J20 Stealth Fighter

vishnugupt

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J-20 looks good but its flying characteristics are no better than Boeing 878 dreamliner. it visibly looks very heavy and lazy perhaps due to underpower engines. Seriously, one can imagine how maneuverable a fully loaded J-20 would be.

Maybe, Chinese took the American principle very seriously .... Fly straight, look first, Shoot first and run first.
 

MiG-29SMT

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J-20 looks good but its flying characteristics are no better than Boeing 878 dreamliner. it visibly looks very heavy and lazy perhaps due to underpower engines. Seriously, one can imagine how maneuverable a fully loaded J-20 would be.

Maybe, Chinese took the American principle very seriously .... Fly straight, look first, Shoot first and run first.
All stealth aircraft have highly compromised aerodynamics see:

See this stealth derivative of MiG 1.42

1633778588898.png


The original pure aerodynamic machine

1633778760692.png


Canards are above wing level, ventral fins have almost no canting, J-20 without TVC nozzles and WS-15 is not that a good performer.

Eurofighter is also a good performer

1633779154218.png
 

Yodello

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The J20 is such a beautiful Plane, and it looks quite menacing at the same time.
Despite what the naysayers say, the J20 gives the PLAAF the edge over all other Air Forces outside of the US Military, it also gives a chance to balance the Airpower against the US Military. Newer iterations, with incremental improvements, will make it even more powerful within half a decade.

Putting together the J20, along with the J16, J16D and the J10B and J10C, and also with the CATOBAR J15, the PLA Airpower is taking a monumental leap.
I believe that with the J16, the PLA has overtaken even the US in conventional Fighters.
All that is needed is to built the J20 in greater numbers, to achieve parity in stealth fighters

It is truly staggering, the level of qualitative and quantitative leap that China has taken in its Airpower.
Many of my fellow countrymen simply cannot come to grasp, or simply refuse to believe, the sheer power and capability of the PLA Airpower. Even more astonishing and sobering is the fact that these are all indigenous, all built in-house.

We seriously need to take a cold hard look in the mirror. We need to start pouring real money into R&D, and push strongly and consistently for acquiring knowhow to help in indigenization of critical Military assets
 
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MiG-29SMT

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The J20 is such a beautiful Plane, and it looks quite menacing at the same time.
Despite what the naysayers say, the J20 gives the PLAAF the edge over all other Air Forces outside of the US Military, it also gives a chance to balance the Airpower against the US Military. Newer iterations, with incremental improvements, will make it even more powerful within half a decade.

Putting together the J20, along with the J16, J16D and the J10B and J10C, and also with the CATOBAR J15, the PLA Airpower is taking a monumental leap.
I believe that with the J16, the PLA has overtaken even the US in conventional Fighters.
All that is needed is to built the J20 in greater numbers, to achieve parity in stealth fighters

It is truly staggering, the level of qualitative and quantitative leap that China has taken in its Airpower.
Many of my fellow countrymen simply cannot come to grasp, or simply refuse to believe, the sheer power and capability of the PLA Airpower. Even more astonishing and sobering is the fact that these are all indigenous, all built in-house.

We seriously need to take a cold hard look in the mirror. We need to start pouring real money into R&D, and push strongly and consistently for acquiring knowhow to help in indigenization of critical Military assets
The Zhuhai air displays tells a lot about J-20 performance and specifications.

First since it lacks thrust vectoring nozzles it had no post stall capability, but it also tell another fact, have you seen models of Su-57 on board of potential russian aircraft carriers? well Su-57 has a very short take off run, so they can navalize it.

Why then J-31 will be used for a carrier version? everything is weight, even with catapults a lighter aircraft will be more capable to take off with a higher fuel and weapons load.

See that the flight display only shows some vertical loops and horizontal turns and rolls, pretty very basic maneouvres, no post stall, no post stall means faster speeds to keep the minimun lift it needs to do not stall and fall from the sky.

So it means in order to keep safety for the expectators you need higher speeds.

So basically the display is the highest turns at the safest speeds, the turn you quoted and our friend says 60 deg/s starts at 20 second and ends at 40 seconds, so that is a 18 deg/sec turn rate.

Now why they are making such very tight turn? because that is a tight turn it is comparable to an F-14 turning.

See that F-14 was an 18190kg tonnes aircraft at empty weight, pretty much the minimun weight J-20 could achieve, since most aerospace materials are carbon, aluminium, steel and titanium, regardless of additive technologies 3D printing or composite materials


However see F-22 has a Max take off of 38000 kg, 6 tonnes more than an F-14
F-22 Raptor
The F-22 Raptor is the Air Force
www.af.mil
Now consider fuel weight, since fuel basically is kerosene it is basically hydrogen and carbon, so fuel in J-20 or F-22 is the same (The formula of kerosene is C12H26−C15H32. )


What does it say? well that Su-57, J-20 or F-22 weight range does not change that much due to aerospace materials and fuel.

So if WS-10 has lower yield thrust, the flight display shows the limitation due to weight and thrust J-20 has now.

See that best turns are achieved at sea level any aircraft manual says that due to higher air density, so you are seeing J-20 at its best.

Since WS-10 also uses Kerosene based fuel lower yield thrust means to achieve higher speeds with a lower yield engine means more weight in fuel.

