J-20 5th Gen Fighter Thread IV (Closed to posting)

[antiterror13]

Does anyone think Chengdu will put more changes to the J-20's aerodynamic frame in later prototypes? It seems further development of avionics and materials, and the waiting period for 606's new engines seem to be their priority now.

I don't think they will change the aerodynamic frame much, its almost done. Avionic and material may get improved later on. I am not aware of 606 engine? what is that? is it further development from WS-15A?

 

[Tyloe]

oh I meant the normal ws-15 project by institute 606 of Xi'an Aero Engine corp.

 

[no_name]

They might decide to make some changes after some numbers are already in service, like how J-10B is derived from J-10A. But that will probably be considered a separate project from the current one, and not gonna happen in the near future.

 

[antiterror13]

Any idea how much is the development/program cost of J-20 and cost per unit?

Really extremely hard to believe that program cost of F-22 is US$66.7B and the unit cost is $150M ... with only less than 200 F-22 operational, it means cost per single F-22 would be close to $500M ... yes half a billion dollars!!!!!

 

[siegecrossbow]

Does anyone think Chengdu will put more changes to the J-20's aerodynamic frame in later prototypes? It seems further development of avionics and materials, and the waiting period for 606's new engines seem to be their priority now.

At a minimum they need to alter the rear-aspect and possibly the intakes to accomodate for higher-thrust engines.

 

[Franklin]

I have a question about the J-20 being underpowered. We know from photo's that the J-20 is smaller than the Flankers and it also uses more composite materials. So using the same engines as the Flankers wouldn't that give the J-20 a higher thrust to weight ratio than the Flankers which is considered to be one of the world's most agile planes.

 

[siegecrossbow]

I have a question about the J-20 being underpowered. We know from photo's that the J-20 is smaller than the Flankers and it also uses more composite materials. So using the same engines as the Flankers wouldn't that give the J-20 a higher thrust to weight ratio than the Flankers which is considered to be one of the world's most agile planes.

Two word rebuttal: internal weaponsbay.

 

[Insignius]

Two word rebuttal: internal weaponsbay.

But with less drag due to the internal weapons bay, wouldnt it make it up somehow?

 

[siegecrossbow]

But with less drag due to the internal weapons bay, wouldnt it make it up somehow?

True, but I just think that it is ludicrous for the J-20 to have a lighter empty weight than the Su-27.

 

[manqiangrexue]

True, but I just think that it is ludicrous for the J-20 to have a lighter empty weight than the Su-27.

By how much? The composite components of the air-frame should give some weight-loss. J-20 is smaller, that's more loss. The original Su-27 used old Russian avionics. How does the weight of modern avionics comparable with those? Also, the original AL-31F used to be 122kN (Su-27 being quite agile on those) while the ones on J-20 would be at least 137kN (AL-31FN3 for J-10), possibly up to 145kN, which is a 12-19% power increase. All that plus the reduced drag from internal carrying seems pretty decent to me.

But then again, the F-22 is 62 feet but is quite heavy, 21-22 tons as compared to the 18 ton Su-27SK. Although it was fashioned a long time before where it may have used less composites, that it is way heavier than the older 14-ton, 64 feet F-15 still says that stealth and modernization come at a heavy weight penalty.