Chapter 1206 Aerodynamic Vector Nozzle, a Ray of Hope?

Although he had expected the outcome, Sun Cong couldn't help but feel a little regretful when it came to this moment.

The first thing that the 601 Institute was optimistic about was indeed a three-wing plan, which focused on achieving stronger maneuverability with a relatively weak power level.

However, due to well-known reasons, about a few years ago, there were some small changes in the premise of "weaker power level", so they also took advantage of the situation and shifted their focus to conventional layout and semi-tailless layout.

This time we also brought two sets of plans at the same time, and we are ready to decide which one to put out based on the on-site conditions.

Therefore, when Chang Haonan took out the indicators of the turbofan 10G, they already had the idea of ​​​​competing with a semi-tailless layout.

Coupled with the targeted speeches from the 611 Institute later, the delegation finally reached a consensus.

After all, they also considered that Academician Chang could come up with a quasi-fourth-generation turbofan 10 in less than five years, so it seems reasonable to take less than five years to come up with thrust vectoring technology now.

But success also comes with failure.

The last glimmer of hope for this plan was extinguished with Chang Haonan's statement.

Correspondingly, Yang Wei, who was sitting opposite him, breathed a long sigh of relief and couldn't help showing a relaxed expression.

In fact, until not long ago, even within the 611 Research Institute, there were still some different voices on whether to continue the J-10's airfoil configuration in the design of the fourth-generation fighter jet.

Especially considering the rapid progress of the domestic aviation industry, it seems that it is not impossible to come up with a model that can compete with the F119 in about 10 years.

In this case, directly replicating an F22 is obviously the least risky option.

As for the intermediate transition period, the turbofan 10B, which has already passed the test on the J-10, can be used as a replacement.

However, on the one hand, 601 has insufficient accumulation in conventional layout, and it is difficult for a satisfactory plan to stand out within the group.

On the other hand, Yang Wei himself does not want to simply follow the Americans.

What he just said as an opening statement was actually not only for others to listen to, but also for himself.

Fortunately, the final result is still in line with expectations...

…

After all, the Aviation Industry Group is a whole. Although the subordinate units may have differences in technical routes, in general, once the direction is determined, they can still work together.

For example, the 611 Institute had no experience in designing twin-engine heavy-duty aircraft in the past, so although it gained the initiative in design and layout, it still needed the help of other brother units in terms of structure.

Therefore, the rest of the entire meeting basically consisted of communicating with representatives from the Air Force Equipment Research Institute such as Lu Guang, and continuing to deepen some details based on the canard + delta wing solution.

In fact, although Chang Haonan has been an executive in the Aviation Power Group for several years, he still started his career in aircraft design.

So even in the second half of the meeting, there were still people asking him questions from time to time.

But in the face of these questions, Chang Haonan basically only gave the most basic answers, and did not expand as much as he did just now——

It's not to avoid suspicion in business, but he is still thinking about the semi-tailless plan proposed by 601.

After all, from the perspective of equipment habits, for the sake of risk sharing and business balance, the air forces of major countries generally do not equip only a single type of main fighter aircraft.

Technically speaking, the canard + delta wing layout is not particularly suitable for carrier-based aircraft due to its flight characteristics during takeoff and landing.

This can be verified from the technical data of Rafale M on hand.

More importantly, the semi-tailless layout just fits an important new technology that Chang Haonan is planning to develop in the next stage...

Therefore, during the lunch break of the meeting, Chang Haonan took the initiative to find Sun Cong, who was still a little depressed.

Although the two have not worked together directly, Chang Haonan has worked in the 601 Institute for a long time, and he and the latter also received the "Operation Bat Hunting" commemorative medal, so they can be regarded as old acquaintances.

Due to limited time, after a brief greeting, Chang Haonan got to the point directly:

"Mr. Sun, in the meeting just now, I was just discussing the matter. In fact, I am quite interested in the semi-tailless layout of our 601 Institute..."

Of course Sun Cong knew that the other party was not targeting him.

But humans, it’s inevitable to have emotions at times like this.

Of course, since Chang Haonan is now an academician, he cannot really show any dissatisfaction.

But I still don’t want to mention this sad thing.

So I immediately prepared to change the topic:

"I understand, Academician Chang... it's all in the past, there's no need to mention it again..."

As a result, he was interrupted by Chang Haonan just halfway through speaking:

"I'm not being polite, I'm really interested in this plan."

He said and pointed to the PPT that was still open on the computer screen next to him.

Sun Cong was silent for a moment, then sighed heavily, still unable to hold back, and spoke:

"Academician Chang, if you really take the lead in vector propulsion technology, won't you really be able to overcome the lifespan problem?"

Obviously, he still felt unwilling in his heart.

Chang Haonan did not answer this question directly, but showed a smile and whispered:

"Actually, I came to you this time just to discuss this matter in detail..."

Hearing this, Sun Cong's face flashed with surprise for a moment.

Then he showed hope again.

"At present, we are testing on the ground, including several vector nozzles that have been put into use by the United States and Russia. Whether it is a guide plate type, a convergent adjustment plate type, or a dual pitch type, or even a swing type used in rocket engines, they are all mechanical thrust vector nozzles."

"Although the principle of adjusting the thrust direction through a mechanical structure is simple, the control mechanism is complex, the cooling and sealing are difficult, and the extra dead weight is heavy... Moreover, adding hundreds of tiny moving parts out of thin air will inevitably affect the reliability and lifespan no matter how advanced the technology is. This is determined by engineering principles..."

Chang Haonan paused for a moment when he said this.

Sun Cong also nodded to show that he understood.

"So I have been thinking about developing an aerodynamic vector nozzle with a fixed geometry, so that the performance loss caused by the complex mechanical structure can be avoided."

This time, Sun Cong was a little confused...

"A vector nozzle with a fixed geometry?"

He frowned, and even doubted for a moment whether he had heard it wrong.

The core function of the vector nozzle is to change the thrust direction.

But it has to be fixed in geometry...

It feels like "zooming in and then shrinking a little" or "colorful black".

Chang Haonan also knew that his statement was a bit strange, so he quickly explained:

"You should know that the ejector nozzle used on the old turbofan 10 is to adjust the throat area of ​​the nozzle by injecting secondary flow at the throat of the nozzle, right?"

The old turbofan 10 he mentioned refers to the version that was abandoned before he took over.

Sun Cong nodded subconsciously at first, and then showed an expression of enlightenment: "So that's it":

"You mean, injecting secondary flow in an asymmetric way inside the nozzle, so as to control the direction of thrust generation through the secondary flow effect?"

"Yes, that's why it's called aerodynamic vector nozzle"

Chang Haonan looked at the layout rendering of the semi-tailless layout again:

"But this technical route requires a very precise engine electronic control system and a much larger engine air intake than the conventional one, so a newly designed aviation platform is needed to fully exert the performance advantages..."

"I don't know... What do you think, Mr. Sun?"