J-20... The New Generation Fighter III

[escobar]

They Came Here More For The Pride:

so many girls interested in a military aircraft

 

[AssassinsMace]

Is this site being attacked by the pride police? Got kicked out twice while trying to posts these pics and then it took forever to get back here.

A lot of nice photos today and this isn't all of it.

---------- Post added at 02:20 PM ---------- Previous post was at 01:48 PM ----------

Here's a video. Nothing spectacular but probably one of the clearest fly-bys so far. You also see a little canard action.

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Pardon, didn't see the video was posted already.

 

[plawolf]

I love these shots as they give you a very clear view of what the canards are doing at different stages during a turn.

Hopefully, someone would have some HQ pics of this same sequence, so maybe we can also get a closer look at what all the other control surfaces are doing.

I would also like a closer view at those lines they have put on the left wing at least. You can see them quite clearly on the 4th and 9th images.

 

[Engineer]

Lower trim drag, means better acceleration and top speed characteristics, so any thrust vectoring system will increase that on J-20.

False. Lower trim drag does not automatically equate to better acceleration and top speed characteristics, since the reduction in trim drag is negated by loss in propulsive force by having to point thrust at direction other than the aft pointing vector.

From a Nasa paper:

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:

When utilizing thrust vectoring to reduce trim drag, some means of accounting for the decrease in the
available propulsive force needs to be included. This thrust loss arises from the diversion of propulsive thrust
to generate a trim force.

In other words, aerodynamic surfaces and thrust vectoring both converts forward energy into side-way energy. They just do it via different methods. Installing TVC doesn't magically add benefits as the way you have described; it doesn't conform to Laws of Physics. If a benefit is negate by a penalty then the sum is zero and you can't call that a net benefit.

The other problem presented by moving aerodynamic surfaces is higher RCS, so adding TVC nozzles will reduce that RCS, thus TVC nozzles will benefit J-20 stealth characteristics as this article let us see
An all-moving canard capable of a significant nose-down deflection will protect against pitch-up. Control canards have poor stealth characteristics, because they present large moving surfaces forward of the wing

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Stealth only matters at cruise. When significant movement is required from the canards to the point of affecting stealth characteristics, it means the aircraft is already engaging in dog fight where RCS is meaningless.

 

[AssassinsMace]

They Came Here More For The Pride:

Not sure of the translation but in one post I read the number of people seen hanging around to take pics have grown by "20." People, per cent, or times?

 

[Engineer]

Squeezing the exhaust through a flat, narrow nozzle produces a mixed plume with a large surface area, which cools quickly. Airframe radiation — whether caused by solar or friction heating — can be reduced with the use of infrared suppressing paints and coating

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This is related to nozzle shape, and has nothing to do with TVC.

Thurst vectoring nozzles reduce drag that in turn reduce turbulance, if the J-20 applies that it will reduce another signature often overlooked, contrails, contrail detection is another way of detecting Stealth fighters, by using TVC nozzles J-20 will reduce drag and turbulance.

See

Turbulence Reduction
The turbulence of a plane is caused by the movement of the craft disrupting the air around it. The shape of any stealth plane is made so that is EXTREMELY aerodynamic, having the least amount of air resistance. This minimizes the turbulence, and the fuel costs, since the plane is not creating so much drag. The less turbulence, the less likely it is that the enemy's sensitive laser detection equipment will pick up on the plane.



On F-22 and T-50 even contrails have influenced the horizontal stabilizers position see
Air" (moisture) Contrails

"Air" Contrails are the most commonly seen type of contrail. These come from the moisture in the air being disturbed by a wing. When these contrails are created, the pressure of air surrounding the wing is disturbed and unbalanced, causing the moisture to form trails. The F-22 has been able to decrease the likelihood of these contrails because of the horizontal stabilizers located on the aft part of the aircraft. These stabilizers help evenly distribute the lift of the aircraft so that contrails are avoidable

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That conspiracy website doesn't support your claim of TVC reducing turbulence. The only time "vectored thrust" is mentioned on that page is in this sentence:

A multimode electronically scanned radar, internal weapons carriage, vectored thrust and a sophisticated fully integrated sensor array are only some of the revolutionary advantages that Raptor brings to the air combat arena.

No where in this does it says thrust vectoring reduces turbulence.

On J-20 the lower drag long coupled canards generate less drag, therefore reduce detection too

Actually, J-20's canards are not long coupled; they are just not close-coupled. In terms of positioning and relative size to the main wings, they are extremely similar to the setup on J-10.

 

[plawolf]

Stealth only matters at cruise. When significant movement is required from the canards to the point of affecting stealth characteristics, it means the aircraft is already engaging in dog fight where RCS is meaningless.

The famous, or rather infamous American quote that 'the best place to put a canard is on someone else's plane' always seemed more jingoist than factually true. Indeed, considering that it was a Northrop designer who made the claim, and looking at Northrop's 'impressive' portfolio of canard designs, I really don't think he was the most qualified person to be quoted as the final authority on canards. It would be like taking the word of a watercolor master that oil paintings are inferior.

Having properly alined canards as they have on the J20 adds very little to frontal 'static' RCS, and any additional RCS from having canards sticking out on a slightly different plain to the main wings would be more than offset by the J20's far smaller vertical stabilizers in the frontal aspect.

The dirty little secret to 'stealth' fighters and bombers is that the key to success of stealth is mission planning and positioning. That was why AESA radar and supercruising was so high on the ATF's list of requirements. Those tools allow a stealth fighter to detect and enemy first, and then get into the ideal position to avoid detection, and stealth helps him to do now. I don't care how stealthy the designers have made a plane. If you do something wrong/stupid and flash your front or back at 90 degrees to an enemy radar, you are showing up on screen, canard or no canard.

As Engineer already pointed out, any RCS 'balloning' from large control surface deflections is really only an academic distinction, since if you are moving your control surfaces so much that they made a meaningful difference to your RCS, your plane would be doing turns so tight that your entire fuselage is going to be non-optimally presented to an emitter, and you are detected whether you have canards or not.

 

[latenlazy]

I love these shots as they give you a very clear view of what the canards are doing at different stages during a turn.

Hopefully, someone would have some HQ pics of this same sequence, so maybe we can also get a closer look at what all the other control surfaces are doing.

I would also like a closer view at those lines they have put on the left wing at least. You can see them quite clearly on the 4th and 9th images.

Seems like it's actually using the lead edge slats to execute the turn and the canards to trim?

 

[Engineer]

The famous, or rather infamous American quote that 'the best place to put a canard is on someone else's plane' always seemed more jingoist than factually true. Indeed, considering that it was a Northrop designer who made the claim, and looking at Northrop's 'impressive' portfolio of canard designs, I really don't think he was the most qualified person to be quoted as the final authority on canards. It would be like taking the word of a watercolor master that oil paintings are inferior.

Indeed, if canards are so detrimental to stealth, you wouldn't be seeing it on Lockheed's early JSF concept and the X-36.

For those who are new to our board, Air Power Australia has already performed simulation on a J-20 model and concluded that the aircraft meets the definition of Very Low Observable design. In other words, the aircraft is not un-stealthy because of the canards.

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---------- Post added at 07:51 PM ---------- Previous post was at 07:49 PM ----------

Would anyone care to work out the canard deflection in these images to determine the aircraft's AoA at that moment?

 

[siegecrossbow]

Seems like it's actually using the lead edge slats to execute the turn and the canards to trim?

One thing I don't understand is why they aren't using the rear control surfaces to do anything during a turn.