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Chengdu J-20 5th Generation Aircraft News & Discussions

That's what the J-20 did, a cobra by going suddenly vertical and then push the throttle to do a sustain climb. When you are vertical, your body will slow you down quickly like a brake. That's the purpose of a Super Cobra. It's actually not very useful in air combat, because it bleeds your energy too fast and too much.




I have never seen a J-20 do a Cobra and let me reiterate what I said before, going into a vertical climb will not "slow you down quickly like a break" unless the aircraft does a Cobra maneuver which is something different altogether.
Its gravity and atmospheric conditions that will slow an aircraft down.




If your enemy catch you doing that, he could loop over you like that glider and get behind you, without losing too much energy.





The Cobra has actually been used in combat and it worked. In training exercises it also worked. The Cobra maneuver you see in air shows is not how pilots in combat would perform the Cobra. In airshows it is exaggerating and meant to awww, the crowed.





This I disagreed. A sustain vertical climb could be done, long enough to demonstrate its Trust to Weight Ratio is > 1. No need to climb to maximum altitude.

In fact, if your maximum altitude is 60,000ft, you could climb vertically far lower than that, because you are not using lifting force from the wings, your accumulated kinetic energy, to help with the climb, just your raw engine power.


You will go up like a rocket, not like an airplane, and use up a lot of fuel and reach lower altitude.



The point is that we don't know how long a J-20 can sustain a virtcall climb. Just as you were quick to point out the glider only briefly went virtically before it did a loop. We don't know how long that glider could have maintained virticall flight. What's important is that aircraft with horrible thrust to weight ratios can go into virticall climbs, even gliders with no thrust or engines can do it so people debating the thrust of the J-20 based off a brief virticall climb is pointless.
 
I have never seen a J-20 do a Cobra and let me reiterate what I said before, going into a vertical climb will not "slow you down quickly like a break" unless the aircraft does a Cobra maneuver which is something different altogether.
Its gravity and atmospheric conditions that will slow an aircraft down.










The Cobra has actually been used in combat and it worked. In training exercises it also worked. The Cobra maneuver you see in air shows is not how pilots in combat would perform the Cobra. In airshows it is exaggerating and meant to awww, the crowed.









The point is that we don't know how long a J-20 can sustain a virtcall climb. Just as you were quick to point out the glider only briefly went virtically before it did a loop. We don't know how long that glider could have maintained virticall flight. What's important is that aircraft with horrible thrust to weight ratios can go into virticall climbs, even gliders with no thrust or engines can do it so people debating the thrust of the J-20 based off a brief virticall climb is pointless.


That glider is not doing a vertical climb, its doing a loop around using its own kinetic energy.

"vertical climb will not "slow you down quickly like a brake"

Turn your plane's body vertically will act as if its a giant air brake. It will bleed your horizontal speed. If you don't push the throttle, you will slow down, and then hang in the air momentarily, and then drop.

If you push the throttle, your horizontal speed will still quickly goes to zero, but then you will start climbing vertically entirely by your engine's raw power.

If you open your car doors fully, while driving on the road, and you don't step on the gas pedal, your car will slow down quickly, so why not an airplane?

The difference between a cobra and a sustain vertical climb is that in a Cobra, the pilot is not pushing the throttle to climb. He is just using the vertical body to slow down and let the other guy fly past him.

The J-20 did a sustain vertical climb into the cloud, how long it continue to climb after we can't see it anymore, we don't know.

I want to point out that it's horizontal speed was very slow, when it started the climb, so it was not converting its horizontal speed into the vertical climb, much.

My conclusion is that it requires TWR > 1, to do a vertical climb. I can accept the demo in the airshow is not sufficiently long enough for us to conclude beyond a shadow of doubt.

But I am convinced that it doesn't need to climb all the way to maximum altitude to demonstrate its TWR is > 1.
 
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I studied Electrical Engineering in University. I worked as a software engineer with US Defense Company in all my working life in US. We make Communication, Control, Intelligence, and Command equipments for Pentagon. While I don't have a Ph.D, all my colleagues have at least a Master and Ph.D in various fields.

Well, if my upper bound is too high, please use method of estimation I have shown to come up with your own estimates.

I would love to see you and Deino and others to do the same and see what values you would come up.

