capability as a determining factor.

But historically speaking, the interceptor mission means a plane with stronger air performance than the general fleet, often flown by elite units, tasked with hunting down the enemy's "best" air units. While air superiority is an aircraft that patrols airspace and escorts friendlies. Basically the distinction between Spitfires and Hurricanes.

Interceptors are primarily defensive assets, trading normal combat capability for raw specs in order to timely react to the enemy initiative.
That's why interceptors throughout history tended to lose to less impressive fighter aircraft over and over, and in general, are harder to apply. J-20 has interceptor qualities, but it is not one - and unless you want to gimp it, better not think of it this way.

You can press gang air superiority fighters into interceptors and you can use interceptors to patrol air space. But pure fighters like J-10 or F-16 are not going to provide the same performance as say F-15, which leans more towards interceptor on the fighter-interceptor spectrum (or the J-20 and F-22, which are 5th gen versions of that). Using interceptors to patrol airspace represents a wasteful use of resources.

And again.
All 3 between J-10, F-16 and F-15 have interceptor missions between others. It's ironically only J-10 that actually have it among primary ones, which sort of invalidates your whole point.
F-16 has it secondary(and is not optimized for it at all), F-15, while not optimized either, somehow almost makes it through raw power.
But it should be remembered that is was not an interceptor, it specifically killed all US interceptors(and their new programs), and even F-15 NORAD variant was never allowed to be born.

Finally, patrolling airspace is an absolutely normal job for interceptors, just loitering subtype instead of point defense ones. The main aircraft family of PLAAF - flankers - were born very specifically with it as their primary purpose.

 

[TK3600]

It is interesting that J35a sports a HUD while F35 eschew it altogether. My guess is that F35 uses the HMD for almost everything visual including HUD functions, whereas we seldom see j20 pilots wearing HMD, so HUD still needed. I wonder what reasons China has to go the traditional route for pilot plane visual interface instead of relying on advanced HMDS

Tesla vs BYD dash screen vibe, and we all know who is the winner.

 

[ACuriousPLAFan]

Belly view of the J-35A. Posted by @恒苏Actline on Weibo.

 

[Schwerter_]

Belly view of the J-35A. Posted by @恒苏Actline on Weibo.

View attachment 138485

Horizontal tail design looks possibly different to what the J-35 has?

More specifically, the J-35 (naval variant) has a pair of non-moving tail booms and the horizontal tails are attached to the outside of the tail booms. This picture of the J-35A looks like it could be that the horizontal tail and the back end of the tail booms are one single piece that pivots together, similar to what the F-35 has (pic attached)


This would align with a few online comments I’ve seen that mentions the horizontal tail design of the J-35A as well as that one paper from 601 years back that discussed something called “自平衡铰链平尾” or roughly “self-balancing hinge-type horizontal tail” (pic from paper also attached)

 

[tphuang]

We know that a J-20 and J-35 compatible stand off range cruise missile (JSM equivalent) was in the works for quite a few years back, and the fact that they are able to carry A2G weapons designed around their weapons bay geometry is also well known.

However, the specific question being asked was about the comparison of J-35 (and in turn J-20) weapons bay relative to F-35's weapons bay, and it is very much the case that the F-35's weapons bay (A and C variants specifically) have central stations whose depth is greater than that of what J-20 and in turn J-35's can offer.

Considering even F-35's central bays cannot accommodate JASSM internally, it would be silly to think J-20's bay could accommodate such a weapon (not that PLAAF has JASSM in service anyhow).


Keep in mind that any discussion around J-20's A2G payload should also reserve space in the ventral weapons bay for two BVRAAMs, considering the F-35's two central bay stations are for A2G ordnance while it retains two door mounted BVRAAMs as well.

