Back in 1978, I was admitted to Northwestern Polytechnical University.

Chapter 397 What should a fourth-generation fighter jet look like? 4S!
On the high ocean, the Enterprise carrier strike group.

"What? These Indians actually accused us of bombing their nuclear base?" Captain Itville said angrily. "What are these Indians thinking? Do they think the United States is so easily framed?"

“That’s right!” Carrier Air Wing Commander Milgate also looked grim. “Since they’re so ungrateful, I think we can send a carrier air squadron to fly near their coastline. The U.S. Navy has the right to freedom of flight all over the world!”

"That's right, so what are we waiting for!"

Steam filled the deck as Tomcat fighters were launched into the air. Soon, eight Tomcats gathered together, forming a large formation, and flew towards the Indian coastline.

Soon, alarms sounded at the Indian air defense radar station. They had missed the opportunity to fight before for various reasons, but this time they would not do it again, and they quickly reported the situation up the chain of command.

The capital of India.

They just had a falling out with American diplomats, and all the Indian officials are furious. They're so angry they're about to explode when they hear that American warplanes have flown over again.

"Damn it, they dare to come again? Our Indian Air Force isn't to be trifled with either, scramble our strongest fighter jets immediately!"

"That's right, another batch of MiG-29s has arrived. Take off immediately to intercept the US Air Force!"

Mrs. Gandhi's face darkened. She pondered for a full minute before nodding: "Alright, take off, MiG-29s. However, note that our pilots are strictly ordered not to fire first!"

"Yes!"

A certain air force base in western India.

"We...we've only just started conversion training, we're not capable of carrying out combat missions at all!" Upon hearing this, the Indian pilot immediately gave up.

Are you kidding me? Sending us rookies to fight the US Navy? That's suicide! No way, absolutely not!
They looked at the Soviet advisors with expectant eyes.

The advisors shook their heads: "We're here to train pilots; we won't get involved in any conflict..."

So the order was issued to the air force base, but no one carried it out!
The American Tomcat fighter jets flew 12 nautical miles from the Indian coastline, and the Indians on the other side did not react at all. They flew for more than half an hour before finally returning to base, satisfied.

Hmph, you Indians, this time we'll teach you a lesson and show you that the mighty U.S. Navy won't tolerate anyone trying to cause trouble!
Siam, the capital.

"You are all heroes of Siam! Your deeds may be unknown to others, but your achievements will live on forever!" King Bhumibol looked at the spirited pilots one by one, and finally his gaze fell on Maha, his face full of pride.

He has been king since 1950 and has been king for thirty years. To be honest, he is getting a little tired of it. Now, his son is doing very well and has made great contributions to the country. He is considering abdicating early and handing the country over to his son.

Little did he know that his son, who was currently interested in flying, would become interested in beautiful women in a few years. At that point, he would have no choice but to continue being king. In the end, he reigned for sixty or seventy years, becoming the longest-reigning king in Siamese history.

"I am willing to serve my country!"

"Yes, everyone involved in this mission will receive a year's salary as a bonus! Our men will also be promoted two ranks!"

The people below were excited. This reward was absolutely too high. Not to mention the money, even just one promotion in rank required a lot of effort!
The King then looked at Qin Liang and his wife: "Qin, thank you for your contributions to Siam! From now on, the Pacific Trading Group will be our most respected guest. If you encounter any problems while doing business here, you can come directly to me!"

"Thank you, Your Majesty!" Yang Duo'er's face was full of smiles. Through Siam, the influence could spread to the surrounding countries, and the Southeast Asian market could be opened up!
"Your Majesty, the matter here has come to an end, and we should return now."

This trip will last quite a while! In the blink of an eye, it's already May 1983. It must be getting hotter and hotter here. It's time to go back!
"Yes, Mr. Qin, you are welcome to visit Siam anytime. You are our best friend!" the King said. "By the way, do you have any suggestions regarding our military equipment?"

"Your army and air force are sufficient now, but your naval power is too weak. Our neighbor India has an aircraft carrier." Qin Liang was instantly delighted.

