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Su33KUB

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Zhuhai air demo is nothing spectacular in terms of stunts in the air. The J-20 is just for attraction to those never seen the J-20 with own eyes. Military expo is just for customers to browse for suitable weapons or just sight seeing
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 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
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.
 
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DJ_Viper

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Modern TVC on high speed fighters is not meant for improving agility for dogfights, which was discovered by Russian researchers in Soviet era as it will bleed a lot of energy and make the aircraft a sitting duck. However they also stated that it will help pilots conduct manoeuvre more freely as TVC can come to the rescue whenever the aircraft enters stall if ongoing manoeuvre goes wrong.

F-22 and Su-57 use TVC mainly for maintaining good pitch controllability for supersonic flight and therefore the aircraft can obtain sufficient supersonic manoeuvrability. I don't really know about the rationale behind Su-30MKI using TVC anyway.
TVC is great for the 5th gen fighters, if they ever have to come down to WVR / close in fights, it helps the fighter maneuver very quickly and point to enemy's 6 at all times as it's turn would be instantaneous. While, a non-TVC fighter will have to do a full turn within 16-20 seconds. A kill is almost guaranteed with HOBS missiles.
 

Deino

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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 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
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.

Can you please stop with these stupid analysis? They are all based on the premise that they are showing the full capabilities, which is plain wrong.

The Chinese have no intention to reveal any notable true capabilities, there is no intention for chest-bumping with hyper-fancy manoeuvres like the Russian's do at MAKS.

All you can deduct from this display is the PLAAF political will to show it to the public and as such it's confidence in the WS-10C.

Anything else like turn-radius, speed of climb, thrust to weight ratio, manoeuvrability and whatever MUST be WRONG, since - in Germany we would say: "Der Pilot is mit angezogener Handbremse geflogen!" - this was just to show the J-20 flying, and not to impress the audience or any armchair analyst!

So please stop it.
 

White and Green with M/S

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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

View attachment 785091

See the lift has a bank angle effective lift

View attachment 785094
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

View attachment 785095

The Max G will be equal to the max turn rate

View attachment 785096

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

View attachment 785097
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
View attachment 785098

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 bank angle of 82 deg means G loads near 9Gs, thus it means the J-20 is close to the corner speed, basically if you look at that video there is a high bank angle
see the video

View attachment 785099

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.

Ask any engineer in Germany about the bank angle and G forces and corner velocities all will agree with me, Math is the true language.


The lift equation states that lift L is equal to the lift coefficient Cl times the density r times half of the velocity V squared times the wing area A. For given air conditions, shape, and inclination of the object, we have to determine a value for Cl to determine the lift.
The Lift Equation
https://www.grc.nasa.gov › www › airplane › lifteq



Consider it is flying at sea level J-20 thus the air density is high but since it has a low aspect ratio the lift coefficient is not as high as a unpowered glider at the same given speed since the high aspect ratio has lower drag due to vortices otherwise known to induced lift drag..
He is talking about your stupid analysis of getting SU57 for PLAN
 
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Deino

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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.
…...
I‘m not disregarding math, but you are overhyping a demonstration as the corner-stones of the J-20‘s aerodynamic capabilities in order to analyse its flight performances.

If I crawl on all four arms and legs across a street, you have nothing to calculate my top speed from. And that‚s exactly what the J-20A did at Zhuhai … it was crawling tru the sky and in now way demonstrated its true capabilities. As such, any conclusion event with math MUST be wrong.

And again: Just take this as a warning: Stop with this non-sense … we had this stupid discussion already so often under different names and you have been banned for the same BS from several forums. Therefore if you don‘t want the same fate again … stop it!
 

kungfugymnast

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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 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
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.
Great info. Basically, any aircraft with 30,000lb max thrust engine could easily take off from carrier. Su-57, F-22, J-20 can be fitted with strengthened landing gear, no issue. It is the landing approach part that matters most, as they would approach too fast due to their design. Aircraft such as F/A-18E, Rafale, J-10C, FC-31, F-35 however are designed for low speed maneuverability & stability allowing them to approach slower and land safe.

F-14B+ swingwings would extend forward being less aerodynamic to gain more lift, better control & slower approach. F-14B+ internal fuel tank max 15,000lb fuel while F-22 max fuel 18,000lb. F-14B+ vs J-20 in terms of maneuverability, the J-20 would win because of better lift from larger wing area. F-14 could hardly get 9G and known of pulling mostly 7G. An F-15C could easily out turn the F-14 in dogfight. F-22 and J-20 have higher max takeoff weight 80,000lb mainly from larger fuel tank 18,000-22,000lb and heavier armament payload >18,000lb compared to F-14B+ max take off 74,000lb (aircraft weight 34,000lb + payload max 14,500,lb + internal fuel 15,000lb). Fighters with large internal fuel tank don't fill full tank unless needed to travel long range. They don't carry full payload neither depending on mission.

