Qin Feng returned to Chengdu and entered the intense work, if it was just to make a model, it would not be difficult, but first of all, Song Lao would first determine the basic data of the new annihilation, so that he could make a model, otherwise, the model is not the same as the real data, it is absolutely impossible.

One of the most basic elements of the canard layout is the size of the canard area and the distance between it and the rear main wing.

The main role of canard wings is two, one is to provide a moment to make the fighter raise its head, in this way, the farther the distance, the less torque is required, as long as there is enough distance, Archimedes can use a lever to warp the earth.

But at the same time, the canard wing has another function, that is, it is used to pull the vortex.

If you want to improve the maneuverability of the fighter, you must take advantage of the continuous development of aerodynamics, in the past, the variable sweep wing is a manifestation of the development of aerodynamics, through different sweep angles to obtain the most efficient flight ability, but unfortunately because the material is not strong, the increase in weight is offset by the advantage, but also brings the problem of control.

Now, the development of aerodynamics is the use of vortices, for example, there are edge strips on both sides of the fuselage of the J-13, which are used to pull the vortex, and this special air flow has a high improvement in the aerodynamic efficiency of the wing at high angles of attack.

The canard wing can also pull the vortex, and the vortex pulled out by the canard wing will be coupled with the vortex on the upper surface of the main wing to improve the lift of the main wing, the greater the lift of the main wing, the better the performance of the fighter.

In this case, the farther the canard wing is from the main wing, the more severe the loss of the drawn vortex and the worse the coupling effect. When this distance is far enough, the vortex of the canard wing and the vortex of the main wing will no longer be coupled, and there will be no lifting effect.

So, from this point of view, the closer the canard wing is to the main wing, the better.

These two needs are completely contradictory, how to balance them?

"Although there is no large-scale canard layout of fighters in the world, this trend is obvious, and we can see that in Europe, various aircraft companies have studied a lot of canard layouts and published a lot of papers." It was Qin Feng who spoke, and in this regard, Qin Feng has also been researching, especially after taking over the sorting of J-9 data, Qin Feng has turned over this kind of research at home and abroad.

"Dassault, it's more of a close-range coupling." Qin Feng continued: "Eurofighter tends to be coupled at a long distance. ”

Europe already had Tornado fighter-bombers, but unfortunately the congenital defects of this fighter made it the most suitable as an attack aircraft, in the face of the armored clusters of the Soviets, to strike from the air.

Only the version of the interceptor of the Tornado fighter by the British did not call it a fighter.

It lacked maneuverability, so Europe wanted to jointly develop a fighter with the goal of air superiority, and in 1979, British Aerospace and Germany's MBB submitted a formal proposal for the ECF (European United Fighter) to their respective governments.

As soon as the French saw that they had the opportunity, they hurriedly joined in, so that the three countries were the most important countries in Europe, so the fighter they jointly joined was called "Eurofighter".

However, the facts later became clear, the French were absolutely not at ease, they joined in, it was because they wanted to lead, Dassault was arrogant, Dassault insisted on leading all the design, especially the engine of this fighter, must use Dassault's own M88 engine.

Although Britain has declined, but after all, the emaciated camel is bigger than a horse, especially in terms of aero engines, Britain's technical strength is quite strong, turbine engines, almost from them, their engines, even the United States admires, imported.

The British can still take a breath of relief, but in terms of engines, the British are firm and insist on using the Turbo-Union RB199 engine.

The French saw that they were not doing it, and they joined in, just to dominate everything, and the British insisted, and they simply played on their own.

In this way, Dassault withdrew and went it alone, and the remaining companies continued to develop, which came up with two plans.

Dassault, the most slippery play is the delta wing, look at the phantom machine, almost all of them are tailless delta wings, for Dassault technicians, the canard wing does one thing, it is enough to produce vortices for them, and the rest depends on the main wing to solve, there was no main wing before, isn't it also a good play.

Although the Rafale has not yet come out, such a plan has already come out when they are dominated by the Eurofighter project.

"That's right." Song Lao said on the side: "Close-range coupling, the relative distance between the main wing and the canard wing is very close, and the root of the canard wing even overlaps with the projection in front of the main wing. Because the canard wing can produce a strong air vortex during flight, and the canard wing vortex is easy to coincide with the lift vortex above the main wing, the lift coefficient of the main wing can be greatly improved, and the characteristics of maneuverability, payload and range can be significantly improved. ”

If you look at the Rafale fighters of later generations, it is like this, the rear end of the canard wing, almost above the front end of the main wing, coincides with each other, and the vortex is used to the extreme.

"But the disadvantages are also obvious, the canard lift effect is obvious, the control effect is small, in order to balance the lift and gravity, this close canard wing is either fixed, or small action, the control characteristics are mainly reflected in the aileron or tail."

Song Lao has studied these things for more than ten years, and of course he is clear.

"As for the other one, it's long-distance coupling." Song Lao continued: "The relative distance between the main wing and the canard wing is relatively far, and the projection distance is much longer than the canard wing, and the canard wing is relatively small. At this time, the canard wing area is small, the wingtip vortex is small, and because of the long distance, the coupling effect of the vortex is small, and the improvement of lift characteristics is limited, but due to the small coupling with the main wing lift, the lift is relatively independent, and the control effect is very good. ”

Differential, that is, the two wings of the direction of action are opposite, in this case, it can make it easier for the fighter to roll up, the third generation aircraft, the roll rate is a very important factor, which can be played in the long-distance coupling, of course, the design of the flight control is also a great test, a little careless, is the result of the crash.

In terms of the fly-by-wire flight control design of the third-generation aircraft, it is still blank.

1 second to remember Aishang:. m.