Yang Hui naturally can't care so much, now is the time for him to report, and everything is mainly based on reporting projects.

After a brief self-introduction, Yang Hui's information about himself and the base, began to report the plan.

The two slides are projected together, and the design of the new machine jumps into view.

When they saw these two plans, everyone was still puzzled, although this plan could be seen to be developed from J-7, but it was obviously very different from J-7.

"As you can see, we have a total of two plans for the new machine, and each plan has its own focus, advantages and disadvantages."

There is no need for Yang Hui to continue, after Prince Sultan and Madad looked at the model in their hands together, He Nie Shuai exchanged with each other, and after seeing the real model, he naturally had a deeper understanding of the two schemes.

Madad was the first to ask: "Can such a modified new aircraft really simulate the flight performance of the J-7?" Especially in the air intake, I think the two new machines have abandoned the nose air intake. ”

The Pakistani side's doubts about the new scheme of the two air intakes have been demonstrated for a long time and there is no problem.

"There is no problem at all, we follow the requirements for the use of the J-7, and at the same time in order to ensure the high angle of attack flight capability of the air intake. The two-rib air intake scheme uses the inversion under the air intake, while the downward air intake has excellent high angle of attack flight performance. ”

Hearing such a new modification is not a big problem for the imitation of the flight performance of the J-7. The Republic of Pakistan is relieved, and now the first priority is to do a good job in the flight training task of the Jian-7 pilot, of course, if it can achieve a high angle of attack flight like the F16, Pakistan will be even happier.

Continuing with the advantages and disadvantages of the two types of air intakes, it is best to determine which scheme to use as soon as possible.

"Two schemes, first of all, the two-rib air intake, the disadvantage of the two-rib air intake is that the arrangement of the air intake will be more abrupt, when the air is inhaled on both sides and goes into the body, there will be a relatively large bend, and it is easy to form a small vortex, which is not very good, but the advantage is that the air intake is separated from the ground by a high level, and it is not easy to suck in sand and gravel."

Speaking of which, it is more difficult to listen to the report below, the advantages and disadvantages of these two ribs are more obvious, if you want to make up your mind, you must first listen to the plan of the next air intake.

Nie Shuai doesn't know much about the specific aspects of the aviation industry, but it doesn't matter, just ask if you don't understand.

"Okay, you're talking about the pros and cons of the other plan, let's hear which one to choose."

Remove the two-rib air intake scheme renderings from the projector and place the lower air intake renderings in the middle.

"You can see that the advantage of the down-intake design is that it avoids the valuable space under the wing, where a close-range combat bomb can be mounted. At the same time, the air intake of this solution will be smoother, but the disadvantage is that it is easy to suck in sand and gravel. ”

This is clear, the advantages and disadvantages of the two-point plan are mutual, your advantages are its disadvantages, and its advantages are your disadvantages.

Thinking of the design of these two schemes, it is still a headache to choose, of course, the headache is in front of the domestic army, and Madad has already had a choice.

"In this case, as long as we can ensure the flight at a high angle of attack and the vortex of the intake tract can be effectively solved, we will choose the two-rib air intake."

Madad said very decisively, and Prince Sultan naturally followed Madad's wishes. Although looking at the model in my hand, the air intake is indeed quite abrupt and does not look good, but it doesn't matter, as long as you don't inhale sand and stones, you can bear it. Saudi Arabia is located in a desert area, there is a lot of wind and sand, if the use of lower air intake, I don't know how many accidents will occur.

Putting down the model in his hand, Prince Sultan also said: "I agree with Madad's opinion, what we need is the ability to take off and land under harsh conditions, and as for hanging missiles, we don't need to install so many training missiles on the training aircraft." ”

What else to say, the foreign side has chosen the two-rib air intake, then the two-rib air intake is good.

Originally, it was a little difficult for the army to make up its mind about this choice, but now that the foreign side has decided, then it will be better to follow the foreign side, anyway, there was no new hanging point for Jian-7 before.

Finally, the army also agreed to use the two-rib air intake scheme, then the two-rib air intake is good, and the slide is replaced with a top view of the two-rib air intake scheme.

