J-20 5th Gen Fighter Thread VI

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anzha

Senior Member
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This is probably what the actual J-20 cockpit looks like:

Um. If I may though, didn't the flyby with the open bays pretty much show the J-20 only carries 6 missiles internally? 4 in the main bay and 1 in each of the side bays?
 

siegecrossbow

General
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Henri K take on the J20 demonstration in Zhuhai airshow Interesting interview with Li Gang the test pilot for J 20. When ask to the performance of J20 the pilot said that J20 is as agile as J10. That should put and end to the myth that J 20 is underpower
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Airshow China 2018: Cockpit, Weapon bay, demonstration ... the J-20 is unveiled more
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2e8d649e1b274ce816887d2ce17d9964

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As in 2016, the J-20 fighter of the Chinese Air Force is present again this year in Zhuhai-Jinwan for the 12th edition of Airshow China 2018. But compared to two years ago , the aircraft dubbed Wei Long (威龙) by its designer the 611 Chengdu Institute of AVIC has unveiled more, whether in number of public presentation or demonstration content.

Starting with the number of aircraft - At the 2016 Zhuhai Air Show, while the aircraft's entry into service with the People's Liberation Army Air Force was not yet announced, two J-20 made a brief appearance of one minute during the inauguration of the event by flying over the runways of Zhuhai-Jinwan Airport. This year, the J-20 has more than doubled its presence at the same show and a total of four aircraft has come to deliver flying demonstrations for four days on the 6th, 9th, 10th and 11th of November.

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If the J-20 is still not exposed to the ground so that visitors can watch it closely, as the F-22 and F-35 have done at some air meetings, it remains that PLAAF has been much more open, and also more confident, to reveal and talk about its new spearhead dedicated aerial domination.

For example, interviews and press conferences were held last week in Zhuhai for the media to have the opportunity to speak live with the J-10B, J-20 and Y-20 pilots. LI Gang, who took charge of the first inaugural flight of J-20, has
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.

"It's transcendent (梦幻) ...", LI used this one word to summarize and answer the journalists' question about his J-20 flying experiences, a word that leaves room for imagination.


As for the cockpit of the aircraft that has never been shown to the public, the Chinese test pilot indicates that the cockpit of the J-20 is not only large and simple but especially very user-friendly.

"Everyone who has seen the J-20 cockpit is amazed by its simplicity and user-friendliness. Any switch or button, at a glance or touch we understand its function, day and night. LI said, "Chief Engineer YANG Wei gave us empty cockpit plans and stickers representing switches and buttons. And he asked us to stick them to the place that we think is the most reasonable on the plans. "

The shots from each elite pilot are then compared and compared to the others, and at least five rounds of review and selection took place during the development of the aircraft. From the plan on paper to the wooden model, then to the metal model, the engineers and pilots participating in the program worked on the smallest detail to arrive on an integrated mono-screen cockpit that they describe as a "science fiction" ".

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I've given it up as a lost cause. Some people only see what they want to see.
 

foxmulder_ms

Junior Member
Tails generate positive lift and drag too. You don’t really think air decides to skip flowing over the tails because they’re tails do you? Yes, that positive lift might be smaller per area because of downwash from the wings, but that’s why tails tend to be bigger, to generate the same amount of pushing force needed to pitch the plane. Meanwhile that drag from being an object that interacts with the air stream is still there. In fact with that combination of being just as present to the air stream and typically larger size due to control demands it could be argued that tails in general generate as much drag as or more drag than canards (to be clear I’m not saying that a plane with tails is always draggier than a plane with canards, as always I dislike drawing hard conclusions about specific designs based on superficial cherry picking of individual features).

I’ve also given this canard stealth thing some thought, and I’m not sure the prevailing conclusions are correct. They sound more like erroneous extrapolations of some laymen heuristics. If we think about how RF backscatter against a wing works, the incidence angle the wave encounters is what determines their angle of reflection. Against a plane’s surface this is determined by sweep angle, which is true for both the canard and wing. If their sweep angles match they should be reflecting the RF wave in the same direction. In this sense the general amount of RF energy reflected back to the source for a canard surface is at most a linear addition to the amount reflected back by the wing when the canard edge doesn’t block direct line of sight to the wing, and a non contributor in the general sense when the canard edge is coplanar to the wing edge, at least in terms of total energy. This may mean that in terms of total possible energy a canard+wing is reflecting the same amount of total energy as a larger wing, as more surface always equals more energy reflected, but when that is the case the extra contribution of surface from a canard, like with a larger main wing, shouldn’t be noticeably significant because backscatter depends on *area*, and edges for small surfaces don’t have a lot of that, and in addition that area is *effective* area, which isn’t defined by physical dimensions alone but by how reflective the physical object is to the RF wave, which should be much less for surfaces treated to dampen RF reflection.

Despite all that, the typical argument against using canards comes in three flavors. The first is that as an additional object exposed to the RF wave canards will generate their own dipole lobe (the beam of RF energy reflected away from the source) separate from the wing. However, so long as the canard shares the same sweep as the wing the angle of their dipole lobes will be the same, which is to say they should be reflecting RF energy in the same direction, which then therefore means the canard’s extra dipole lobes shouldn’t disrupt the “bowtie” shape generated by the wing to forward facing RF waves. A canard with the same sweep as the wing should therefore at worst only have negligible extra contributions to frontal RCS, and at best make no difference (with the dipole lobe of the canard being totally indistinguishable from that of the wing and the rest of the fuselage), except when extra exposed edges contribute some extra area for the RF wave to interact with, which itself should be minuscule for treated surfaces.

