Chapter 570 Il-76 and Yun-20

  One of the most important reasons for the establishment of the Yun 20 project is the needs of the Air Force, such as early warning aircraft, refueling aircraft, and ordinary transport aircraft. These requirements are all looking forward to the emergence of large aircraft.

In China, XAC manufactures large aircraft. Yunba was originally surveyed and mapped by 603, and then handed over to XAC for production. Now, after 603 has produced the Flying Leopard, it is still looking forward to a large aircraft project. .

  Because there is no project approved, it has been doing self-research. Now, if the Air Force wants to obtain strategic transportation capabilities, it must have a large-scale transport aircraft produced by itself!

   At this time, hearing Mr. Lin say this, everyone present cheered up.

  Qin Tao also felt very excited.

  Originally, Qin Tao came here to participate in the emergency response after the Feierkang early warning aircraft project was stopped, but due to the preparations made in advance, the topic of this meeting changed quickly.

  If you want to completely solve the problem of early warning aircraft, you still have to have your own airframe platform!

   "However, it is not easy for us to independently develop a large aircraft. Whether it is the engine, the aerodynamic layout, or even a simple landing gear, it is blank for us." A leader on the scene spoke.

   "That's right, even if the 603 Institute conducts pre-research, there will still be a long way to go." Another leader said.

   "Boss Qin, do you have any ideas?" Elder Lin looked at Qin Tao.

  Qin Tao realized in an instant that although he was a shipbuilder, his relationship with the Air Force was getting deeper and deeper. On this big issue of military equipment development, Mr. Lin still hoped to seek his own opinion.

"First of all, the biggest problem with the large aircraft project is the engine." Qin Tao also said: "Our country is currently immature except for the turbofan-15, so if you want to start the large aircraft project at the same time , and the large bypass ratio turbofan engine dedicated to large aircraft will definitely not be able to keep up with use."

The problem of shortage of domestic aircraft heart has always existed. The J-31A can quickly mature, which is related to Qin Tao’s promotion at the beginning. The entire R-79 engine information was purchased, including the production and processing technology of various rough materials, and All kinds of equipment can be said to be the same as when industrialization was realized with the help of Lao Maozi in the first five-year plan, so the imitation of WS-15 did not encounter any problems.

   But other things are different.

   Both J-10 and J-11 are looking forward to using turbofan 10, but the success of this engine is still far away.

  If you want to launch a large aircraft, you must have a special engine. This kind of engine is different from that used by fighter jets. Apart from the difference in the afterburner, it is the bypass ratio.

  The turbofan engine is equivalent to putting an external duct on the outside of the turbojet engine, directly thinking about blowing air, thereby increasing the thrust and reducing fuel consumption. However, fighter engines have to consider the issue of windward area, so the bypass ratio generally does not exceed 1.

  Transport aircraft are different. The larger the bypass ratio, the more fuel-efficient. As for the increase in the windward area, the problem of increasing the windward area is not considered. Anyway, the transport aircraft does not need supersonic speed.

The D-30KP-2 engine on Lao Maozi's Il-76 has a bypass ratio of 2.4, while the turbofan-20 independently developed in the later generations has a bypass ratio of more than 4, and the airliner's engine has a bypass ratio of 2.4. More than ten!

  There is no technical reserve in China.

   "When our Turbofan 10 is fully developed, we can add a large external duct to the core engine of the Turbofan 10 to become the engine of a transport aircraft." A leader of the Air Force said.

   "That's right, if the progress of Turbofan-10 continues to be delayed, we can still make changes to the core engine of Turbofan-15."

  Big guys put forward their opinions one after another.

  Although the engine is different, the core machine can be exactly the same, which is what the West does.

"The engine can be developed on our core aircraft, but it still takes a long time for research and development. Therefore, if we want to build a large aircraft, we can first purchase the D-30K engine from Lao Maozi and use it on our transport aircraft. Anyway, our Relevant units are already using this engine to improve the H-6," Qin Tao said.

   For a long time, the H-6 was the only heavy bomber in China. Because of its high take-off weight, it was even converted into an aerial refueling aircraft for use with the J-8.

  The turbojet-8 originally used by this aircraft had high fuel consumption and weak thrust. After the collapse of the Red Empire, the relevant units began to study the use of Lao Maozi's engine to replace it.

  Of course, this improvement still caused the technicians a headache for a long time. After all, the diameter of the D-30KP2 turbofan engine planned to be modified is 20 cm larger than that of the turbojet-8 engine, and the requirements for air intake have also increased. The power cabin needs to be remodeled, and the air inlet and tail nozzle have to be widened, so that the D-30KP2 turbofan engine can barely be installed.

  Because the engine power is too strong, the thrust has to be reduced on the H-6.

