Chapter 611: The research and development of fourth-generation aircraft relies on data

 Hearing everyone nod their heads.

  The country has not yet self-developed heavy-duty fighter jets. The only domestically developed and successful medium-sized fighter jet is the J-10. The performance of this fighter is very impressive. This is what third-generation aircraft should be like.

 The heavy fighter J-11 currently being produced in China is the authorized production model of Lao Maozi's Su-27. Making changes based on this fighter is also a relatively safe approach.

  However, this also means that the 601 Institute once again chose mediocrity. They did not dare to build a brand new aircraft. They could only tinker with existing aircraft.

“Okay, let’s ask Mr. Gu to introduce the plan of 611 Institute.”

 Lao Gu walked onto the stage, looked at the people below, and opened the PPT.

 What is strange is that the homepage of his PPT does not have a picture of a fighter plane, but some text.

"Everyone, let us first study what is needed for a fourth-generation aircraft." Mr. Gu began his speech: "The Americans have put forward the 4S theory. These theories guide the development of our fighter aircraft. We will introduce them separately. The first One is the stealth capability. On the battlefield, the American F-117 fighter jet has successfully demonstrated the power of stealth aircraft. It only accounted for 2% of the sorties dispatched, but destroyed 40% of the targets. , and they are all high-danger targets. The stealth performance of fighter jets can make it a silent killer in the air. Especially when attacking high-value targets such as enemy early warning aircraft, it is a special skill of stealth aircraft. Therefore, We must first make the fighter aircraft stealthy in terms of appearance."

 In the bidding meeting more than ten years ago, Institute 611 only made a short report during the interval between Institute 601's report, but this time it was different. They had a lot of time.

"At present, several mature stealth aircraft in the world use the same nose layout, with a diamond-shaped nose and a parallelogram air inlet, and the air inlet is just on the two sides below the diamond, achieving aerodynamics and stealth. Perfect integration, so we don’t have any innovations and still use this layout, but in order to improve the fighter’s combat performance, we use a canard layout and a V-shaped cambered double vertical tail layout.”

“In the era of stealth aircraft, which can destroy enemies at long distances, do we still need strong combat performance?” An Air Force boss present spoke.

"If you are facing a non-stealth fighter, you really don't need to get close, but what if the opponent is a stealth fighter? Even if you can't accurately detect and lock the opponent, you will still enter the visual range. Since it is a heavy fighter, the combat performance It must also be its strength. In order to aim the nose of the aircraft at the target faster and gain the opportunity to launch missiles, we continue to use the canard layout."

“The American F-22 has a conventional aerodynamic layout. Does it mean its maneuverability is poor?”

“But the United States has advanced engine technology. If we also have a large thrust engine with a thrust-to-weight ratio of 10, then we may also be able to use a conventional aerodynamic layout. Everyone, the shortcomings of the engine cannot be made up for in a short time.”

 Everyone was silent.

 The one with the highest thrust in China currently is the WS-15, which is an imitation of the R-79 engine. Its afterburning thrust reaches 152 kN, but its weight is also as high as 2.5 tons, resulting in a thrust-to-weight ratio of only about 6.

The turbofan 15 is still being improved. Subsequent models will reduce the weight, increase the thrust, and further improve the thrust-to-weight ratio. However, that is all for the future. In this regard, we cannot expect rapid progress.

The third uncle's thrust-to-weight ratio is also based on the calculation of dry mass, which is barely close to 8. Moreover, the thrust is insufficient and it cannot be used as the power of the fourth-generation aircraft at all.

"When the power is insufficient, we can only make up for it through aerodynamic layout. We use the canard layout in order to improve the combat performance of our aircraft under the condition of limited power." Mr. Song continued to introduce: "We We believe that this solution is currently the most appropriate, and until thrust vector technology matures, this is our best choice.”

  Mobility is not just a matter of high-thrust engines, but also thrust vectoring technology, which allows the aircraft to make more maneuvers. However, this thrust vectoring technology is also very difficult.

The F-22 uses the simplest baffle rotation method, but when rotating, it will lose the thrust of the engine. The American engine has full thrust, and it does not matter if it loses some, but for our own side, the thrust loss is unbearable. .

Da Mao adopts the method of rotating nozzles. The whole nozzle can rotate up and down for more than ten degrees. After improvement, it can even rotate left and right, which greatly improves the aircraft's over-stall maneuverability. The aircraft number 711 that frequently stole the show at European air shows The Su-37 relies on this technology to become famous.

 However, the life of this vector nozzle is very low, only a few dozen hours, which cannot meet the requirements of high-intensity use.

Both technologies have no reserves in the country, and the research will definitely take a long time. The best way at present is to temporarily use conventional engines, and then replace them after the technology reaches the standard. In this way, the canard layout must be used to improve mobility. .

