Wang Ming looked strange when he heard Lin Yongming's request on the phone.

He could not understand why Lin Yongming, who had fully supported the introduction of Russian-made engines a month ago, suddenly changed his mind.

Moreover, the other party on the phone said that he wanted to develop his own engine, but it didn't seem to be referring to the WS-10.

Are there any new plans?

Is it too late?

Or is there an alternative in the United States?

I seem to have heard before that they have plans to share the full set of CFM56-3 engine technology with China, and even plan to provide some upgrade technologies.

But even so, there may not be enough time.

Wang Ming wanted to ask for clarification, but Lin Yongming pushed him back with the words "confidentiality regulations." The other party asked him to call back in half an hour using a confidential line, and then inform him of the details.

So, he had no choice but to hang up the phone in confusion.

"Lubrication reliability!"

"I really can't understand why the plan needs to be changed suddenly. If it is because of recent accidents, I think this reason is not sufficient."

However, what he didn't expect was that Lin Yongming did not try to use his status to persuade him, but patiently explained:

If they don't see the problem, then there is nothing wrong with the engine.

"The AL-31FN engine is good, but I want to ask you, do you know what the design concept of this engine is? What methods did they use to improve this engine when the material strength is not enough?

Motivation?"

"Generally speaking, the nozzle for injecting lubricating oil will be installed very close to the bearing in the engine, directly injecting high-pressure, large-flow lubricating oil at high speed onto the balls and roller rods of the bearing."

"This is not a question of whether it's too late, it's a question of whether it's possible. The progress of WS-10 has been so poor, and now a new project is being launched. Isn't this whimsical?"

Cold sweat broke out on his body.

"I have made an appointment with Mr. Lin and will discuss the details with him later. If I can report it then, I will report it to everyone immediately."

Although he is not an expert in this field, he still understands some basic principles.

"Leader, if you say there is a problem with AL-31FN, you must at least provide convincing evidence. Otherwise, it will be difficult for me to convince the employees below me."

It's not because of their lack of capabilities, but because the flight data is too poor to reflect the true working conditions of the lubrication system in the engine. Every time there is a problem with the engine, the Russian side will immediately take it back for inspection, without even having the opportunity to inspect it.

Those worn components!

Behind him, the purchasing representatives who stayed in the conference room were talking a lot.

"Leader, this decision is really too sudden."

"Self-developed engine? What is going on? It's a bit exaggerated. The J-10 is about to enter mass production. How can it be possible to change the engine in time?"

I really need to build an engine.

"It's very possible. Otherwise, how can you explain these three accidents? Don't we ourselves also think there is a problem? It's just that we have no choice, it's the lesser of two evils."

Wang Ming here was stunned when he heard this and said subconsciously:

After hearing Lin Yongming's words, Wang Ming on the other end of the phone fell into deep thought.

After that, Wang Ming hurriedly left the conference room.

It absolutely cannot be Lin Yongming, he does not have such a professional level.

"Are you kidding me? They can't even see it. Can anyone else in the country see the problem? Damn it, isn't this just another slap on the head decision?"

At this time, he was full of doubts, and almost didn't wait for a moment. He wanted to call the internal phone number immediately to find out what happened in the group.

Wang Ming was sitting at the table, talking on the phone with a frown on his face.

"Defects? From the current point of view, there are no obvious flaws in this design. If it must be said, it is probably because the connection method of the bearings is more complicated?"

Even if you are a leader, you must respect objective laws. You can't overturn all the judgments of professionals with just one sentence from your superiors, right?

The Su-27 is a twin-engine fighter, while the J-10 is a single-engine fighter!

No wonder the problem always occurs when the engine is under high load!

The hair on his body stood up, and his mouth opened subconsciously, but he could only stutter out a few words.

"It's because the Su-27 has twin engines."

"So, the lubrication system is particularly important for this engine."

"But even so, it would not be wise to rashly stop the introduction of AL-31FN. We should at least purchase a small amount and spend the window period first."

"In short, let's postpone the plan to the second round of negotiations next week."

Wang Ming replied without hesitation.

Could it be that some old monster has come out again?

"What if the AL-31FN simply has a major flaw?"

"We'll build a brand new engine."

Wang Ming nodded numbly. From Lin Yongming's explanation, he had already realized the seriousness of the matter.

"An engine with stronger performance and more advanced technology."

"We don't have to buy this engine. We may not even have to wait for the WS-10."

"It's better not to fly than to fall. I think it's the right thing to do. I'd rather be late and not go in the wrong direction."

Hearing this, Wang Ming was shocked beyond words.

"It makes sense, but it's also wrong. Didn't the 606 Institute look at it? There's not enough data to see the problem."

He subconsciously wanted to ask clearly, but soon realized that this might not be the question he should ask.

Lin Yongming on the other end of the phone sighed heavily.

"Leader, I understand what you mean."

If this is the case, then the J-10 will definitely not be able to use this engine.

"Then do you know what the flaw is in this design?"

However, at the same time, another question arose in his mind:

Who discovered this problem?

It's not the 606 institute either, because just earlier today, I discussed the issue with them about this engine.

"Such a design, whether it is flow, speed, or pressure, cannot form reliable lubrication and cooling effects. This is the fatal flaw of this engine!"

On the other end of the phone, Lin Yongming interrupted Wang Ming mercilessly.

Wang Ming's tone was firm. His confidence came not only from the so-called "Russian experience", but also from the professional judgment of experts from the 606 Institute.

"It looks like it's going to be a bit troublesome now. If the AL-31FN is really stopped, our plane will still be flying!"

"Double intermediate bearing, four-bearing low-pressure rotor design."

At this time, most of the people in the conference room also heard the content of the phone call. Everyone looked at each other, not knowing what to do for a while.

Lubrication reliability. This is a direction that he, and even the researchers at the 606 Institute, have not considered.

"That's right!"

"We have been promoting this introduction project for two full years. Not only has everyone put in their efforts, but the progress of the J-10 project is also in line with the introduction work."

Half an hour later, in a completely closed office.

"Do you know why this engine performs better on the SU-27 than on the J-10? Why is its failure rate on the Su-27 so much lower?"

Lin Yongming on the other side replied decisively.

"That's right! This is the key to the problem! All the main shafts of this engine need to be fixed and supported by roller bearings. The rotation of the roller rods requires a large amount of lubricating oil to reduce friction so that they will not be sintered or peeled off.

Extrusion deformation, even rupture and wear.”

So, he could only calm down, change the topic and said:

"So now you know why I stopped the introduction."

The reason is simple, load!

"Maybe you don't want to work on a new project? Maybe you are forced to do it?"

"This is impossible! AL-31FN is a time-tested engine, and its performance on the SU-27 has always been very good. Although there are constant minor problems, there is no problem with the overall performance and design concept."

"After all, this engine has been certified by 606. Judging from our current conditions, it is a qualified product."

"What if they weren't the ones who saw the problem?"

"However, due to the special design of the AL-31FN, the bearings between the rotors, regardless of the inner and outer rings, are connected to high-speed rotating parts. There is no way to install a fixed lubricating oil nozzle, so we have to settle for the next best thing and first transfer the lubricating oil.

It is injected into the interior of the low-pressure turbine shaft, and then the high-speed rotation of the turbine shaft throws the oil from the left and right sides toward the bearings."

"If the introduction plan is temporarily canceled now, the entire J-10 project will be affected."

"Forced? Are you saying that the AL-31FN has major flaws?"
To be continued...