The light four scheme does belong to the first type, fully drawing on the advanced experience of foreign related fields, insisting on the design after focusing on me and carrying out a large number of independent innovations. Pen % fun % Pavilion www.biquge.info

And in fact, if you take a closer look, you will know that there are indeed some Hongdu's technology inheritance in it, first of all, the single-wing design is J-12, L-8 two aircraft are used, and for the design scheme of the air intake passage from above the wing, it should seem quite strange, and even a little deviant feeling, but this design is handy for Hongdu.

The reason why Mr. Lu took these into account in the aerodynamic design of the light four is indeed influenced by the experience inheritance of Hongdu: "The general aerodynamic design of the light four is like this, although the maneuverability of the aircraft can not be regarded as the world's top rank, but it is definitely decent, and at the same time, because the light four has very good stealth ability, first of all, we must not worry about the battle between generations, and it may also be able to fight against the F-22 in the future." ”

In these years, it is difficult for fighters of the same generation to have an overwhelming advantage, even between heavy and light, so it can be said that the light four can have a fighting force with the heavy four in air combat, but in fact, when the two are really opposed, no one will be stupid enough to use light multi-purpose to fight with heavy air superiority head-on air unless it is absolutely necessary.

The aerodynamic design of the light four scheme has been fully disclosed, and the chief engineers who participated in the meeting are all all kinds of bowed heads and pondered, and even more some people asked Chief Engineer Lu for the aerodynamic test data of the light four for multi-party evaluation, or the left and right head to ear communication, each privately expressed their views on the design scheme.

Yang Hui is in a daze on the side, or is thinking about some problems, Qingsi uses a conventional pneumatic layout, although there is a pneumatic turbulence device on the outside of the air inlet to achieve vortex increase, but this still belongs to the category of conventional pneumatics, so the maneuverability is very general, unless there can be any awesome killer design.

Judging from the various situations announced by Chief Lu at this time, the empty weight of this aircraft has almost reached 11 tons, and such data in the thrust-to-weight ratio of the whole aircraft must not be compared with the F-22, a heavy air superiority aircraft with a high thrust-to-weight ratio, and in order to be able to have better maneuverability in air-to-air combat, is it necessary to equip it with a full-motion vertical tail?

In the 90s, there was no clear concept of the full-motion vertical tail, although the earliest full-motion vertical tail design should have been the first introduction of Northrop in the YF-23 project, but that thing was not so much a full-motion vertical tail, as it was a full-motion flat tail with a certain upper and reverse angle to be more vivid and vivid.

Now it is necessary to design a full-motion vertical tail for the light four to increase maneuverability, which is probably a little difficult, after all, the light four first need to carry out overcruise, plus the vertical tail is originally the 2.0 version of the 31 program, and if the time comes, if you still take the full vertical tail design on this basis, I am afraid it is likely to cause the course (yaw) control of the aircraft is difficult, so this thing seems to be easy to use, but in fact it is not very suitable.

Thinking that the 20 of the previous plane did look quite tall after using the full-motion vertical tail, but privately it also paid the price for this design, and the pair of evil pelvic fins existed to make up for the lack of control ability of the vertical stabilizer.

Another aircraft with a full-motion vertical tail design, the Russian T-50 also paid a huge price for this: the ventral groove of the central axis of the aircraft was retained, so that the protruding two air intakes could be used to play a certain role as a vertical stabilizer.

Now, the light four scheme is first of all to directly have a smooth and flat belly like the F-35, so this must not be like the T-50 with two air intakes to act as a vertical stabilizer, and then the light four directly cut off the pelvic fin for stealth design.

This shows that no matter what is done, at least the two schemes adopted by the 20 and 50 aircraft to make up for the inherent shortcomings of the full-motion vertical tail will not work on the light four.

In this way, it can only retain the design of the water safety fixed surface of the light four vertical tails, and honestly adopt the design of fixed vertical tail and hinged rudder surface, and the only thing that can be regarded as making up for the regret is probably to design the hinged rudder surface behind the vertical tail to be larger, and the stabilizer to be designed smaller.

This is a compromise, and the mobility requirement is destined to be sacrificed for the sake of stealth. But it's okay, after all, this is a light fourth-generation aircraft, as long as it can not fall behind in air combat with the F-35 in the future, then the maneuverability index is enough.

Piling up all kinds of high-tech on the light four, although it seems to give people a feeling of not chewing, but the corresponding R&D risk will definitely increase by several grades, and the cost may also rise wildly.

In addition, the research and development time points of the light four and the heavy four are crowded together, and the aircraft with full vertical tail design is absolutely laborious in the flight control, although the flight control development team of AVIC Southwest can be considered to be of great use, but when the heavy four exists as a national key project, the light four projects without strong national support are better not to seize too many resources.

"Well, now the light fourth-generation aircraft scheme brought by Chief Lu should be like this, the aircraft has standard 4S performance, with a certain multi-purpose ground attack capability, but because the size of the light four is not too big, and in order to ensure the need for overcruise, the engine also uses a small channel ratio turbofan, I am afraid that the combat radius can only reach about 1100."

Yang Hui himself can guess the range data of the light four at a glance, after all, this aircraft is first to ensure the need for overcruise, and it is already a very good result to be able to reach a combat radius of about 1100, you must know that this stealth aircraft needs to design the bomb bay, it can be said that it is a variety of hollowing out of the body, where will there be enough space to load fuel!

And this sentence is also deeply approved by the three stealth aircraft chiefs, especially Mr. Lu and Mr. Yu, in order to make the aircraft reach a combat radius of more than 1500 meters, it is simply all kinds of racking of brains, the design of the aircraft body is repeatedly increased, so in the end in terms of size is a typical big guy.

In the future, after the heavy fighters of the Republic come out, they will definitely be larger than the F-22 in terms of size, just like the Su-27 of the year, for the needs of the range, the size of the aircraft should also be larger than the F-15.

"First of all, if the light four can reach a combat radius of 1,100 kilometers, then this is already very good, and you probably understand this as Chief Designer Lu. And I personally feel that the light four program is still very good, the head office is indeed necessary to invest in the development of such a light fourth-generation aircraft, in the future in the international fourth-generation aircraft export market, we can be the first to enter this market. ”

At this time, Chief Engineer Song had a particularly profound understanding of the light fighters for export, that is, the development of aircraft must be carried out as soon as possible, especially this kind of cross-generation aircraft development, because the current No. 10 is obviously losing the first place in the international market competition of the third-generation aircraft, and this project is a little too late to be finalized.

Thinking that in order to make room for the 10th, the domestic army directly stopped the follow-up improvement project of the Lightning, and all the orders were said to be only enough to ensure that the production would be completely stopped by 96, and the production of the Lightning fighter could only be seen abroad in the future.

And this, in the eyes of Chief Song is not something to be happy about, maybe No. 10 can make a difference in the domestic one-third of an acre, so what about the international market? In contrast, although the lightning is about to be discontinued in China, this aircraft is definitely still in the stage of popularity abroad, which is also the envy of No. 10 no matter what, and naturally Chief Song also deeply knows the importance of taking the lead when the fighter is replaced. (To be continued.) )