"Similarly, due to the backwardness of the engine, it is temporarily impossible for us to have supersonic cruise capability. For us, long range is more important than supersonic maneuverability. We will wait for the future modified turbofan-15 to mature and replace it with the supersonic cruise capability." This will enable supersonic cruise.”

 At this point, everyone has understood that just like the time more than ten years ago, Mr. Song gradually came to the conclusion through the needs of future air combat: What kind of advanced fighter aircraft do we need?

"Finally, let's talk about the advanced avionics system. As a fourth-generation aircraft, it must use an active phased array radar. According to Mr. Qin's introduction, this radar is already a comprehensive radio frequency system and can not only search for targets. , and can also conduct communications and electronic warfare..."

 An advanced fighter jet slowly took shape during Mr. Song’s introduction.

 It is slightly larger than the F-22. This is a choice made for more fuel capacity, a larger bomb bay, etc. Its maximum take-off weight is also limited to about 35 tons.

"Okay, the two fighters have been introduced. Next, we should talk about suggestions. Mr. Qin, what do you think?" Mr. Lin began to summarize.

“The plans from both design offices are impressive.” Qin Tao said, “However, it would be too hasty to make a decision based solely on these plans.”

Of course, this will not be decided in one meeting. This meeting is just the beginning. At this time, after hearing Qin Tao's words, Mr. Lin continued: "Then what should we do?"

"For a fourth-generation aircraft, the most important thing is stealth performance. Therefore, can we ask two design institutes to each make a quarter-scale model and determine their respective stealth performance in the electromagnetic laboratory? . By the way, during the test, a scaled-down model of the engine must also be installed, so that everything simulates the real situation. Calculate the average and maximum RCS values ​​within the range of 30 degrees forward and 30 degrees sideways of the aircraft."

 One of the features of the fourth-generation aircraft is stealth! Therefore, this performance must be determined, and everything will depend on data.

Mr. Lin nodded: "Yes, let the data speak for itself. No one needs to look for connections. Our air force wants the best performance."

“There is also a wind tunnel to determine the respective zero-liter drag coefficients of Mach 0.8 and Mach 1.5.” Qin Tao continued to introduce.

When he heard Qin Tao say this, an air force boss present spoke: "When we just had the meeting, Mr. Qin said that he was a shipbuilder, but he was an amateur when it came to building aircraft. Now it seems that he is an amateur. , Mr. Qin is an absolute expert!"

Those RCS values ​​determine the stealth of the aircraft, and the following two zero-lift drag coefficients also play a great role in the performance of the aircraft. The value of Mach 0.8 determines the subsonic cruise combat radius of the fighter, and the value of Mach 1.5 is for the future. To lay the foundation, when the engine is powerful in the future, it will be able to carry out supersonic cruise at Mach 1.5 without afterburning, so now it is necessary to ensure that this value is excellent.

"I'm just talking casually." Qin Tao smiled: "The Air Force has to come up with an outline for the specific project indicators, including the maximum lift-to-drag ratio, the maximum lift coefficient for low-speed takeoff and landing, the overload coefficient at high angles of attack, etc. "

 The current bidder is the main engine manufacturer, which is responsible for the overall design. The engine and avionics are all determined by the supporting manufacturers, and they must develop the most perfect airframe!

"That's right, in this bidding, we heard the research and development plans of the two most advanced fighter jets. The next step is to compare the data. We need to study various data settings and formulate the most complete comparison plan." Mr. Lin agreed. : "Mr. Qin, do you have anything else to say?"

"There is another one that should be added." Qin Tao looked at the people below, his eyes twinkling: "There are also R&D funds and costs. The bidding parties should come up with a reasonable plan. During the specific development process, it may be You will overspend, but if you overspend too much, you have to be responsible.”

If you want to develop a brand new fighter jet, you have to spend money. However, this thing is a bottomless pit and must be controlled by budget.

Project No. 10 has been completed. The original total budget was only 4 billion yuan. The scientific researchers used it sparingly, but in the end not enough money was spent.

Seeing the new projects launched by 611, the 601 Institute was unwilling to lag behind and proposed a major overhaul plan for the J-8 II, replacing it with a turbojet 14 engine, adopting a series of new technologies such as new pulse Doppler radar and fly-by-wire control, and developed a A fighter jet of the same level as the J-10 was expected to cost 700 million yuan to develop, but later...

"Yes, we need to have a plan for R&D funding and cost. Our Air Force cannot be taken advantage of." Mr. Lin expressed his stance.

This meeting didn't last long, from eight o'clock to two o'clock in the morning. It was considered over. Qin Tao covered his growling stomach: "It seems that I have to stay for dinner."