   As the Il-76's engine, Qin Tao put forward his first opinion: If we want to build a large aircraft, we must have an engine. On the premise that our own engine is not mature, we must first purchase the old Maozi's engine.

Moreover, since the transport planes all use pods, it is easier to change the engine. In later generations, there was a similar scene: three of the four engines were the same size, but one of them was a lot thicker , because this one is a domestic product, and the other three are Lao Maozi's.

   "That's right, we can't wait, just like the J-10, we use imported engines first, wait until the performance of the domestically produced ones stabilizes, and then replace them with domestically produced engines." Elder Lin nodded immediately.

   "The next step is the research and development of the airframe. Lao Maozi's Il-76 is very good. I suggest you can refer to the design of the Il-76."

  After Yun-20 came out, its appearance was very similar to Il-76, so that it was said to be a copycat, and the names of Cheng Luoma, Shen Huoyi, and Silyushin spread.

  Actually, the reference must have been referenced, but it is still different in many places. The body of the Y-20 is wider, and there is no need to remove the tracks when transporting the tank. The wing airfoil of the Yun-20 is also very different from that of the Il-76.

   It is normal to learn from foreign aircraft. After all, the Il-76 is a very mature transport aircraft. Of course, we must take its essence and discard its dross! It can be said that even if it is imitated, it is quite good. If it is improved, it will be even better.

   Now, if 603 is going to do it, it must also be referenced.

"Now, the Il-76s equipped in our army are very precious, and they must not be taken out to be disassembled by the 603 for surveying and mapping." Elder Lin said to Qin Tao: "Mr. Qin, is there any way you can get the Il-76?" The design data of -76?"

  Qin Tao came to his senses. I'm afraid this is the main purpose of Mr. Lin calling him here!

  Whether it is the navy or the air force, they all need large aircraft. This kind of aircraft cannot be completely relied on outsourcing. No matter how much you buy from outside, it is not enough.

For a country that has never developed a large aircraft, the best way is to imitate it by surveying and mapping, and then improve it. However, the imitation of surveying and mapping needs to provide a prototype. Given the current domestic equipment, it is too extravagant to provide a prototype. Therefore, the air force put the idea on Qin Tao's head, hoping that Qin Tao could help.

   After all, this kind of thing has been done more than once.

"Il-76 materials mainly exist in two places. The Ilyushin Design Bureau must have a full set of materials, but it is too difficult to get the materials from them. They can only be purchased through regular channels. The price It will also be very expensive." Qin Tao said: "Another place is the Chkalov Aircraft Factory."

"That's right, Mr. Qin, we think so too. As long as we operate well, we can pack the data of Il-76 from the Chkalov Aircraft Factory." Elder Lin said, "However, this kind of thing You're still the best at it."

  Qin Tao has done similar things many times, of course he is familiar with it.

  Hearing what Elder Lin said, Qin Tao could only smile and nod: "I can try it."

   Dealing with David’s breach of the contract is still secondary. Next, it is important for our own side to independently produce advanced large transport aircraft.

Qin Tao has been to the Chkalov Aircraft Factory more than once, but he has been in China for the past one or two years, so he doesn't know if the people there have changed. However, since last year, the Chkalov Aircraft Factory has almost It is in a state of shutdown, so the situation there must be very difficult.

   "You guys always find me something to do before the Chinese New Year." Qin Tao complained again.

   "This is also for the navy. The navy also needs a large number of transport aircraft. If we can develop our own transport aircraft, then the navy and air force will be able to equip them in large quantities." Elder Lin said with a smile.

   "Then try to finish these things before the Spring Festival. I first need to go to the 603 and go there with the experts."

  Qin Tao can help get information, but he is a shipbuilder after all and doesn't know much about aircraft building, so he has to bring experts with him.

  A heavy snowfall a few days ago made the whole land covered in silver. Chen Lao stood in the snow with a smile to welcome Qin Tao's arrival.

   "President Qin, welcome to our 603 Office for investigation." Old Chen extended his hand enthusiastically.

   "Mr. Chen, what are you doing out here at such an advanced age? Come on, let's go in quickly." Qin Tao just shook his hand politely, and hurriedly urged.

   "Boss Qin, you look down on people too much. I am an old man with a strong body." Mr. Chen was not polite, and he spoke very casually and kindly.

  Amidst the howling north wind, a group of people walked into the meeting room.

"Mr. Qin, last time at the Zhuhai Air Show, your words were overwhelming and pointed out the direction for us. Next, we have already made improvements to the Flying Leopard fighter-bomber. If we don't pursue stealth capabilities, we will Pursue the improvement of its low-altitude penetration capability." Sitting in his seat, Chen Lao continued to speak.

   "Actually, we also need a bomber with stealth capabilities, but we must develop a new one, and we must not improve on the basis of the existing Flying Leopard fighter-bomber."

