"Papaya, why did you come so early today, I usually have theory classes in the aviation school, but I have never seen you so active, what's the matter, the sun is coming out in the west?"

As soon as he put down the book in his hand, before the stool could be pulled out, Chen Tiancai turned his head and caught a glimpse of his best friend already studying his homework in the seat, and his jaw almost dropped.

Time flies quickly, and the end of 1917 came in a flash, and the cause of the school engineering team and the aviation school has gradually moved on the right track.

In addition to some necessary physical fitness classes, the students of the aviation school and the members of the school engineering team have been selected, and the usual training is gradually separated.

However, while training pilots and escorts, Cheng Nuo also deliberately used his connections and fame from various universities in Beijing and Tianjin to find a group of relatively good seedlings to train flight designers.

Considering that some members of the school engineering team were not selected as flight designers, but still had a great interest in aircraft, after soliciting their opinions, a group of people were recruited to be converted into ground crew, and some mechanical courses were also taken.

And Chen Tiancai and Xia Sigui, who were in the same batch, were hired as ground crews.

"Look what kind of nonsense you are talking about, today is the dean in person, who dares not to come early, I think I am tired of being alive, I have to sit in the first row if you come late, I know what it means, it means that the dean will personally ask you." Xia Sigui just glanced at his friend, and quickly turned his gaze back to the book.

"Hey, you almost forgot if you didn't say it, for the sake of insurance, I'd better take a second look, I passed by in the last material class assessment, and I can't hang it like this anymore." The more Chen Tiancai thought about it, the more frightened he became, he sat down on the chair and began to read the book.

In fact, it's no wonder that they are so cowardly, first, they are from the bottom, and it is already very remarkable that they can write their names in their hometowns, and now they directly cross several thresholds to learn this kind of knowledge, purely by rote memorization, as for understanding and using things, they have to be delayed.

Second, the "Aircraft Materials" course taught by Cheng Nuo is considered a cutting-edge subject in today's world, and it is difficult for insiders to learn it, not to mention laymen like the two of them.

So, during the time when the class bell had not yet rang, the classroom was surprisingly quiet, especially the students who came late and sat in the front row, some of them were so nervous that they kept sweating, and they wiped their hands over and over again, and they couldn't finish wiping them at all.

"Zhang San, you take it slowly, lend me the notes from last time, I'm good at drawing the key points, don't ask me questions in a while."

"Why don't you read Li Si's notes, last time he remembered quickly and completely, I didn't remember so much at all."

"That guy's font is like a hemp shrimp dancing, the ghost talisman of the old king in the village is learned from him, who can know, last time I pointed to a sentence he wrote and asked him for a long time, he looked at it himself for a long time, and finally told me that he didn't know what to write, you tell me about it......"

"Wang Er, behind the back is called chewing people's tongues, that's not authentic, don't borrow my things next time, I'll get in the way of your eyes again!"

Seeing that several people were about to quarrel, a young man in a robe suddenly walked over from outside the classroom, carrying a thick pile of copywriting in his hand.

Seeing this person come in, the classroom immediately fell silent, except for a few people who were bold enough to look at this person, the rest of the students buried their heads in their textbooks, for fear of making eye contact with this person.

"Stand up!"

"Good morning, teacher!"

"You may be seated, good morning!"

As the class bell rang, Cheng Nuo stood in front of the lectern and waved his hand to everyone, with an inexplicable smile on his face: "Students, I told you in the first class that as a student, you must not only learn the knowledge in the textbook, but also always pay attention to the changes around you.

Recently, a big event happened around us, is there anyone willing to answer it? ”

Perhaps because of Cheng Nuo's prestige, none of the students below were willing to get up and answer the question, even though it seemed so simple.

Cheng Nuo had expected this, stretched out his index finger and said: "Those who answer the question will be given 10 points as usual!" ”

After listening, some students couldn't resist the temptation of their usual minutes and hurriedly raised their hands.

If you don't know, put it aside, and then think about it after standing up, mainly because it's too fragrant to usually score 10 points.

Because Cheng Nuo said in the first class, the final score = usual score + mid-term grade + final grade, adjusted according to the corresponding proportion, so the quality of the usual score is related to the level of undergraduate grades.

