Qian Zhonghua drove by himself and took Wang Yinan all the way forward.

"Where are we going?" asked Wang Yinan.

"You'll know when the time comes", Qian Zhonghua didn't reveal his tone at all.

Twenty minutes later, the car arrived at a military airport in the southern suburbs, and Qian Zhonghua's car drove through two sentry posts until it reached a domestically produced Yunqi that was already in operation.

Qian Zhonghua took the huge headset handed over by a female soldier dressed in the air force in front of the escalator,

In the roar of the huge engine, he handed it to Wang Yinan, then pointed to his ear and motioned for him to bring it.

Wang Yinan put on headphones and immediately heard Qian Zhonghua's voice, "Board the plane first."

"Okay, don't kidnap me", Wang Yinan and Qian Zhonghua just boarded the plane, and Yun Qi took off.

In the huge cabin, there were only two passengers, Qian Zhonghua and Wang Yinan, Qian Zhonghua picked up an umbrella bag and handed it to Wang Yinan.

Qian Zhonghua's voice came from the earphones, "Can you skydive?"

Wang Yinan shook his head blankly, "Big brother, don't scare me, are we going to fight?"

"Haha", Qian Zhonghua laughed, "Scare you", after speaking, he threw the umbrella bag aside, handed Wang Yinan a document, and a "top secret" red seal on the cover brightened Wang Yinan's eyes.

Wang Yinan shook his head, "Don't watch, don't watch, don't give me this set, I'll definitely get into big trouble after reading it."

"I can't help you when I get on the plane, anyway, this document is in my hands, and you got on the plane with me, whether you have seen it or not, in fact, it doesn't matter anymore", Qian Zhonghua said indifferently.

Wang Yinan thought of a joke he had seen, saying that a farmer raised a donkey, and one day he took the donkey to the market, and when he came back, someone set off a firecracker, and there was a "whoop". He didn't care, he led the donkey and went home.

When he got home, he threw the donkey in the shed and went to eat, but the donkey ran back to the place where the firecrackers were fired, and looked everywhere, where did the sound come from?

Wang Yinan felt that he was the donkey, and after a while, he couldn't help but open the top-secret document.

The document is about a certain model of domestic fighter jet, and as soon as he read the title, Wang Yinan couldn't help but say to Qian Zhonghua, "Are you sure, this thing can be shown to me"

"Don't worry, your current secret level is not low, if you do a good job this time, I will apply for a military rank for you when I go back."

"Seminar on the flight control system of a certain type of fighter", this is the name of the document, Wang Yinan carefully read the document.

Probably like this, in the design process of a certain type of fighter, it was expected to use the next-generation domestic engine turbofan 51, but due to the poor process of domestic turbofan blades, there are a series of process and test problems, so the finalization time of the engine has been postponed indefinitely

If there is a problem with the engine, what should I do with the plane, I can't stop and wait for the engine, then I have to wait until when to go, three years and five years are less, and ten or eight years are normal.

There was no way, so the design unit had to temporarily switch to the engine of the woolly bear.

But the fighter is a complex system engineering, there are too many aspects involved in changing the engine, first of all, the shape is different, the third aunt is longer and thinner than the turbofan 51, so the designer must first correct the shape, not simply correct the engine compartment, the overall aerodynamic shape needs to be modified accordingly.

At the same time, the weight of the two is not the same, so the entire aircraft needs to be retrimmed.

This is not the most troublesome thing, the most troublesome thing is that the thrust response curve of the engine is completely different.

For example, at what altitude, how much thrust is output, from 10 tons of thrust to 12 tons of thrust, the time required is 0.5 seconds or 0.8 seconds

The new fighter uses an all-digital fly-by-wire control system, as well as a Flying Fire integrated control system, that is, the control of each rudder surface, to the throttle size of the engine, the aiming and launching of weapons, all are controlled by computers.

What's worse is that a certain type of fighter adopts a canard aerodynamic layout, which is completely static and unstable.

What is called static instability, for example, all the control surfaces of the aircraft do not move, such as flaps, vertical tails, etc., at a certain altitude and speed, if the aircraft can maintain stable flight, then, the aircraft is statically stable.

On the contrary, if at a certain altitude and speed, it must be continuously adjusted through small movements of different control surfaces in order to maintain stable flight, it is a statically unstable aircraft.

In the era of no digital fly-by-wire flight control, all aircraft are static and stable, because static unstable aircraft require the pilot to continuously fine-tune the control surface, not to mention the possibility of mistakes, just this tense workload, not a few minutes in the sky, no matter how good the pilot will be tired and paralyzed.

However, from a combat point of view, the agility of a statically unstable aircraft, such as the radius of the maneuver and the instantaneous pointing of the nose, is definitely too much ahead of the statically stable aircraft, so modern fighters are statically unstable, using various control rates pre-programmed by the on-board computer to control the aircraft.

The pilot only needs to pass on his intentions to the on-board computer through the joystick, such as climbing, flying upside down, etc. The rest, the control of the throttle and rudder surface, is done by the on-board computer.

I have been tossing and turning for several years, and some time ago, it was said that the design unit had done it, and Wang Yinan, who is a military fan, seems to have seen something similar in a forum

The post "The first flight of the new domestic fighter was successful", as well as vague photos taken with mobile phones.