J-20A with WS-10C, it would fly more like an F-15E on full internal fuel + CFTs than F-14B.
He has the posting style of Gambit. Same company.
Gambit is ex-USAF pilot by the way, he posted facts and he's definitely different person.
 

White and Green with M/S

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Great info. Basically, any aircraft with 30,000lb max thrust engine could easily take off from carrier. Su-57, F-22, J-20 can be fitted with strengthened landing gear, no issue. It is the landing approach part that matters most, as they would approach too fast due to their design. Aircraft such as F/A-18E, Rafale, J-10C, FC-31, F-35 however are designed for low speed maneuverability & stability allowing them to approach slower and land safe.

F-14B+ swingwings would extend forward being less aerodynamic to gain more lift, better control & slower approach. F-14B+ internal fuel tank max 15,000lb fuel while F-22 max fuel 18,000lb. F-14B+ vs J-20 in terms of maneuverability, the J-20 would win because of better lift from larger wing area. F-14 could hardly get 9G and known of pulling mostly 7G. An F-15C could easily out turn the F-14 in dogfight. F-22 and J-20 have higher max takeoff weight 80,000lb mainly from larger fuel tank 18,000-22,000lb and heavier armament payload >18,000lb compared to F-14B+ max take off 74,000lb (aircraft weight 34,000lb + payload max 14,500,lb + internal fuel 15,000lb). Fighters with large internal fuel tank don't fill full tank unless needed to travel long range. They don't carry full payload neither depending on mission.

J-20A with WS-10C, it would fly more like an F-15E on full internal fuel + CFTs than F-14B.
your all terminologies are false, you only trying say WING AREA, that's shows your expertise in this field, And j10/FC31, specially FC31 still not have wing area to land on Carrier and forget about J20/F22
 

kungfugymnast

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your all terminologies are false, you only trying say WING AREA, that's shows your expertise in this field, And j10/FC31, specially FC31 still not have wing area to land on Carrier and forget about J20/F22
That's not your expertise neither since you don't have certs in aeronautics engineering. Everyone here only took general aeronautical physics knowledge to post

Do you know that US General Dynamics had landed F-16N (navalized variant F-16) on carrier deck before? A-7 Corsair 2, F-8 Crusader are single engine aircraft that used to operate from USS Saratoga, USS Kitty Hawk.

J-10C wing area + fuselage bottom surface area are good enough to land on carrier with slower approach speed than J-15. FC-31 copied design cue from F-35 to get similar RCS and aerodynamic, you think it can't land on carrier better than J-15?

Whereas, J-20A & F-22 can't because they would approach the carrier too fast.
 

Su33KUB

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Great info. Basically, any aircraft with 30,000lb max thrust engine could easily take off from carrier. Su-57, F-22, J-20 can be fitted with strengthened landing gear, no issue. It is the landing approach part that matters most, as they would approach too fast due to their design. Aircraft such as F/A-18E, Rafale, J-10C, FC-31, F-35 however are designed for low speed maneuverability & stability allowing them to approach slower and land safe.

F-14B+ swingwings would extend forward being less aerodynamic to gain more lift, better control & slower approach. F-14B+ internal fuel tank max 15,000lb fuel while F-22 max fuel 18,000lb. F-14B+ vs J-20 in terms of maneuverability, the J-20 would win because of better lift from larger wing area. F-14 could hardly get 9G and known of pulling mostly 7G. An F-15C could easily out turn the F-14 in dogfight. F-22 and J-20 have higher max takeoff weight 80,000lb mainly from larger fuel tank 18,000-22,000lb and heavier armament payload >18,000lb compared to F-14B+ max take off 74,000lb (aircraft weight 34,000lb + payload max 14,500,lb + internal fuel 15,000lb). Fighters with large internal fuel tank don't fill full tank unless needed to travel long range. They don't carry full payload neither depending on mission.

J-20A with WS-10C, it would fly more like an F-15E on full internal fuel + CFTs than F-14B.


Gambit is ex-USAF pilot by the way, he posted facts and he's definitely different person.
J-20 is still limited by TWR, So using a lighter aircraft is better for a naval fighter.

Regardless of opinion, the bank angle tells you the max G load a 82 deg of bank angle generates 9Gs and the aircraft is close to stall, at Zhuhai the J-20 showed bank angles near 80 or more.

When they get WS-15 the turn rate will improve, but now still in underpowered, taking off from an aircraft carrier still will be harder.
 

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I found a yoytube channel called mhdefence or something that show about j20 carrier version with arresting gear. Is it legit?

Is that mean that j20 will become the next csg and not j35? Or is it fake?
 

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