"Sir, I have an idea." With permission, a tall, lanky man stood up and replied.

"Oh, then you talk about it, don't be nervous, because you are the first person willing to answer this question, whether the result is right or wrong, this will be added to you, of course, there is no right or wrong in objective facts, you can boldly say it." Cheng Nuo stepped down from the podium and stood beside the man and encouraged.

"That's right, I prefer to read newspapers, recently "Declaration", "Times", "Morning Bell" began to report on our northern neighbor Da Mao's Red Revolution, although the evaluation is different, but in my opinion, it is not at all inferior to the three people's ...... proposed by Mr. Sun" Speaking of this, the student's eyes could not hide their fanaticism.

However, some things are not suitable for being said in public, for the sake of the students and everyone, Cheng Nuo hurriedly stopped the students.

"This matter is not as simple as you think, we will have a chance to talk about it later."

Patting the student's shoulder to sit down, Cheng Nuo thought for a moment and walked towards the center of the classroom: "In this way, I will limit the scope of application, about this school, or the same as just now, the first person to answer the question, whether it is right or wrong, usually adds 10 points." ”

Although the scope of application has been increased, there is an example of the students in the front, and the students who raise their hands to answer in the back are more unscrupulous.

Afraid that Cheng Nuo would not see the students in the back row, Chen Tiancai stood up directly: "I heard from other teachers that our school was originally established to help victims like us, and it just happened that a few days ago I heard that the government borrowed 5 million yen from Japan, saying that it would be used for post-disaster reconstruction.

Does this meet the requirements of Mr.? ”

Cheng Nuo sighed silently in his heart, there are not too many things to divide into three or seven, but I don't know what I sold again.

But obviously these things are not what Cheng Nuo wants to know, society is cruel enough, and he doesn't want the students to know about these things for the time being.

Maybe the time was not yet ripe, Cheng Nuo thought about it or forgot it, and walked back to the podium.

"Okay, it seems that you don't know much about what happened at our aviation school for the time being, but it's coming soon, and it won't be long before you can see it. Let's officially enter the class time, first of all, according to the usual practice, I will first find a few students to answer the homework assigned after the last class, then start from the first row.

First of all, why don't you use traditional metal for the landing gear? ”

"Uh...... This one...... This is because the main landing gear of the aircraft bears the impact force of tens or even hundreds of tons of force at the moment of landing, so it is necessary to use ultra-high-strength structural steel with good impact toughness......"

In this way, a few questions continued, and the students were like lambs waiting to be slaughtered, trembling in place.

Of course, designing an aircraft is not simply a matter of throwing out the theory, and even if Cheng Nuo hands over the design drawings, it cannot be completely imitated.

In particular, the aircraft will be subjected to a large external force during take-off, ascent, high-speed operation and landing, and the force on each part of the aircraft is also different, so its mechanical properties must meet the standard.

In the same way, the aircraft is subjected to harsh climatic conditions in flight, industrial pollution, salt spray, atmospheric relative temperature, humidity, flight altitude, range, runway conditions, coolant, fuel, hydraulic oil, battery fluid, etc.

However, due to the effect of the earth's gravity and air resistance, the lighter the aircraft, the better, so the aircraft needs light metals. The lighter the aircraft, the higher, farther, faster, and more loaded it will be, and the lower the fuel consumption, thus increasing the economic impact on society and nature.

The combination of various factors, even with a prescient plug-in, does not guarantee that the aircraft will be able to complete the construction of the prototype as soon as possible.

Just when Cheng Nuo finished class and just entered his office to rest, there was a commotion from outside.

"Listen, is this the sound of a dragon?"

"Hiss~ I've never heard this sound before, it really looks like a dragon's groan."

"What kind of dragon and phoenix cry, you take a good look at whether this is an airplane, it doesn't matter if the students of our school engineering team don't know each other, and the students of your aviation school don't know either, isn't it a joke?"

"I remember that the plane at Nanyuan Airport didn't fly like this, and the sound was not so loud."