Qin Tao's words immediately heated up the atmosphere at the scene. A middle-aged man in his 30s and 40s asked, "Mr. Qin, what kind of stealth bomber do we need? Is it like the F-117? The bomb-carrying capability of our J-31A fighter jet is almost the same as this kind of aircraft, right?"

   The built-in pylons of the J-31A cannot carry too many weapons and equipment, but it is not a problem to load two bombs, and the F-117 is only at this level.

"Of course not. Although the F-117 has a prefix of F, it is actually an out-and-out attack aircraft. We are talking about bombers now." Qin Tao said: "It is the same as the American B-2 stealth bomber. Same big bomber."

(A reader earlier said that B-2 was made public in 1988. The hero of East China searched for it, and he really found this news, but I am a little curious, how could the Yankees have such a strategic killer so early? To be public, it looks like it was only enlisted in 1989, are the Yankees so impatient?)

After the B-2 bomber was made public, it almost caused a sensation all over the world. Although some aircraft designers studied the flying wing layout during World War II, until modern times, there has never been such an aircraft that has been finalized for service. In particular, this The new bomber also canceled the vertical tail, so many aircraft designers felt that it was impossible for this aircraft to fly.

   Now, when Qin Tao mentioned this bomber, everyone took a deep breath. This technological leap is too great.

   "Of course, this is the direction of future efforts. We don't need this kind of bomber yet."

  B-2 is a strategic bomber. It can fly around the world when it is deployed at a base in its own country. It can bomb any country and then fly back. At present, the Eastern policy is still defensive, so there is no need for such a big killer.

   At this time, when they heard Qin Tao say this, everyone nodded. If they were asked to develop this kind of aircraft, it would indeed be too difficult, and it would be impossible to overcome it in a short time.

   This can be a development direction in the future, but don't think so much now.

"Now, let's talk about the transport plane. This is the big guy that the Air Force urgently needs. I plan to go to the Chkalov Aircraft Factory this time. I need someone to accompany me." Qin Tao said: " I don't know if any of you are free?"

At present, the 603 Institute is still working tirelessly on the project of the Flying Leopard fighter-bomber. As far as the large transport aircraft of the Il-76 level is concerned, there is not much strength involved. At this time, after hearing what Qin Tao said, Mr. Chen said: "Xiao Tang has been engaged in the pre-research of this project, you can take him there."

   "Yes, Mr. Qin, I am willing to go with you." said the middle-aged man who spoke just now.

  He is already thirty or forty years old, but in Chen Lao's mouth, he still called Xiao Tang one by one, and Qin Tao also felt a little funny.

  Tang Changhong, born in 1959, and in 1978, he became a third-year college student who resumed the college entrance examination. He studied aerodynamics at Northwestern Polytechnical University. Yang Wei, who is currently emerging in 611, is his roommate in the upper and lower bunks. Afterwards, he entered the 603 Institute as a professional team leader. During this period, he went to the Capital University of Aeronautics and Astronautics to study solid mechanics and obtained a master's degree after graduation. After it came out, it once cooperated with the German MBB company MPC-75 project technology. In 1992, he became the deputy director of the 603 Research Institute, and now he has become the director. He is Chen Lao's close assistant and has also contributed a lot to the research and development of the Flying Leopard fighter-bomber.

Mr. Chen always trained him as his successor. Next, the Air Force is going to enter the large aircraft project. He hopes that Tang Changhong can take the lead in this project and be the leader. If this is the case, Tang Changhong will also become the youngest aircraft in China chief teacher.

   Tang Changhong is not tall, slightly fat, with a calm smile on his face.

   "I heard that you have conducted pre-research, what achievements have you made in the past few years?" Qin Tao asked.

"One of the most important research and development achievements is the supercritical airfoil." Tang Changhong said: "At present, we are already pre-researching this airfoil. The best choice comes."

  There is a big difference between military transport aircraft and civil aviation passenger aircraft. The most important indicator of civil aviation passenger aircraft is fuel economy. For civil aviation companies, fuel saving means saving money. The next step is the number of crew members. If you can use a two-person crew, you don’t need a three-person crew, which can save the cost of one crew member.

For military transport aircraft, fuel economy is the second priority. After all, the army is not afraid of fuel consumption. Their aircraft must first ensure large load capacity and long range, and the second is flight speed. To increase speed, not only must have advanced powerful engines , also need to have suitable wings.

   "Supercritical airfoil" was first developed by NASA Langley Research Center in the 1960s. It was first published publicly in 1974. Aircraft designers from all over the world have highly praised this airfoil. The most advanced C-17 transport aircraft in the United States has adopted this airfoil. At the same time, civilian airliners such as Boeing and Airbus have also begun to use this airfoil. This airfoil improves the cruising efficiency and economy of the airliner.