Now, Siam and India are considered sworn enemies, the kind of mortal enemies. India has an aircraft carrier, so the Siamese navy needs to have one too!
Historically, Siam had purchased an aircraft carrier, built by Spain. After its purchase, it was almost never used, proving to be utterly useless. This painful experience demonstrates that smaller displacement is not always better for an aircraft carrier.

“Yes, we must develop our naval power.” The king nodded. “Do you in the East… have suitable warships?”

"Of course, we have already started construction on advanced air defense destroyers and also have suitable air defense frigates. As for aircraft carriers... although we have never built one, we have the relevant technology. If you need one, we can bring the blueprints to bid at any time."

"Okay, we will study the naval equipment issue and notify you to bid as soon as the procurement period begins!"

With all the groundwork laid, the King of Siam hosted a banquet for Qin Liang and his entourage that day. After a hearty meal, Qin Liang and his wife boarded a commercial airliner and returned to the capital of their homeland in the afternoon.

The original plan was to take a passenger plane from the capital back to Chang'an, but unexpectedly, as soon as they got off the plane, Lin Lao's secretary was waiting for them at the airport. So, they had no choice but to take a car to the airport terminal.

"Haha, Liangzi, you did a great job!" Old Lin was beaming with excitement. "The Indian nuclear base is now completely destroyed. In particular, a large number of nuclear experts are gone. For the next twenty years, India will never have a nuclear bomb again!"

Qin Liang said somewhat helplessly, "Old Lin, there's no need for such praise. This was agreed upon by the capital. Without your approval, I wouldn't dare to carry out this operation. Is there anything else?"

"Hey kid, what's wrong with praising you a bit? Everyone's been praising you these past few days... Okay, let's get to the specifics. The trainer jet your Northwestern Polytechnical University designed is basically finished, and the engine upgrade has passed long-term test runs..."

"So fast? This means our Q-5 has a reliable engine now!" Qin Liang exclaimed with great emotion. "So, is the Air Force planning to replace them in large quantities?"

Old Lin nodded: "Such a good aircraft, of course we should equip ourselves with it. Also, our air force plans to equip itself with this trainer aircraft to train pilots. It's quite good. As we gradually transition to the level of third-generation aircraft, we need advanced advanced trainer aircraft. This aircraft is simply tailor-made for us!"

Qin Liang nodded: "Yes, Elder Lin, then we've gotten a great deal again, since we didn't have to pay a single penny for research and development... Is there anything else?"

"What's the rush, kid? Your wife has already gone to her mother's house and she's definitely not coming back tonight. You just stay here quietly!"

"Anything else?"

"The J-9's test flights are progressing smoothly, and it's about to be finalized and put into service, so..."

"Is the Air Force going to start developing a fourth-generation fighter jet?"

“That’s right!” Old Lin nodded. “We believe that all the conditions are now in place. Since we have already caught up with the world’s advanced level in third-generation fighter jets, we should of course surpass them in fourth-generation fighter jets! We know that the Americans are also developing fourth-generation fighter jets. Now, we are on the same starting line as the Americans. With the help of Northwestern Polytechnical University, our progress in developing fourth-generation fighter jets will certainly be faster than that of the United States!”

"So the Air Force is going to put out a tender now?"

"It's not the right time yet. After all, no one knows what the standards for fourth-generation fighters should be," said Old Lin. "We are currently working on the standards for fourth-generation fighters. Your return is just in time to help us reach a consensus."

"Ok."

"Let's go to the conference room!"

Before he even reached the conference room, Qin Liang could hear a commotion coming from inside.

"So far, the advantages of stealth have not been tested in actual combat. We always believe that maneuverability is the most important thing! What is the key theory of third-generation fighters? It is the theory of energy-maneuverable air combat. In the field of fourth-generation fighters, we believe that maneuverability is still important!"