The veteran fans in the forum have been partying for a while.

However, judging from the documents, after the first flight, there was big trouble.

There were several times when the preset control rate was exceeded during the flight, in fact, the plane was suddenly out of control, and once in the process of level flight, it entered the tailspin without warning, although the pilot handled it properly and did not cause a tragic accident of plane destruction and death, but all the prototypes were forced to ground off.

Doubts about the original design began to increase, so the relevant departments at higher levels organized this seminar to conduct a comprehensive evaluation of the design of a certain type of fighter. Didn't Qian Zhonghua look for experts to ask for possible applications of the Gödel system recently? To be honest, he said it so mysteriously that most experts dismissed it.

Today, Qian Zhonghua chatted with several experts from Imperial Capital Aviation in the Ministry of Aviation Industry, and said that this seminar has been held in Shudu for two days, Qian Zhonghua pondered that his father has enough influence in the Air Force, and he and Wang Yinan can be invited experts by the Air Force to participate in the conference on behalf of the Air Force, which is also justified.

So he brought Wang Yinan here.

"Then we're going to Shudu?" Knowing the cause and effect, Wang Yinan also breathed a sigh of relief, consultant, consultant, it's normal not to ask.

"Yes".

In the midst of the strong turbulence, the plane soon landed at the Shudu Aircraft Design Institute, commonly known as the 116 own airport.

"It's a real cow, it's still an aircraft design cow, it comes with an airport, I'll ask who else", Wang Yinan is quite envious, it seems that the company will move out of the imperial capital in the future, and it will definitely be no fun to get an airport in the imperial capital, Shudu, Chang'an or something, it is estimated that it is still possible.

As soon as the escalator came up, Qian Zhonghua pulled Wang Yinan to climb down, boarded the jeep that had been waiting on the side and went straight to the conference room.

"How's it going," Qian Zhonghua asked an Air Force officer sitting in the passenger seat.

"When I came, the discussion was still very intense, but the situation was not very favorable for the 116 Institute," said the officer.

"TMD, these officers are all good at finding faults", obviously, the Air Force still prefers 116 institutes.

The jeep stopped in front of a small building, and after the guards at the entrance of the building checked their documents, the Air Force officer led them to a small conference room. The three of them entered through the back door and sat down on a few chairs by the wall.

"Judging from these two cases, the problems with the flight control system of Project XXX are not accidental"

"With such a complex aerodynamic design, the selection of control surfaces would have exceeded the existing state of the art"

"Even if there is no matter of hair replacement, I believe that the same problem will arise"

"So, the root cause of the problem is that the designers chose an overly radical aerodynamic design, which caused a series of bad consequences today"

In front of the huge conference table, there were about twenty people, most of whom were not wearing military uniforms, and they were gray-haired, not young. An old man in his early sixties spoke into the microphone.

"Who is this?" Qian Zhonghua asked the Air Force officer in a low voice.

"The chief division of a certain Hoy, when he bid for the development of this type of aircraft before, he lost to the 116 Institute, and now he has a chance," the officer pouted.

At this time, a middle-aged man interrupted him, "Old G, what you said is too arbitrary, right?"

"As a twin-engine heavy fighter, and it is the first stealth fighter in China, in the case of a major gap between our engine and the United States, and it cannot be made up for a long time, I think it is not a risk to make innovations in aerodynamic shape, but a must."

"The result of the adventure is that the flight control system is not up to par, if it weren't for the excellent quality of the pilot, you would have been destroyed and killed."

"If you don't take the risk, you will be twenty years behind the people before you go to the sky, and if you really fight in the future, you still let our soldiers fight the enemy with burning sticks?"

"You, you, who are you talking about?" looked at this posture, and saw that a fight was about to start.

"Okay, okay, we're here to solve problems, not to quarrel," the head of the assembly, who was sitting in the main seat, knocked on the table.

"Today is the third day, the opinions of all parties have been fully expounded, the meeting cannot be dragged on endlessly, and there must be a conclusion today"

"Adjourn the meeting for half an hour, continue after half an hour, vote if it doesn't work, and come up with a final plan today."

The people in the conference room dispersed in twos and threes, and the Air Force officer brought Qian Zhonghua and Wang Yinan to the middle-aged man who had just spoken.

"This is Chief Engineer Yang of the 116th Institute, and he is also the chief designer of a certain type of fighter," he told Qian Zhonghua and Wang Yinan.

"Chief Master Yang, this is Qian Zhonghua and Wang Yinan, experts invited by the Air Force."

Wang Yinan shook hands with Chief Master Yang,

"Let's not talk about it, what's the situation now?"

"What is your biggest problem at the moment, let's see if we can help"

"Now the situation is very complicated, a certain Hoy has made a traditional layout plan, and has always had his own supporters, and their goal this time is to have two plans in parallel."

"At present, our biggest problem is still in the flight control, the requirements of twin engines and stealth, plus canard wings and full motion vertical tail, these factors are close to our limits"

"Now the replacement of the engine is the last straw", "Problems are inevitable"

"Then what are you going to do?" Wang Yinan asked.

"The biggest problem now is time, even if the aerodynamic shape is not modified, to completely solve the problem of flight control, the most optimistic estimate, it will take more than a year"

"As things stand, it's hard for us to get another year."