"Well, as you can see, the airfoil of this new aircraft is different from the airfoil of the J-7, the new aircraft adopts a double delta wing layout, and at the same time we have added a leading edge maneuvering flap. In this way, the new aircraft's ability to maneuver at medium and low altitudes will be greatly improved, and it can also retain the high-altitude flight performance of the J-7 at the same time. ”

Hearing that the new aircraft uses a double delta wing, the military is interested, and this double delta wing is indeed a good design for this purpose. And with the test of the new training aircraft, it can be directly installed on the J-7 in the future, which is very good, and now we have to make this technology when we have the opportunity.

It can improve the flight performance of the new aircraft at medium and low altitudes, which is not bad, if the new aircraft is designed in this way, the new aerodynamic design can indeed be close to the performance of the third-generation aircraft. In this way, there should be no problem in achieving the required 50 percent of the third-generation aircraft flight training subjects, but there is still one thing to really achieve this 50 percent flight performance.

Thinking of this, Madad asked the question again: "In terms of aerodynamic design, the new machine has indeed achieved our design requirements, but the pneumatic aspect alone is obviously not enough, how do you plan to arrange the control system?" ”

It is impossible to achieve the flight quality of the third-generation aircraft with excellent aerodynamics alone, and if it is still in accordance with the control system design idea of the second-generation aircraft, it will be difficult for the new aircraft to fly. In order to widen the gap between the third-generation aircraft and the second-generation aircraft, the design of relaxed static stability is adopted.

How to stabilize the static width? To put it simply, it is to make the wing area larger, under the same weight, the wing area increases, then the unit load of the wing can be reduced, the unit load is reduced, and the maneuverability will naturally go up.

To put it simply, the static stability is relaxed, and the control of the aircraft is also difficult, at this time the traditional mechanical control system can not be satisfied, and it is natural to introduce a more advanced fly-by-wire system (except for the freak of the MiG-29).

In the design of the new aircraft, a double delta wing was used to enhance maneuverability, and at the same time, on the aerodynamics, some static stability was slightly released.

For the control of slightly relaxed stability, there is already an initial plan in the design, which is what Yang Hui is about to say: "For the new machine, we have appropriately relaxed the static stability, and we have modified the original control system of the J-7 for this purpose, and adopted analog fly-by-wire stabilization." A full set of mechanical control systems is retained, and a three-redundant analog fly-by-wire control system is used in the longitudinal direction, which is enough to ensure the flight stability of the new aircraft. ”

Having said all this, it is said that this new aircraft is still not a complete fly-by-wire aircraft, but it has adopted a surplus of three degrees of fly-by-wire in the most important and unstable longitudinal aspect, which is really better than nothing, after all, the new aircraft has only slightly relaxed the static stability.

In fact, even the new aircraft can be used without fly-by-wire, which is for insurance, and at the same time allows the new aircraft to simulate the performance of some third-generation aircraft more reliably, and the most important point is that you can take this opportunity to study the new fly-by-wire flight system to lay the foundation for the development of new aircraft in the future.

The telex system is a lofty name, at least for the current republican ** side, the eyes of the current army representatives are red, this is really not easy, the research institute in this mountainous area has found such a large amount of money, and now even the telex has begun to be studied, high-end.

Pakistan didn't expect this to do this to control the system, what should the new machine that came out of this be counted? No, the second generation is still something.

Prince Sultan is the Minister of the Air Force of Saudi Arabia, and he is very interested in the plan proposed by Yang Hui, and he is also more optimistic about the research and development of the new aircraft: "Your plan is quite reliable, there are advanced places, and there are conservative places, although the new aircraft has risks, but the risks are not too great, and it is possible to achieve 50 percent of the flight performance of the third-generation aircraft." ”

Hearing that Prince Sultan was very optimistic about the new machine, Yang Hui happily said the positioning of the new machine that he had just thought of.

"This new machine has surpassed the ordinary second-generation aircraft, and now it should be called the second-generation and a half."

The term two and a half generations is not there now, the second and a half generations are the three and a half generations invented by the French, and there are only a few and a half generations of the saying, and now Yang Hui has introduced this statement in advance, which is used to show the difference between the new machine and the second generation machine, so as to improve the compulsion.