Therefore, unless one is willing to completely send in a J-20 to conduct a strike mission without any on board BVRAAM, you will probably have to halve the width of whatever A2G weapon one has in mind that you want to speculate about, to get a more realistic estimate of how big such a weapon could be.
Alternatively, if one wants to use the full width of J-20's ventral weapons bay for a more capable A2G weapon and omitting the ability to carry BVRAAMs, then that is fine as well but it also means accepting that J-20's (and J-35's) ventral bay is not comparable to that of F-35 as F-35 can carry large A2G ordnance while also carrying two BVRAAMs.

Not really.



No. J-20's weapons bay is nowhere near as deep as F-35's central bays. J-20's bay is more like F-22's bay, possibly a little bit larger, but it lacks the depth of F-35's central bays that are designed to be able to carry weapons as large as 1t JDAMs

It is kind of interesting that outsider speculated J-20 was the strike aircraft when it first came out when PLA happened to just realized it needed a larger aircraft at the time to overcome the technology disadvantage it had through larger and more powerful radar and EW suite and more range. Now, that has turned out to be a major plus given the current issues F-35 is having with upgrading its thermal management system.
Also, by expecting to fight closer within 2IC, they did not prioritize A2G ordnance. Which again allows more space to be used for everything else.

It appears to me that J-35A would have the same advantage here. Again, its nose looks extremely outsized. Being a later design that had time for refinement, it appears to me PLA realized that it could get huge advantage here by doing making it very wide for its weight class and get all the benefits of wider nose, more space for EW suite and opening the option of spacing antennas far apart.

 

[Gloire_bb]

We know that a J-20 and J-35 compatible stand off range cruise missile (JSM equivalent) was in the works for quite a few years back, and the fact that they are able to carry A2G weapons designed around their weapons bay geometry is also well known.

However, the specific question being asked was about the comparison of J-35 (and in turn J-20) weapons bay relative to F-35's weapons bay, and it is very much the case that the F-35's weapons bay (A and C variants specifically) have central stations whose depth is greater than that of what J-20 and in turn J-35's can offer.

Considering even F-35's central bays cannot accommodate JASSM internally, it would be silly to think J-20's bay could accommodate such a weapon (not that PLAAF has JASSM in service anyhow).


Keep in mind that any discussion around J-20's A2G payload should also reserve space in the ventral weapons bay for two BVRAAMs, considering the F-35's two central bay stations are for A2G ordnance while it retains two door mounted BVRAAMs as well.

Therefore, unless one is willing to completely send in a J-20 to conduct a strike mission without any on board BVRAAM, you will probably have to halve the width of whatever A2G weapon one has in mind that you want to speculate about, to get a more realistic estimate of how big such a weapon could be.
Alternatively, if one wants to use the full width of J-20's ventral weapons bay for a more capable A2G weapon and omitting the ability to carry BVRAAMs, then that is fine as well but it also means accepting that J-20's (and J-35's) ventral bay is not comparable to that of F-35 as F-35 can carry large A2G ordnance while also carrying two BVRAAMs.

There's more to that.
While f-35 bays are very deep, they're also shorter - and it doesn't help to design good cruise missiles into them (slenderness matters a lot here).

Good examples here are JSM and SOM-J, with clearly visible trade between fuel and warhead between two: jsm flies much further, som has a meaningful warhead. A clear sign that both weapons are built to the very limit of bay capacity.

Yet a longer Russian kh-69 is significantly heavier, flies further than jsm, and carries 40% heavier warhead than SOM.
Russian bay is apparently slightly deeper than Chinese one(it isn't just size of munition, but also size of suspension point, attached to a bulkhead that can withstand the kick of high G launch), but what matters here is length, not depth.
And both Chinese and Russian bay appear to be sized for 4.2m long payloads. It's noticeably more than f-35.

 

[_killuminati_]

Nvm, it is a cooling inlet. The entrance is trapezoidal to reduce signature, something similar to the hump/device on the F-35.

I had inquired about it in the past and I don't remember the answer, maybe a cooling device for an internal component. JF-17 and F-35 also have it but always just on one side. JL-9 has something like it on the aft end, Tejas a big hole on the side of the intake, and variations of it on many other aircraft.