J-XY - maybe J-35 - next generation carrier-borne fighter


Blitzo

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Here is one source, I link it here without supporting the claims of the youtuber. If you understand Cantonese, you can follow along.


The main points he was making,

1. J35 has an empty weight of 11.5 tons, much lower than F-35 empty weight of 15.7 tons.
2. Dual WS-19 provides 22 tons of thrust, higher than F-35 19.5 tons.
This means a higher payload and higher supercruise for the J-35 (he estimates Mach1.3)
3. Using two smaller diameter engines compared to one large one has advantages. He compared F-22 and F-35 and determined that F-22, due to its dual engines, has more reserves and can have a higher acceleration compared to F-35.
4. This is not from the guy, but I did read somewhere the by-pass ratio of a large engine like the F-35 is higher than the J-35. For fighter jets, the lower the by-pass, the higher performance in high speed super sonic region. No?

Well, his claims are overly simplistic.
For the purposes of general discussion, I'll examine those points and explain why comparing the J-XY/35 to F-35 is not a good exercise.
I will also move these posts to a different thread.

1. Empty weight in isolation is not useful. Loaded weight and maximum take off weight (as well as internal fuel load) are all equally as important.
2. Again, that depends on what the loaded/operational weight of the two aircraft are during a normal mission. Furthermore, two medium thrust engines versus one heavy thrust engine places different consequences for things like airframe configuration options (and also weapons bay geometry options), as well as full consumption.
3. The kinematic performance difference between F-22 and F-35 cannot be deduced as one being twin engined and one be single engined.
4. There are also benefits in thrust, fuel burn and thus range. The standard F-35A has a combat radius that is very close to the F-22, due to a combination of factors, one of which is the F135 engine, but also because the F-35A was designed with substantial internal fuel volume.


The J-35 has a flatter and smoother exterior, better for stealth and drag.

On paper yes.
But in practice, a more stocky fuselage enables larger weapons bay dimensions and greater internal fuel than what may otherwise be possible.
And modern RAM enables even semi-bulbous exteriors to still achieve a VLO RCS.


He cited encounters between J-20 and F-35 where the J-20 was able to sneak up to the F-35 unnoticed even by the EOTS of the F-35, and infer that there is infrared stealth built into the J-20 which are not in the F-35. He speculated that the J-35 will have the same infrared stealth and be less detectable compared to the F-35.

We have no credible indications to suggest that "J-20 was able to sneak up on F-35 without being noticed by F-35". It's absolute fantasy to believe we would have access to such information in the public domain.


In short, the guy should be ignored, and he is over simplistic.

I personally think it would be better if the J-XY/35 are not compared with F-35 at all, and it is far too early to even talk about how capable J-XY/35 is relative to F-35 beyond "both are 5th generation medium weight fighter aircraft".

However, they are different aircraft designed with different requirements in mind, and more importantly being procured at different scale and in different strategic contexts to one another.
A direct one to one comparison of "specifications" is at best useless, at worst disastrously misleading.



There are many people who make youtube videos and who write blog posts.
Don't believe everyone, and if it is someone that doesn't have established credibility, it is important to first thoroughly explain why they are worth listening to, to begin with.
 

Blitzo

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I am not saying the claims made by this guy is credible. It is the reason I ask @tphuang the question of if J-35 is a better plane compared to F-35C. @Blitzo ask for sources and I provided my source.

Your answer is -- J-XY/35 and F-35C shouldn't be compared at all, and anyone trying to give an answer is overreaching.

It is better to not even ask the question to begin with.
 

Scchwerter_

Junior Member
Registered Member
Here is one source, I link it here without supporting the claims of the youtuber. If you understand Cantonese, you can follow along.


The main points he was making,

1. J35 has an empty weight of 11.5 tons, much lower than F-35 empty weight of 15.7 tons.
2. Dual WS-19 provides 22 tons of thrust, higher than F-35 19.5 tons.
This means a higher payload and higher supercruise for the J-35 (he estimates Mach1.3)
3. Using two smaller diameter engines compared to one large one has advantages. He compared F-22 and F-35 and determined that F-22, due to its dual engines, has more reserves and can have a higher acceleration compared to F-35.
4. This is not from the guy, but I did read somewhere the by-pass ratio of a large engine like the F-35 is higher than the J-35. For fighter jets, the lower the by-pass, the higher performance in high speed super sonic region. No?
The J-35 has a flatter and smoother exterior, better for stealth and drag.
He cited encounters between J-20 and F-35 where the J-20 was able to sneak up to the F-35 unnoticed even by the EOTS of the F-35, and infer that there is infrared stealth built into the J-20 which are not in the F-35. He speculated that the J-35 will have the same infrared stealth and be less detectable compared to the F-35.
11.5t empty weight is nigh impossible for a jet that size, keep in mind that the FC-31 1.0 (a jet smaller in size and not navalized) has a claimed empty weight of 12.5t, I just don't see SAC able to shed off a full ton on top of everything they did.
 

Gloire_bb

Senior Member
Registered Member
Your answer is -- J-XY/35 and F-35C shouldn't be compared at all, and anyone trying to give an answer is overreaching.
it's perfectly right to compare them - both are aircraft of exactly the same role and class, same era, and with a reasonable chance of fighting each other - thus making it both valid and valuable.

It's just too early to really say much thou - especially for non-specialists discussing doubtful numbers.
 

Blitzo

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it's perfectly right to compare them - both are aircraft of exactly the same role and class, same era, and with a reasonable chance of fighting each other - thus making it both valid and valuable.

It's just too early to really say much thou - especially for non-specialists discussing doubtful numbers.

Too much nuance.
"No, stop" is what I am trying to distil my point down to.

Introducing too much justification for why it might theoretically be reasonable to compare the two, ends up incentivizing people to think that it is constructive to talk about it.
 

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