"It was probably a coincidence."

It was already more than five o'clock in the afternoon, and after thoroughly analyzing the data of the fighters, a person said: "This is an unexpected situation, there is no warning, even if it is our fighter equipment troops, there may be an accident, there are no other problems, tomorrow, we will continue to test flights." ”

"Lao Liu's analysis is reasonable, we carefully studied the data and found no other problems, it may be an accidental situation, let's stop here today, let's continue tomorrow."

Everyone has no clue, no one can find the problem, this is not like the previous fuselage tremor or something, there are rules to follow, there are obvious conditions, and the test flight cannot continue.

This situation happened by chance, and the next time you do the same action, you may be fine, in this case, there is no way to talk about how to solve the problem, you can only give up the problem and continue the next scientific research project.

After all, this fighter has a large number of test flight missions in the future, and the platoon is full every day.

"Crunch." At this moment, the door outside was pushed open, Qin Feng and Wang Yang walked in, Qin Feng looked at the people present and said, "This is a design flaw, it is definitely not an accident." ”

As soon as Qin Feng said this, everyone present was stunned, and soon, Lao Liu frowned: "Design flaws? You haven't designed an airplane, how do you know it's a flaw? That's right, last time you analyzed that there was a problem with our hydraulic oil circuit, which was also based on the tail of the MiG-23, and now there is no comparison. ”

Qin Feng's face was very serious: "Our J-8 fighter, since the beginning of the test flight, has there been fewer accidents in the air parking?" Not to mention the previous ones, just last year, there were four cases during test flights! Guys, what does it mean that in 500 hours, there have been four stops in the air? Almost every 100 hours there is one, if we consider it an accident, we ignore it, equip the troops, and our troops face an accident in the air every 100 hours they fly! And even more, because the intensity of our Air Force is greater! ”

Now, Qin Feng has begun to slowly have a status in the test flight team, and as he solves several problems, everyone knows that he is capable and can be regarded as a technical test pilot, which is incomparable to others, and his sense of responsibility is very strong, which is incomparable to others.

Hearing Qin Feng say that it was a technical problem, and he said very clearly that it would be absolutely impossible to ignore the problem of parking in the air like this, and if such a fighter plane was delivered to the troops, the troops must not crash the plane every once in a while?

"In particular, after our planes are parked in the air, it is more difficult to restart, and our pilots are not at the level of test pilots, and they are more dangerous."

Qin Feng's eyes looked at everyone, and finally looked at Mr. Gu's face: "Mr. Gu, I know that our test flight mission is very tense, but our test flight is to find problems, and we must not leave such a serious problem behind!" ”

The expression on Mr. Gu's face was very solemn: "Yes, we have had many air stops in the test flight, but the situation is different every time, we can't be sure what caused it, Qin Feng, have you found the reason?" If you find it, tell everyone about it. ”

It's not that you don't want to solve it, but no one has found the problem, and since you can't find the problem, how can you solve it?

"I learned a lesson from our J-6 fighter." Qin Feng said: "Our air stop this time is likely to be related to the layout of our nose air intake. ”

It's nose intake again! Hearing Qin Feng's words, Mr. Gu's brows furrowed even tighter: "Tell me specifically?" ”

"We use the nose air intake, this air intake method, it seems to be very efficient, but in fact, it is the most chicken, and it is clearly reflected in our J-8."

Lao Liu's face was ugly, Qin Feng said that the plan for the air intake in the nose was personally handled by Lao Liu, but now Qin Feng said that his plan was not good!

I have long known that Qin Feng has been advocating air intake on both sides, but isn't everyone trying to be safe? The J-9 of the 611 Institute is very bold, and the result?

"Our J-8 fuselage is very long, so after the air enters, it needs to go through a long period of time to reach our engine, in this case, the effect of airflow pre-compression is greatly reduced." Qin Feng began his own analysis.

The air intake, in addition to allowing the fighter engines to inhale air, also has a role, that is, to pre-compress the air flow, if it is a hypersonic fighter, there is no compressor, and the rushing air flow is directly enough for speed.

"In order to achieve flight at various speeds, our fighters have air intake cones to adjust." Qin Feng continued: "When we are at high altitude and high speed, the air intake cone will be stretched forward, so as to avoid the situation of excessive air intake, and on our J-7, this is also the case." ”

"When flying level, there is no problem, but when we do a big overload maneuver, we will immediately face the problem of insufficient air intake, especially our huge air intake cone, which will block the entry of air flow at this time!"

If there is no such air intake cone, it is better to say that now, such a large air intake cone just blocks the entry of the air flow, so that the inhaled air is greatly reduced!

"For example, if we turn to the left, the right side of the air intake cone will be blocked as we turn to the left, and the right side of the air intake will be greatly reduced. Causes a surge in the engine. ”

"If our intake tract has a partition, and the two engines each have their own intake tract, then at most the right engine stalls and surges, and finally stalls, but our intake tract is connected, so that the intake is insufficient, and the entire intake is overall and insufficient, and then after a long fuselage, to the back, it is simply choked by the airflow, so the two engines are turned off at the same time."

While analyzing, Qin Feng picked up a model of the J-8 on the side and compared it to everyone.

"It's just your idea, our J-7 also does this, why doesn't this happen to our J-7?" Lao Liu continued to ask.

In short, it's all your mouth, and you can say whatever you want.

"Because our J-8 fuselage is longer, and we have two engines at the same time, IMHO, the design of our air intake tract and the engine do not match at all." Qin Feng continued.

Qin Feng said, after all, this is the first aircraft developed by himself in China, and there are too many situations that everyone has not considered, such as how to match the air intake and the engine, in fact, they are all bottomless.