"The stealth capability hasn't been tested yet because we've already reached the pinnacle of the world. Before, we only needed to follow others; now, we need to research and figure it out ourselves. Back then, Comrade Qin Liang had only been at Northwestern Polytechnical University for a short time when he used stealth technology to fool the Americans. As it turns out, the Americans were very impressed, which shows that this technology is the future trend. We are now researching fourth-generation fighters not to catch up with the West, but to surpass the West and stand on the same starting line as them. If we wait until stealth technology has demonstrated its power on the battlefield before we start researching it, it will be too late!"

It can be heard that they are mainly divided into two factions: one believes that maneuverability is important, and the other believes that stealth is important. However, judging from the voices... it seems that Elder Song and Elder Lu are arguing. What about the Northern Institute, which is proud of being the largest military aircraft institute in China? They... don't seem to have spoken.

Qin Liang went inside and, sure enough, saw two groups arguing, while the Northern Institute had completely become a spectator.

The leader of the team, Old Gu, was completely bewildered. After all, neither stealth nor maneuverability were areas where the North excelled. So far, the only thing they could boast about was the J-8 high-altitude, high-speed fighter jet.

What did they say? High altitude and high speed are the only way?
Sure enough, just as Qin Liang went in, Old Master Gu spoke.

"We believe that high altitude and high speed are not outdated. The higher these indicators are, the greater the initial energy we can use to launch weapons..."

However, his voice was not loud and was almost inaudible amidst the other arguments.

"Alright, enough talk. Now, everyone, let's give Comrade Qin Liang a round of applause!"

Qin Liang is here?

Everyone stopped arguing, looked at Qin Liang, and then enthusiastic applause rang out.

"Come on, Liangzi, sit here!"

"Comrade Qin Liang, tell us, how exactly should we determine the specifications for this fourth-generation fighter jet?"

"Well, to put it simply, it's 4S."

"what?"

"First, the first 'S' stands for Stealth, which is a crucial standard that distinguishes it from previous fighter jets," Qin Liang explained. "Without a stealthy shape, we won't be able to show our aircraft to the world. We need to adopt a special design to reduce the radar cross-section and lower the probability of being detected by enemy radar. Our specifications don't need to be too high; a frontal RCS of 0.01 square meters is sufficient."

"what?"

"In other words, if we fly head-on to the enemy's radar, our fighter jets will appear to be about the size of a golf ball... or a ping-pong ball."

"How can this be!"

Everyone was stunned.

How could a ping-pong ball possibly be discovered?

Qin Liang smiled.

Most reports state that the J-20's stealth capability is 0.01 square meters, which is comparable to the F-22. As for the dedicated F-117, it is said to be an order of magnitude lower, reaching a radar cross-section of 0.001 square meters.

Let's not aim for that high; 0.01 square meters is enough.

"Okay, let me introduce the second ability, Super Sonic Cruise, which allows you to fly at supersonic speeds without using afterburner, and ideally, even up to Mach 1.4."

If you're just over the speed of sound, say only Mach 1.1, it doesn't really make much sense. When you need to rush to the battlefield, you still have to use afterburner to reach Mach 1.4 to speed up quickly and efficiently!
Finally, Old Master Lu smiled.

This requires a powerful engine, which is precisely where China is weak.

If the engine is not powerful enough, it has to be pneumatically powered. In this respect, Factory 320 has a natural advantage. After all, their current twin-engine Q6 can meet this standard!

"Thirdly, there's Super Maneuverability. This kind of aircraft must possess exceptional maneuverability. For example, its minimum turning radius should be less than 500 meters, ideally reaching 300 meters. Moreover, it should be able to quickly pitch up and point towards its target..."

Everyone fell silent. This...this seems to be beyond our capabilities!
"Finally, there's Superior Avionics for Battle Awareness and Effectiveness, which means superior information awareness capabilities. This requires advanced avionics systems to solve. For example, the nose needs to use an advanced phased array radar, and it also needs to be paired with a top-notch data link..."

"We can leave this last function to Northwestern Polytechnical University; we don't need to worry about it. But the first few performance aspects are giving us a bit of a headache!" Old Lin began, "For example, the second and third ones both require powerful engines, and currently..."