Not very hard at all. You can use a calculator to do the simple math.

Asok, are you an ABC or a new immigrant from China?
 
just got an update from my source, J-20 is using WS10B variants````````and the they plan to built 600+ j-20s```
any source?
will those supposed 600+ be converted to ws-15 if it were readied? will that be cost effective than new j20 with ws-15?
 
any source?
will those supposed 600+ be converted to ws-15 if it were readied? will that be cost effective than new j20 with ws-15?
The WS-10B i believe can be transfer to J-10C once WS-15 is available.
 
any source?
will those supposed 600+ be converted to ws-15 if it were readied? will that be cost effective than new j20 with ws-15?
no source, :D`````600+ is the planned total number, doesnt have to be all WS-10 varants````he said ‘10B 很多' thats it````
 
The J-20 was never designed to be a dogfighter and doesn't even have a gun.

Here's the location of the gun port on the F-22. You can see the outline very clearly.

SqrmqLi.jpg


Where is the gun port on the J-20? We have high resolution photos now. There is no excuse for not being able to identify the gun port at this point.

aihDH8N.jpg

8bABkMI.jpg


Short-range air-to-air missiles have a minimum range. You need a gun in a dogfight. The F-4 Phantom already made the mistake of not having a gun.

mpgn0SY.jpg


Is CAC incapable of designing a gun? Does PLAAF not have a gun requirement for fighters? Of course not. J-10 has a gun.

j-10-gun.jpg
 
The J-20 was never designed to be a dogfighter and doesn't even have a gun.

Here's the location of the gun port on the F-22. You can see the outline very clearly.

SqrmqLi.jpg


Where is the gun port on the J-20? We have high resolution photos now. There is no excuse for not being able to identify the gun port at this point.

aihDH8N.jpg

8bABkMI.jpg


Short-range air-to-air missiles have a minimum range. You need a gun in a dogfight. The F-4 Phantom already made the mistake of not having a gun.

mpgn0SY.jpg


Is CAC incapable of designing a gun? Does PLAAF not have a gun requirement for fighters? Of course not. J-10 has a gun.

j-10-gun.jpg

There are two possible locations, and you can see both of them on the 2nd J-20 pic. One is at the same location as the F-22, you can see a panel of different color there. Another is right in front of the root of the left wing, you can also see a different set of panels there.
 
Can you guys tell if this is legit?

========
China to Make 500 J-20Bs with Homegrown Powerful WS-15 Vector Engines
Posted: December 26, 2016 | Author: chankaiyee2 |


Taiwan’s official Central News Agency says in its report on December 24 that China will build 500 J-20B, more than the future total number of other fifth-generation fighter jets in Asian Pacific.

In its report, the agency quotes Hong Kong military commentator Leung Kwok-leung’s December-24 article on Mingpao that speeding up the deployment of J-20s is China’s set strategic goal.

J-20B is an improved version of J-20 installed with China’s new homegrown powerful WS-15 Emei turbofans. China has already developed WS-15 all-direction vector turbofan with thrust-weight ratio of 10. The turbofan is now undergoing intensive tests and will be ready to be installed in J-20B by 2019, an improved version of J-20.

Leung’s article quotes Xu Yongling, China’s chief test pilot, as saying in the past, “China’s future principal fighter jet J-20 will be formally commissioned in 2017. The number deployed will be close to 100.”

There has recently been information from external sources that China will deploy 4 air regiments of J-20 fighter jets within a short period of time. There are 96 fighter jets in 4 regiments, close to the 100 disclosed by Xu. According to China’s production capacity, it takes less than 3 years for China to build so many J-20s.

The article says that China now has two J-20 production lines, one producing J-20 with Russian AL-31 engines and the other producing J-20A installed with China’s WS-10B Taihang engines.

Russia has developed 99M1 to 99M4 improved versions of AL-31F, but China has also developed improved versions of WS-10 WS-10A and WS-10B better than Russian ones with thrust-weight ratio of 9 than Russia’s 8 and longer life of 1,500 hours than 800 hours of the old version.

It is said that a third production line has recently gone into operation to produce J-20A. As each line makes one J-20 a month, their combined production capacity will be 36 a year.

The article discloses that by the end of 2019, there will be a fourth J-20 production line for trial production of J-20B using China’s homegrown WS-15 Emei turbofans.