The second kind of argument is the traveling wave problem, where as a function of being in front of the main wing the traveling wave that propagates along the canard’s surface exits from the canard’s trailing edge and interacts with the main wing in a more scattered fashion, which makes that portion of RF reflection more difficult to control. If the canard is either reflecting or dampening most of the RF energy hitting it though the additional contribution of RF energy propagated to the portion of the wings behind the canard should be quite small, smaller still if that portion of the wing is treated to dampen RF reflections, and even smaller if the canard also has their trailing edge treated to dampen RF reflections. Furthermore, the angle at which those traveling waves are reflected once they exit the trailing edge may be effectively controlled by metamaterials to reflect that energy in a more favorable direction and further limit their interactions with the main wing. In the J-20’s case, the canards being angled at a dihedral rather than being coplanar may actually help reduce this component of RF reflection. The trade off is of course more of the wing edge behind the canard is exposed, so you get that linear addition I mentioned earlier, but again that may end up being negligible.

The last kind of argument is that the canards, by adding an extra wing root, adds an additional corner reflector. In the J-20’s case though the canard wing root is coplanar with the main wing, so there should only be one corner reflector facing forward. Of course all these arguments apply strictly to forward facing RF waves. For azimuths that look more sideways or vertically, canards may actually be a bit better than horizontal surfaces, since at those angles line of sight to the tails aren’t being blocked by the main wing, and tails tend to be much larger than canards.

Tails generate negative lift.
 

foxmulder_ms

Junior Member
:) You guys are crazy to think that 4 is maximum in this bay, look how much more space there! You think designers are going to waste that much space? Have some fate. Also the connection points for the 3rd pylon is visible. You don't need to pixel count to see the ample space.

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3rd missile offset towards front will do it. Or very close to clearing and a "taller" pylon + curvature of the missile radar dome will help fitting in. It is a similar config with F-22 loading. The 3rd, middle missile will be more towards front and lower.

Anyhow, we may see it maybe in 5 years. I dont expect a picture with 6 missiles for a long time. PLAAF is hiding it.

Also as said, third pylon connection points are there, visible. Space will not be wasted like that. The mission of this plane is air supremacy and it is designed for that in mind primarily not for some bigger A2G weapon.

I even think that with a smaller AIM-120 like missile, 8 is possible. Look how tightly packaged AIM-120s in F-22, all are at different depth too:

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Blitzo

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:) You guys are crazy to think that 4 is maximum in this bay, look how much more space there! You think designers are going to waste that much space? Have some fate. Also the connection points for the 3rd pylon is visible. You don't need to pixel count to see the ample space.

3rd missile offset towards front will do it. Or very close to clearing and a "taller" pylon + curvature of the missile radar dome will help fitting in. It is a similar config with F-22 loading. The 3rd, middle missile will be more towards front and lower.

Anyhow, we may see it maybe in 5 years. I dont expect a picture with 6 missiles for a long time. PLAAF is hiding it.

Also as said, third pylon connection points are there, visible. Space will not be wasted like that. The mission of this plane is air supremacy and it is designed for that in mind primarily not for some bigger A2G weapon.

I even think that with a smaller AIM-120 like missile, 8 is possible. Look how tightly packaged AIM-120s in F-22, all are at different depth too:

J-20 most likely will be able to carry 6 BVR AAMs in future, but it will have to be a new missile.

It will not be able to carry 6 PL-15s, and they will not stack AAMs because stacking AAMs introduces additional more complex deployment pylons as well as causing the risk of backing up missiles deeper in the bay if the lower missile fails to fire.

Yes, J-20 has attachment points in the middle for a third pylon. But it won't be used to carry a PL-15. There is simply insufficient space and PL-15 is too big of a missile to allow six PL-15s to be carried, and the stacking of missiles is unprecedented.
 

latenlazy

Brigadier
Tails generate negative lift.
A tail, when stationary in the free stream, generates positive lift. The “negative lift” from when the tails deflect is negative *relative to the lifting force on the wing and relative to its stationary position*. Either way though we can nitpick the semantics and it doesn’t change my point.
 

Richard Santos

Captain
Registered Member
It looks to me like there is enough clearance in front of the nose of the two missiles currently in the bay that a third identical missile can be placed offset to the front to fit between them and provide clearance for the missile fins. It would well be that stowing and launching such a third missile in the middle requires a different trapeze design than from the two missiles on either side, and the center trapeze is not yet ready for service.
 

Blitzo

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It looks to me like there is enough clearance in front of the nose of the two missiles currently in the bay that a third identical missile can be placed offset to the front to fit between them and provide clearance for the missile fins. It would well be that stowing and launching such a third missile in the middle requires a different trapeze design than from the two missiles on either side, and the center trapeze is not yet ready for service.

The PL-15 is too large for such an arrangement. I think there's been enough imagery analysis over the last day or so in this thread and others that there simply isn't enough width.
 

Blitzo

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Generally speaking, I think there has been enough of a chorus among various big shrimps over the last day or so essentially confirming that J-20 can only hold four PL-15s. I think that makes any debate over whether there might possibly be just enough space between the two missiles for a third to be squeezed in if XYZ was done, to essentially be fruitless.



At this point, I think J-20 carrying 4 PL-15s internally at a maximum should essentially be considered a done deal.

J-20 will probably sooner rather than later be able to carry 6 BVRAAMs internally, but that will be with a new missile.
 
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