"Don't you look at it, this plane is much stronger than those antique goods in Nanyuan, the shape is far worse than that, in my opinion, appearance is one of the experience standards of aircraft combat effectiveness, a good-looking aircraft, the ability will not be bad."

……

One by one, the students raised their heads and tried their best to look at the plane in the sky.

It's a pity that no matter what you say, no one wants to believe that it is a domestic plane, and when the plane lands safely and the pilot comes out of the airport safely, it is still unbelievable.

Even Cheng Nuo is one of the fools.

But now that such a big event has happened, Cheng Nuo, as the principal, of course has to rush to the scene as soon as possible.

When the pilot over there saw Cheng Nuo coming, he saluted directly: "Dean, fortunately, the F-1 monoplane all-metal prototype has successfully flown successfully!" ”

Hearing this, Cheng Nuo immediately felt a little confused, he couldn't imagine that the other party would come to such a show, and he didn't know the specific situation about the test flight for the time being, just like other students.

Just as he was thinking about how to settle the other party, Ba Yuzao and Wang Zhu squeezed directly into the crowd and told all this.

It turned out that after getting Cheng Nuo's improvement suggestions, they went back and immediately worked overtime to demonstrate, and the data calculated on paper proved that the improved aircraft had better performance and greater safety.

At this point, they began to work overtime day and night, and the prototype was built in a few months.

However, because it is a rare monoplane, and it is also an all-metal structure, let alone ordinary pilots, even if the old test pilot takes it out alone, standing in front of this F-1 aircraft, his heart is hairy.

Even if they look closely, they can find that there are still many unpolished rivets on this plane, and the safety of the plane is really not much guaranteed.

However, seeing that the plane had landed smoothly, Cheng Nuo's heart hanging in mid-air dropped a lot, but his face was still very serious: "Next time there is such a major project, you must notify me in advance, it is acceptable to make mistakes, but cheating is not the way of our academy." ”

Ba Yuzao repeatedly promised: "Don't take it as an example!" ”

However, now is obviously not the time to talk about business, Cheng Nuo returned to the office, took out the improved aircraft design drawings of the two, and looked at them seriously.

With a number of excellent aircraft in front of it, the design of the F-1 has been quite complete by that time, and the structure, materials, wings, lifting devices, instruments, engines, etc., all have clear data support, and it looks quite good.

However, after many days of study, Cheng Nuo still found some problems.

"Are you sure you use curved airfoil blocks for this aircraft?" Cheng Nuo picked up the pencil, circled the wings of the plane and asked.

At the beginning of the invention of the airplane, designers studied and designed the wings mainly based on the shape of the bird's wings. From Lilinthal to Phillips to the Wright brothers, the airfoils used were thin, arched double-curved airfoils like bird wings.

In particular, with regard to the relationship between airfoil and lift and drag, it was believed that bending the airfoil was advantageous for generating large lift.

The smile on Ba Yuzao's face gradually faded: "The specific parameters are obtained according to the wind tunnel test, and the current aircraft all use thin airfoils with curves. ”

Cheng Nuo smiled and shook his head: "Yes, although the airfoil of this type can produce a large lift, the drag is also very large, so the wing lift resistance is relatively low." ”

Wang Zhu seemed to understand: "In other words, there is further room for the F-1 prototype to rise?" ”

Cheng Nuo threw the pencil on the paper and smiled: "Of course, it is better to use the lift resistance characteristics of the wing with a relatively large thickness than the thin airfoil, and obtain a higher lift coefficient and a lower drag coefficient......

Although the design and flight test of the new all-metal aircraft was successful, especially in the Far East, it was an epoch-making existence, and basically no aircraft could surpass the performance of the F-1.

However, advanced is only relatively speaking, and it is more of a pathfinder of the Academy of Sciences regardless of the cost, with a lot of room for improvement.

For example, innovations have been made in endurance time, cruising range, flight altitude, rocket-boosted take-off and in-flight refueling, and research has been made for passenger type, cargo type and later military type have been ordered, and then great commercial achievements have been made.

When the time comes, it will smoothly move to the military side in case of special needs in the future.

So despite the success of the F-1 test flight, Cheng Nuo still has high requirements for it.

(End of chapter)