   Because of its advanced performance, this supercritical airfoil is even called two major breakthroughs in aerodynamics in the 20th century together with the swept wing.

Of course, this kind of airfoil cannot be made just based on a few documents, it must go through a lot of wind tunnel experiments, and it needs to be combined with the aircraft. This kind of airfoil of Yun-20 has also gone through hard work It was made with hard work.

  Its upper airfoil is relatively flat, but the lower airfoil has a concave design, and the trailing edge of the wing also has a larger and thinner curvature. The benefit of doing so is to increase the flight speed and reduce the weight of the wing structure.

  General airfoil design, when the flight speed is close to the speed of sound, shock waves will be generated on the wings, which will increase the resistance of the aircraft, which will not only cause the fuselage to vibrate and cause safety hazards, but also lead to a huge increase in fuel consumption. The amount of shock wave generated by this unique "supercritical airfoil" will not only be smaller, but also the position will be very rearward, so as to avoid the vibration of the fuselage caused by the shock wave and achieve the purpose of saving fuel.

  So, although the Yun-20 is similar to the Il-76 in appearance, there are still many differences in fact. The airfoils are different, so they can be classified as two different aircraft.

Hearing Tang Changhong's introduction, Qin Tao nodded: "That's right, we have to keep up with the world's advanced level and make our own unique aircraft. Our future domestic early warning aircraft, aerial refueling aircraft, electronic warfare aircraft, etc., all rely on It's on you!"

   "We will definitely go all out!" Tang Changhong said excitedly.

Qin Tao is also a little emotional, he is obviously not from the Air Force, but he said this, but moved the people present, of course, he is also clear about the reason, after all, no one will lose the chain after passing through the project at hand .

   Now that he is helping to contact this large aircraft project, everyone is of course very excited, which means that the large aircraft project will be launched soon, and there will be a brilliant future in the end.

"President Qin, regarding the engine, your suggestion from the Air Force is very pertinent." Mr. Chen continued to talk about the specific technology: "At present, our country is still lagging behind in engines, and our Flying Leopard fighter-bomber , relying on the mature Spey engine. Now, it is a correct choice for our big aircraft to use Lao Maozi’s D-30K engine first.”

  Hearing what Mr. Chen said, Qin Tao suddenly thought of something: "Mr. Chen, have we completed the full localization of Spey?"

The localization of Spey also experienced some twists and turns. On December 13, 1975, the import contract of Spey was officially signed. Produce an engine of the same quality level as that of the UK; within 5 years, use domestic materials, blanks, finished products and accessories to reproduce an engine that meets the above requirements.

  After entering the 1980s, the goal of the first stage was finally completed, but then it came to an abrupt end.

  Since the introduction of Spey, there have been many criticisms. This kind of British engine in the 1960s is outdated, and what is needed in China is a high-thrust engine and so on.

  At the beginning, the Flying Leopard project was established to solve the problem of Spey engines in stock. Now, seeing that the Flying Leopard has been finalized and is about to be equipped with troops, the engine is another big problem. If the domestic imitation cannot be produced, then you can only go to the UK to purchase second-hand Spey!

"Yes, the localization of Spey is a big problem." Mr. Chen said with emotion: "As our Flying Leopard began to fly, the problem of Spey's engine also became prominent, and our brother factory continued to start Spey. The localization plan is to use our own domestically produced blanks to manufacture the domestically produced turbofan nine engines. Last year, this engine passed a 150-hour endurance test run, and the localization rate was 70%."

  Qin Tao couldn't help shaking his head: "This is still far away!"

  Even if the localization rate is 99%, it may be stuck by the remaining 1%, let alone the current localization rate is only 70%! When he was working on gas turbines for ships, Qin Tao once met the technicians of Factory 430, and he drew a big cake for them at that time. The demand for this kind of engine is at least 500 units, and localization is a must!

  Who would have thought, it still doesn't work.

"At present, we have been able to stably produce WS-15 engines." Qin Tao thought of something, and continued: "In many engine processes, we have reached the world's advanced level, and the remaining 30% of the parts, If the original craftsmanship of the British cannot be figured out, can it be manufactured with our existing craftsmanship?"

   "That's right, Mr. Qin, your suggestion is very good, and we will report it to Factory 430." Mr. Chen fully agreed with Qin Tao's suggestion.

  Spey is the technology of the British in the 1960s, and the turbofan-15 is the technology of Lao Maozi in the 1980s. This kind of replacement by our side should not cause any major problems, and it can even make the performance of Spey more advanced.

   PS: Happy New Year everyone! Thanks to l599xl, book friends 20181028124729361, Xuanhuan Dadi and other friends for their rewards, thank you all book friends for subscribing and voting, and continue to ask for double monthly tickets!

  

  

  (end of this chapter)