In fact, Chang Haonan doesn't have much to talk about.

Now that the problem has been identified, the natural next step is to solve it.

Aircraft manufacturing is an extremely complex industrial process, and even more than 20 years later, many steps are still highly manual operations, and in this process, it is almost inevitable to produce some metal residues such as rivet breaks, metal chips, etc.

But under normal circumstances, firstly, according to the regulations, before the end of each step in the final assembly process, the parts should be inspected and cleaned, this step should be able to dispose of most of the foreign objects on the surface of the workpiece, and secondly, even if there are some leaky fish in some deep holes that are difficult to detect and clean, they cannot easily run into the air intake.

As for the fact that the prototype No. 1001 did not inspect and clean the inside of the air intake before delivery......

Chang Haonan glanced at the representative of the 132 factory who lowered his head and didn't even dare to come out, and felt that this possibility was probably relatively low.

With the importance of Project No. 10, all the inspection processes must be repeated many times during the final assembly process.

Besides, even if it is only logically judged, if the quality management of Factory 132 can be outrageous to this extent, then similar accidents should have happened long ago.

Thinking of this, Chang Haonan quickly went through the aircraft manufacturing process he had learned from Factory 112 in his mind, and then stood up.

As a result, before he could speak, and he didn't know who started it, there was a round of applause in the conference room.

At first, it was sparse, but almost instantaneously it became like a tide.

Chang Haonan raised his hand and pressed down, but it didn't have any effect.

He noticed that the eyes of the participants, especially those from the test station and the final assembly workshop, had changed markedly compared to the previous days and even this morning.

That's the difference between "hearing that a person is awesome" and "realizing that a person is really awesome".

It wasn't until about a minute later that the applause finally subsided.

"First of all, judging from the content of the test report, the metal chips attached to the end of the air intake tract and the engine blades can basically be determined to come from the drilling and nail pressing process during the riveting process."

Although this is a problem that everyone is aware of, when it is officially summarized at the meeting, many people's hearts still sink.

Especially Xue Chiyu.

As the chief engineer, he is inevitably responsible for such a big quality flaw in the production and manufacturing process of the prototype.

Of course, he is also mentally prepared for this.

However, just when Xue Chiyu was ready to conduct some self-criticism, Chang Haonan immediately changed his words:

"But I don't think it's a problem due to production responsibility or the lack of implementation of quality inspection rules, the main reason should be at the technical level."

This sentence instantly calmed down the hearts of many people.

"Compared with the various types of J-7 aircraft produced by Factory 132 in the past, the No. 10 project is unprecedented in the complexity of process and design, and the standard of production and testing cannot be improved overnight, that is to say, many operating processes and production regulations that were not problematic before may have problems now."

"Therefore, in view of the current situation, I think there are two tasks that should be carried out immediately, one is to conduct a thorough investigation of the aircraft, and conduct a thorough inspection of the excess objects that accidentally fell into the internal cavity of the aircraft during the skin riveting process, and the other is to comprehensively inspect the design of the aircraft and find out where the foreign objects in the internal cavity of the aircraft enter the air intake."

After a brief speech, Chang Haonan returned to his seat.

Although he was invited to serve as a consultant for Project No. 10, and his authority and voice in the project are not small, after all, he is not a person within the 611 Institute and the 132 factory, and he must not say too much about the more specific responsibility attribution.

That's a matter for their organizational department.

"I'll add two more points."

Xue Chiyu pulled the microphone in front of him slightly closer to him,

"No matter what the cause of the problem is finally investigated, the main responsibility is borne by me, so we should not have too much psychological baggage in the work, in addition, after the end of the investigation, according to the characteristics of the J-10 to formulate the corresponding production rules and regulations, to ensure that in the future in any link of production, no excess is allowed to enter the body cavity."

"Adjournment!"

After clarifying the next tasks and eating the reassuring pills fed by Xue Chiyu, the haze of the failure of the first test work was finally swept away, and everyone quickly carried out follow-up work in accordance with the deployment at the meeting.

Factory 132 turned its head and directly carried out the construction activities of a "quality culture month", not to mention, the 611 Institute here, the speed of investigation of the design of the air inlet is faster than Chang Haonan thought.

Early in the morning of the third day, he had just come to the office after breakfast, and received a call from Yang Wei:

"The connection between the air intake and the inner cavity of the body has been found."

"So fast? I'll be there right away. ”

A few minutes later, Chang Haonan found Yang Wei buried in the pile of drawings in a design room-

Since the design of Project 10 began in the early 90s, and the basic design was completed before Chang Haonan's rebirth, it was natural that he did not wait for the opportunity to use digital design technology.

Now the 611 Institute has begun to organize some people to absorb relevant experience from the 601 and 603 Institutes, but this kind of work is destined to be impossible to complete in a short period of time.

So I still have to turn the paper diagram slowly.

"Chang Gong, I confirmed several times yesterday that the J-10's air intake is not physically connected with the wings and fuselage compartments and other cavities, even if there are foreign objects remaining in these parts, it is absolutely impossible to be sucked into the air intake, so I changed my mind this morning, you see here."

Yang Wei said and pointed to several places near the entrance to the air intake.

"In order to ensure the effectiveness and reliability under various working conditions, there are several spherical one-way valves in it, and the manufacturing process of this component is to install the springs, brackets and valves inside the housing and close them directly, which belongs to a part that cannot be decomposed after being offline."

"I asked the manufacturer responsible for making the valve, and I learned that they used to use a simple kerosene flushing method to clean it, but after analysis, this method did not do a good job of removing foreign matter that may remain inside the housing."

"Under normal circumstances, this valve should close during the operation of the engine, but if something gets stuck in the bearing part, it will lead to poor reset, in this case, the strong negative pressure inside the intake is likely to suck out the metal foreign matter inside!"

Chang Haonan took a few design drawings of the air intake and the spherical one-way flap, spread them out on the table and carefully observed them for a few seconds.

Then he remembered that he had seen similar structures before.

"Wait a minute...... Shouldn't this thing have a dedicated cleaning mandrel? ”

"Dedicated mandrel?"

Yang Wei was stunned:

"They didn't mention it, they said it was a direct high-pressure fluid flushing method."

"Hmm......"

Chang Haonan realized that the cleaning tool he had seen in his previous life should have been made in the process of solving the problem after the J-10 failed two consecutive test runs.

Fortunately, the structure is not complicated, and he can easily come up with a design drawing by pushing it back on site.

"Do you have a computer here, with a drawing tool?"

"There's next door, I'll take you there."

At noon that day, Chang Haonan handed over a printed drawing to Yang Wei.

"The principle of this equipment is like that of Figure 2, before cleaning, use the mandrel shown in Figure 3 to push the valve 10 open, and then rinse with reverse pressure......"

Yang Wei listened to Chang Haonan's introduction, and the whole person stood out and was dumbfounded.

After a long time, he took the drawings from the latter's hand and said with emotion:

"I used to think that I was somewhat level in engineering."

"Now it seems that we have to continue to pursue progress......

(End of chapter)