Currently, China's aero-engine technology is also making rapid progress. Rolls-Royce's three-rotor engine has been put into production, and various advanced raw materials and processing technologies are being mastered gradually. However, high-thrust engines are still under development, and this path is not easy to take.

Currently, China still mainly uses the WP-15 turbojet engine. Is this engine not only the mainstay of third-generation aircraft, but also to be used in fourth-generation aircraft?

"Yes, currently, the engine is indeed our weakness. We can't rush this. If we can't achieve the supersonic cruise capability, we can put it aside for now and replace it with a brand new engine when we have one. Just like now, the Q-5 has been used for many years, and only now do we have an advanced engine."

Old Lin nodded: "That's right!"

"However, super maneuverability must be achieved, which is mainly achieved through engine vector propulsion technology. We can experiment on existing engines, and when we have new engines in the future, we can replace the nozzles and upgrade the program."

If you want super maneuverability, then vector propulsion technology is a must!
"This thing... I'm afraid there isn't one like it anywhere in the world!" someone doubted.

“That’s right. If we don’t have it in the whole world, we have to be the first. We can’t always be following in other people’s footsteps,” Qin Liang said. “This vector nozzle has two types. One is two-dimensional, which swings up and down. This structure is simple and good for stealth, but it’s not the best for maneuverability. The other is three-dimensional, which can swing up, down, left, and right. This has the greatest effect on improving maneuverability, but it has a complex structure and a high failure rate…”

Everyone's eyes widened. It turned out that Northwestern Polytechnical University already had this technology. So what were they waiting for? Anyway, they were all OEMs, not engine manufacturers. They could just hand it over to the supporting factories!
What Qin Liang was referring to were naturally the two types that are commonly seen in later generations.

The Russians have an obsessive pursuit of maneuverability, so they use three-dimensional nozzles, or omnidirectional nozzles. They performed dazzling maneuvers at air shows, which drew praise from the audience. But what good are they in actual combat?
Indians are the most qualified to speak on this. They used this advanced technology, only to find out that the vector nozzle's lifespan was a mere fifteen hours!
The two-dimensional nozzle used on the F-22 is mature and reliable. Later, when our J-20 was upgraded with the WS-15 turbofan engine, the upgraded nozzle also used this technology.

"Yes, this technology should also be handed over to Northwestern Polytechnical University!" Professor Lin nodded.

Qin Liang said helplessly, "Professor Lin, if we're going to leave everything to Northwestern Polytechnical University, why bother finding other manufacturers to bid? Let's just let Northwestern Polytechnical University take over the contract!"

Originally, everyone was still arguing, but now, after hearing Qin Liang's explanation, it seems they have the technological reserves. Even this stealth capability is from Northwestern Polytechnical University; they were selling it to the Americans, but they've been researching it themselves, so…

"Professor Lin, should this research and development project be led by Northwestern Polytechnical University? Let them take the lead, and we'll handle the sub-systems?"

Qin Liang opened his eyes wide and looked at the person who spoke.

Old Gu?
You...

Well, this does indeed meet the needs of the Northern Institute. The Northern Institute can't come up with any advanced solutions. Rather than being isolated and marginalized, they might as well follow in Northwestern Polytechnical University's footsteps and get a few scraps of soup.

Old Lin also looked at Qin Liang: "Liangzi, what do you think?"
Qin Liang shook his head: "No, no, that won't do. Northwestern Polytechnical University has some advanced aspects, but when it comes to professional technology, we still can't compare with our various research institutes and manufacturing plants. At most, we can provide some technical consulting support; we won't take on all the work."

Qin Liang looked at Elder Lin: "Now, our country has a wealth of talent and strong research institutes. I think we can totally do what the West does and select the strongest fighter jet through bidding!"

　PS: The previous picture shows a two-dimensional nozzle, where the left and right baffles are stationary, while the top and bottom baffles move. The one below is a three-dimensional vector nozzle, with many actuators at the tail that control the movement of the fence-like nozzles, which can swing up, down, left, and right.

　　
　
(End of this chapter)