Generally speaking, this kind of meeting takes a whole day, but this time it was completed in half a day. Qin Tao played the main role. He proposed a way of using various data to speak in a fair and just way, and solved the problem of the Air Force in one fell swoop. A big trouble.

The lunch for the meeting had been prepared long ago, but it was originally scheduled to start at twelve o'clock. Now it was two o'clock, and everyone was hungry. After arriving in the cafeteria, they started eating immediately.

Mr. Gu sat next to Qin Tao, looking a little worried.

“Mr. Qin, you should have noticed that your plan for our fourth-generation stealth aircraft was originally proposed by you.” Mr. Gu said to Qin Tao.

"Yes, I see it. Your 601 Institute has a very heavy task. You have to revamp the J-11 and design a new fighter. This fighter has indeed gone a step further in design, reflecting your Level." When he said this, Qin Tao glanced at Mr. Gu: "I just don't know, was the shape of this aircraft developed independently by your 601 Institute, or in cooperation with Lao Maozi?"

Hearing Qin Tao's words, Mr. Gu blushed slightly. He hesitated for a moment, and then said: "Mr. Qin, nothing can be hidden from your eyes. The aerodynamic shape of this aircraft is the result of our cooperation with the Sukhoi Design Bureau." Developed together.”

"What?" After hearing what Mr. Gu said, the other people sitting at the table were suddenly surprised.

 The fourth-generation heavy-duty stealth aircraft is the most important project of the Air Force. Such an important project was not developed by itself, but in cooperation with Sukhoi? Then aren’t the secrets of our plane exposed to outsiders?

"Lao Gu, why didn't you say anything at the meeting just now?" Mr. Lin's face became serious.

 As mentioned at the meeting, are there any further opportunities? It will definitely be directly rejected by you!

"Mr. Lin, don't worry too much about this. The aircraft are just similar in aerodynamic shape. As long as the subsequent development is our own, just like the Su-27 fighter jet, once it is in our hands, we can't even change it. Can't you recognize it? We have installed avionics ourselves, and in the future we will even have qualified engines. It is just similar in appearance to the Su-27, but its combat effectiveness has been completely changed." Qin Tao said: "I believe, As the leader of our military aircraft research and development, the 601 Research Institute still has this capability, and I look forward to all the wonderful performances of the 601 Research Institute."

Mr. Song, who was sitting at a table, had never spoken. He still clearly remembered Qin Tao’s analysis: the short engine nacelle layout of the Su-27 series aircraft will inevitably lead to the air inlet directly facing the engine. This design cannot have excellent performance. radar reflection area, so it will definitely be eliminated!

Qin Tao also supported his fourth-generation aircraft with a canard layout. Moreover, more importantly, the J-31A was originally developed by the 611 Research Institute. Although the development department was separated from their research institute by a wall, , we usually meet each other, so they are more familiar with how to develop a stealth machine.

Not to mention anything else, when he just made a model to test the real stealth area, he was confident that it would be better than the 601 Institute, so their 611 Institute would definitely win this time!

At this time, after hearing Qin Tao's words, Mr. Gu nodded: "Yes, Lao Maozi is involved in this project, but the future path will be up to us. In this field, we and Lao Maozi are Maozi is on the same starting line."

Although Lao Maozi's aviation technology is advanced, after all, Lao Maozi has no experience in developing stealth aircraft. They are engaged in plasma stealth and have never been exposed to form stealth. Therefore, Lao Maozi also started from scratch.

The next road needs to be walked by themselves. So far, the 601 Research Institute has not had any good products. The so-called J-8 fighter is just a dual-issue large version of the J-7, and it even has a modified nose air intake. They didn't dare to directly operate the air intakes on both sides. They waited until they got the MiG-23 and mapped the MiG-23's nose before they dared to graft it over. Now, would it be possible for them to do this kind of project? A little too complicated?

 There is no solution to the complexity, they have to give it a try!

The J-10 has been successful, but there is no market for their J-8-3. Now, they must develop advanced fighter jets, otherwise, their big brother will only become an aircraft assembly factory!

After saying this, Mr. Gu thought of something and continued: "Old Lin, our 606 Institute has completed the ground test of Turbofan 10. Next, we need to apply for a fighter jet, install this engine, and conduct aerial test. "

"Has Turbofan 10 completed ground testing?" Qin Tao was also very curious: "Your research and development progress is fast enough."

"It was not developed by us, but by the 606 Institute." Mr. Gu explained to Qin Tao: "Since the introduction of the R-79, our comrades in the 606 Institute have felt more pressure and must develop the engine as soon as possible to give a gift to the motherland. In the end Fortunately, in 1999, I was able to participate in the military parade in the capital."

 Qin Tao frowned.