So you can calculate J-20 very likely has a max take off weight of 38000kgs too specially since WS-10 are less capable than F119 engines or type 30 engines thus shows a more conservative and less impressive flight display than F-22 or Su-57.
 

asianobserve

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asianobserve

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The J20 is such a beautiful Plane, and it looks quite menacing at the same time.
Despite what the naysayers say, the J20 gives the PLAAF the edge over all other Air Forces outside of the US Military, it also gives a chance to balance the Airpower against the US Military. Newer iterations, with incremental improvements, will make it even more powerful within half a decade.

Putting together the J20, along with the J16, J16D and the J10B and J10C, and also with the CATOBAR J15, the PLA Airpower is taking a monumental leap.
I believe that with the J16, the PLA has overtaken even the US in conventional Fighters.
All that is needed is to built the J20 in greater numbers, to achieve parity in stealth fighters

It is truly staggering, the level of qualitative and quantitative leap that China has taken in its Airpower.
Many of my fellow countrymen simply cannot come to grasp, or simply refuse to believe, the sheer power and capability of the PLA Airpower. Even more astonishing and sobering is the fact that these are all indigenous, all built in-house.

We seriously need to take a cold hard look in the mirror. We need to start pouring real money into R&D, and push strongly and consistently for acquiring knowhow to help in indigenization of critical Military assets

Thanks to Russia, the favorite Uncle of a lot of members here...
 

MiG-29SMT

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I do not need German for this analysis, but Math, that you have disregarded, something any engineer will not do, can you know things by the display? yes with Math yes.

Any one who knows basic aerodynamics knows the importance of trigonometry to deduce lift, banking angle, corner speed, turn rate and turn radius, in fact you are completly wrong the banking angle gives you the G load force, the G load for gives you the corner speed which is defined by the max turn ability.

Simple graphs and formulas gives you a basic way to analyse the video.

First let us go by Lift and Bank angle
1634248503348.png


See the lift has a bank angle effective lift

1634248519416.png

Consider the Max lift coefficien limit is corner speed, which is basically the highest turn rate at the lowest speed, at the max G load
1634248697696.png


The Max G will be equal to the max turn rate
1634248566691.png



the Tangent is very important because it will help to see the lift weight vector, and it is used to calculate the turn rate and turn radius
1634248585774.png

you can see therefore that if you look at J-20 banking angle you can really see how many Gs are applied on the aircraft thus how close is to stall and Max instantaneous turn rate

1634248598328.png

What you have disregarded is the bank angle is telling you the stall speed too,

So I will put it simple, the Bank angle the J-20 is executing is telling you a lot of things given the speed, at a higher speed a bank angle og 82 deg means G loads near 9Gs, thus it means the is close to the corner speed, basically if you look at that video there is a high bank angle
see the video

1634248652246.png

so regardles your opinion I am wrong, the bank angle shows a near 90 degrees one, J-20 is turning at its best there because the G loads are near 9 or 9G
 

MiG-29SMT

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a bank angle in a turn close to 80 degs means 9Gs, it means corner speed.

Can I say the exact Turn rate of J-20? no of course not, but by looking at that bank we can see it is turning tight, and is a better aproximation by method than just saying "we can not know".


https://**********/pdf/attachments/1634362697295-png.785446/


And I have used known data easy to use, that turn on the picture shows a close to 90 degree bank, that approximation by bank angles is a much better method to guess the real capabilities by using physics,. but the reality the bank angle method is a scientific approximation since it is a fact that bank angles tell you the G load, the G load of 9Gs tell you the aircraft is about to stall so it is close to max instataneous turn rate.
 

MiG-29SMT

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To make a maximum rate turn, you need to turn at the highest angle of bank that can be sustained at the lowest possible airspeed – just above VS – that is why the stall warning is used to indicate maximum rate.

Maximum rate turns | aviation.govt.nz


1634375969907.png

In the aforementioned videos J-20 is flying at sea level which is the highest density thus it can generate the most of lift and the aircraft is flying with a very high angle of attack.

Thus the J-20 is showing low speed high bank angles at low altitude so basically you are seeing turning at its best see the engine factor

to turn at maximum rate we need maximum centripetal force and maximum lift. The increased angle of attack means increased drag, so full power is used. As rate of turn is proportional to velocity, the limiting factor in a maximum rate turn is power.
Maximum rate turns | aviation.govt.nz


What I am saying is by the low speed and high bank angles you know it is turning at its best or close to it, but still the J-20 is not turning very well the result of still not having WS-15


Now 18 deg/sec is like a F-18 Hornet, so J-20 now very likely can keep up with the Hornet.
 

J20!

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To Beihan University:

"FBOC (Finishing-machining of the Bonding_points between oversized components)"( it is just a rough translation,because it is a quite abstract tech term) is a quite key tech to the R&D of aircrafts. To solve the finish-machining of the bonding-pointing between the airframe and wings of "the most important aircraft project" , the tech team led by Professor Zhang Deyuan from Beihan Univ. spent only less than 1 year in finishing the development of the tech. The tech has been applied to the R&D of "the most important aircraft project" and helped the project much.

the tech team of Beihan University cooperated quite smoothly with us and finished the tech integration on May 20th, 2010.Then, the team went on working hard all day and all night in shifts for the coming over 40 days and finished all tests of parameters-setting. On Octo 14th,2010, the tech team had finished assembling the airframe and wings of the two prototypes(01 and 02).

Latest news:

a reported CHinese 5G bird
The long rumored Twin Seat J20 seems close to breaking cover. The characteristically blurry pics trending online seem legit, but...

IMG_20211026_104653.jpg

IMG_20211026_104659.jpg


 

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