Due to the use of WS-15, J-20B’s cruise speed will be Mach 1.8 and maximum speed exceeds Mach 2.2, equal to those of US F-22. China will produce 500 J-20B, more than the future total number of other fifth-generation fighter jets in Asia-Pacific.

The article points out that recently the appearance of 4 J-20s with serial numbers from 78271 to 78274 have been disclosed on the Internet. Such serial numbers are PLA air force’s numbers. All those J-20s have low visibility coating.

In addition TerraServer took a satellite photo on November 17 of two J-20s at Dingxin Air Force Base in Jiuquan City, Gansu Province. The J-20s were obviously taking part in the annual large-scale “Red Sword” combined drill in November. The drill is the largest-scale real war air force combined drill so far in the world. The photo proves that J-20 will soon be deployed for real war.

Source: taiwan.huanqiu.com “Taiwan media: Mainland will build 500 J-20Bs exceeding the total number of fifth-generation fighter jets in Asia-Pacific” (summary by Chan Kai Yee based on the report in Chinese)
 
Can you guys tell if this is legit?

========
China to Make 500 J-20Bs with Homegrown Powerful WS-15 Vector Engines
Posted: December 26, 2016 | Author: chankaiyee2 |


Taiwan’s official Central News Agency says in its report on December 24 that China will build 500 J-20B, more than the future total number of other fifth-generation fighter jets in Asian Pacific.

In its report, the agency quotes Hong Kong military commentator Leung Kwok-leung’s December-24 article on Mingpao that speeding up the deployment of J-20s is China’s set strategic goal.

J-20B is an improved version of J-20 installed with China’s new homegrown powerful WS-15 Emei turbofans. China has already developed WS-15 all-direction vector turbofan with thrust-weight ratio of 10. The turbofan is now undergoing intensive tests and will be ready to be installed in J-20B by 2019, an improved version of J-20.

Leung’s article quotes Xu Yongling, China’s chief test pilot, as saying in the past, “China’s future principal fighter jet J-20 will be formally commissioned in 2017. The number deployed will be close to 100.”

There has recently been information from external sources that China will deploy 4 air regiments of J-20 fighter jets within a short period of time. There are 96 fighter jets in 4 regiments, close to the 100 disclosed by Xu. According to China’s production capacity, it takes less than 3 years for China to build so many J-20s.

The article says that China now has two J-20 production lines, one producing J-20 with Russian AL-31 engines and the other producing J-20A installed with China’s WS-10B Taihang engines.

Russia has developed 99M1 to 99M4 improved versions of AL-31F, but China has also developed improved versions of WS-10 WS-10A and WS-10B better than Russian ones with thrust-weight ratio of 9 than Russia’s 8 and longer life of 1,500 hours than 800 hours of the old version.

It is said that a third production line has recently gone into operation to produce J-20A. As each line makes one J-20 a month, their combined production capacity will be 36 a year.

The article discloses that by the end of 2019, there will be a fourth J-20 production line for trial production of J-20B using China’s homegrown WS-15 Emei turbofans.

Due to the use of WS-15, J-20B’s cruise speed will be Mach 1.8 and maximum speed exceeds Mach 2.2, equal to those of US F-22. China will produce 500 J-20B, more than the future total number of other fifth-generation fighter jets in Asia-Pacific.

The article points out that recently the appearance of 4 J-20s with serial numbers from 78271 to 78274 have been disclosed on the Internet. Such serial numbers are PLA air force’s numbers. All those J-20s have low visibility coating.

In addition TerraServer took a satellite photo on November 17 of two J-20s at Dingxin Air Force Base in Jiuquan City, Gansu Province. The J-20s were obviously taking part in the annual large-scale “Red Sword” combined drill in November. The drill is the largest-scale real war air force combined drill so far in the world. The photo proves that J-20 will soon be deployed for real war.

Source: taiwan.huanqiu.com “Taiwan media: Mainland will build 500 J-20Bs exceeding the total number of fifth-generation fighter jets in Asia-Pacific” (summary by Chan Kai Yee based on the report in Chinese)
.
When first read it, it didn't sound legit. Just too good to be true!

This Chan kai yee article is not very reliable. Usually Taiwanese source has lots of BS.
Thanks for your confirmation.
 

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