The turbofan 10 was originally developed for the J-10. This was completely inconsistent with the rules of engine development. After all, the engine development cycle is much higher than the aircraft development cycle. Only when there is an aircraft project, can there be an engine project. , the engine will definitely not be able to keep up!

At the suggestion of Qin Tao, Song Lao made up his mind and chose the third uncle as the engine of the J-10, and finally let the J-10 fly into the sky.

Now, the turbofan ten is in embarrassment. Should we continue to develop it?

Mr. Lin has a long-term vision. After all, my third uncle is from abroad, and there is a risk of the supply being cut off at any time. He still has to rely on himself! Therefore, turbofan ten still needs to be developed! When it is finished in the future, it will not only be able to equip the J-10, but also our J-11!

The turbofan 10 R&D team finally got over the embarrassing situation, but not long after, the turbofan 15 came again!

The size of the turbofan fifteen is slightly larger than that of the turbofan ten, but at the same time, the thrust is also greater. The initial afterburner thrust can reach 152 kN, which is far more than the thrust of the turbofan ten. In the subsequent negotiations with Lao Maozi, , and even planned to replace the third uncle.

This makes the R&D team of Turbofan 10 feel even more pressure. With pressure, there is motivation. Now, they have completed the ground bench test and plan to install it!

"If you want to conduct an aerial test run, it is not appropriate to use our J-10. Our aircraft is a single-engine aircraft. Once a malfunction occurs, it will easily cause the aircraft to crash." Mr. Song spoke for the first time: "It is most suitable to use the J-11 , one side installs the turbofan 10, and the other side installs the third uncle, so that if the turbofan 10 fails, the flight capability can still be guaranteed."

Mr. Lin nodded: "That's right, let's mobilize a J-11 to go there. They are all in the same city anyway, so it is easy to mobilize them."

After finishing speaking, Mr. Lin glanced at Qin Tao: "Taozi, what's going on with your expression? Do you have any ideas about this engine?"

Of course Qin Tao has some ideas. There are many problems with the early turbofan ten!

There are too many problems such as low-altitude large surface speed surge, fourth-stage compressor blade breakage, mid-air parking, etc. It would be a big mistake to think that after the bench test is completed and installed on the aircraft, it is done.

However, Qin Tao also knows that the road to engine research and development is so uneven, especially when it is developed from scratch, there are many problems. Solve problems when you encounter them, continue to solve them, and constantly optimize, so that they can eventually mature.

From Turbofan 10 to Turbofan 10A, they were all models with problems. When it came to Turbofan 10B, the performance finally stabilized and began to be installed on the J-11. When it came to Turbofan 10C, it could still be installed on the J-11. The J-20 is assembled, and there is even news that it has supersonic cruise capabilities.

At this time, it is not only high reliability and long life, but also the thrust is first-class! The maximum thrust is similar to that of R-79, but its weight is light and its thrust-to-weight ratio is high!

"Mr. Qin, do you have any opinion on Turbofan 10? Do you think it is not as good as Turbofan 15?" Mr. Gu also became nervous. Although Mr. Qin is a shipbuilder, he also has great influence in the Air Force. Ah, if he says he doesn't like it, the Air Force might give up.

Qin Tao shook his head.

Turbofan 15 was built with his support, and he even hired a lot of experienced experts, while Turbofan 10 was built by himself. Both projects seemed to be high-thrust engine projects. , are they competing with each other?

"The Turbofan 10 project is of great significance." Qin Tao began to explain: "Our J-10, J-11, and even the future J-15 and J-16 will all be powered by it. Today's aircraft have a long service life. As for the life of the engine, when these three uncles fly to the end of their life, then the engine can be replaced, and then we can replace our turbofan."

"And our turbofan 15 is prepared for fourth-generation aircraft. Its starting thrust reaches 152 kilonewtons. In future modifications, the thrust can reach 181 kilonewtons, or even more than 200 kilonewtons. With it, the fourth-generation aircraft can finally achieve the supersonic cruise indicator." Qin Tao continued: "The installation targets of these two engines are different, and they are not in a competitive relationship."

 Mr. Gu breathed a sigh of relief. Looking at Qin Tao's expression just now, he thought he was dissatisfied with Turbofan Ten.

"I just thought of the tortuous experience that the Americans went through when developing third-generation fighter engines. Therefore, we'd better be mentally prepared. After the turbofan X is installed, it may take five or even ten years. Perfect." Qin Tao looked at everyone seriously: "If you have a good meal, don't be afraid of being late. We must have enough time to prepare."

Mr. Lin nodded: "Yes, we built the Turbofan 10 ourselves, and we will inevitably face various problems. However, no matter what problems arise, we hope that our technicians can use their talents to find the problem correctly. Don’t be discouraged or discouraged, our Air Force fully supports Turbofan 10.”

 (End of this chapter)