Chapter 325: To understand the mind and see the nature, you can see God!

Author: Mei Zixu

"What do you mean is that you want to do another radius-free spiral operation displayed at Qitai Airport?" After listening to Xu Cang's introduction to the situation, Bi Lin soon realized Xu Cang's thoughts.

In fact, as a witness to the shocking operation at Qitai Airport, Bi Lin could understand Xu Cang's thoughts better than anyone else.

"Yes, but not exactly." Xu Cang pondered for a moment and organized the following language a little: "The airflow from the air outlet in the valley near Qitai Airport is relatively stable, and it is easy to control the aircraft in a relatively critical state. However,

This time, the airflow in the Alps is not only stronger than the strong winds at the mountain pass at Chitai Airport, but also quite unstable, and it is impossible to maintain a stall angle of attack."

"What do you mean?" Bi Lin was a little confused: "Or, do you want to complete the approach under the super-large headwind with a large meter speed and a low ground speed?"

"That's about that." Xu Cang paused: "Old Bi, do you think it's feasible?"

Bi Lin was obviously silent for a moment, and it seemed that he was seriously thinking about the feasibility of this plan: "Can you ensure that the airflow will be completely parallel to the direction of the runway? According to your opinion, if you want to achieve ultra-low ground speed, you must get close to the wind when facing the wind.

One hundred knots. As long as the wind direction is slightly angled to the direction of the runway, the crosswind component generated will be unparalleled. The aircraft can withstand greater winds, but it is difficult to withstand greater crosswinds."

Xu Cang seemed to have thought carefully: "The core of the local cyclone is a wedge-shaped tornado, with a length of more than one kilometer, and its EF level can reach level 4. If shown according to the cloud map, there will be a short moment in the center of the tornado soon.

Through the sky above the manor airport, this will cause the air flow on the manor to be completely parallel to the direction of the runway. After terrain friction and blockage, the wind speed will decrease to about 200 km/h, which I think is a relatively appropriate value.”

Unlike the commonly used Pofuku level, tornadoes usually use the enhanced Fujita level, with a level of only 0-5. So far, no EF6-level tornado has been found.

According to conventional experience, the EF level of a tornado is related to the form of a tornado. For example, the EF level of chimney-type tornado and rope-type tornado is slightly lower, and generally does not exceed level 4.

However, the EF level of the wedge tornado is usually higher, and can basically reach EF4-5.

Of course, there is also a twin tornado, which is not necessarily of the level, intensity, and range of influence.

According to the satellite cloud map, the width of the tornado in the core of the Alps cyclone has not reached its maximum value, and its EF intensity should be between level 4 and level 5, with the predicted wind speed of 300 kilometers per hour.

However, there are many gullies in the mountainous areas, and the airflow will be much smaller when blocked by the mountains. In the end, the airflow in this site should only be frozen at 200 kilometers per hour. Such a wind speed is more in line with Xu Cang's requirements.

If the tornado is too strong and reaches EF5 or above, the wind speed usually exceeds 350 kilometers per hour. Even if this wind speed passes through the terrain, it will be too high for approaching aircraft. These extremes are some extremes

Under the circumstances, it is obviously not feasible that the aircraft cannot form a positive ground speed under such a strong wind under such a strong landing configuration.

But if the wind speed is too small, it will not be able to significantly reduce the plane's ground speed.

The final wind speed of the 200 kilometers per hour in this game was exactly right. If you increase one point, you will lose one point. Perhaps this is the only place where you look at Xu Cang a little bit.

"The EF4 level is a little larger, but the mountainous terrain is rugged and the wind speed in this field should be more appropriate under the barrier of the terrain." Bi Lin still agreed with the calculation.

Not to mention Xu Cang in other fields, but when flying, it is almost completely unscrupulous. He will take all the factors into consideration. What Bi Lin has to do is to check for omissions and fill in the gaps.

But the obvious fact is that Xu Cang's plan seems to have no need to change.

"What would you expect to reduce the ground speed to extremely low with a strong headwind?"

Xu Cang almost thoughtlessly: "Within fifty knots, this will be a relatively safe value. I will choose the landing configuration based on the actual wind speed. The airflow in this field is too messy, and if all the flaps are released, it may not be maintained.

Live in the airplane. And, I can’t guarantee that the terrain will cut the wind speed to 200 km/h, and I will use flaps with restrictive use if necessary.”

"Yes, releasing too much flaps will reduce the aircraft's ability to resist gusts. Using flaps in part is indeed a good choice." Bi Lin thought for a moment: "In addition, my advice is not to increase too early.

The stability of the aircraft is used to put the landing gear early.”

"Huh? Why?" Xu Cang was stunned. He really had the idea of ​​putting the landing gear early in his plan.

Since the landing gear will stabilize the yaw like a vertical tail wing after it is lowered, if there is too much airflow, Xu Cang plans to lower the landing gear a little in advance.

However, unexpectedly, Bi Lin directly denied Xu Cang's idea.

"Xu Cang, you still haven't flew enough. Maybe you have never encountered such extreme ice and snow weather, so your understanding is insufficient." Bi Lin paused: "I used to fly in the Northeast, and then

The heavy snowy weather at minus 34 degrees Celsius is of course not as good as the current situation in the Alps. However, because the height was too high that day, I couldn't get down, so I put the landing gear early to increase the descent rate."

Xu Cang frowned and released the landing gear in advance to increase the descent rate was a very normal operation. But as Bi Lin meant, something big happened later.

"I looked three or four minutes in advance, but these three or four minutes almost made me give my life." Even after so many years, Bi Lin always felt scared when he thinks of the past: "There is nothing unusual in front of me, but

As soon as the plane was grounded, the direction of the sliding run was immediately out of control. No matter how I controlled it, the plane still rushed out of the runway. At that time, due to the impact, the engine caught fire. Fortunately, I ran fast and had just run out for more than ten or twenty meters.

, the plane exploded."

Bi Lin stabilized his mood a little: "Later, after investigation, it was snow water that accumulated on the landing gear and freezed the shaft of the landing gear directly. My right landing gear wheel did not turn after it was grounded, and it was always in

Locking state. Later, I looked at the wheels of the right landing gear. The tires that came into contact with the ground had all been worn out and the wheel hubs were exposed. Xu Cang, this is the only flight accident in my life."

"Xu Cang, you have to remember that ice accumulation is always a taboo in flight, and you must be careful." In the end, Bi Lin gave Xu Cang a special instructions.

Xu Cang heard it and was silent for a long time. He had never encountered too many rainy and snowy weather, nor had he seen such an exaggerated ice accumulation. After the snow water freezes, the landing gear wheels can be frozen directly.

Xu Cang really never thought about such a thing.

This is experience, the most valuable experience.

"Old Bi, I understand." Xu Cang said from the bottom of his heart: "Thank you."

The situation in the Alps is definitely worse than that in the Northeast when Bi Lin was in the past. Bi Lin put down the landing gear a little early, and it almost became glorious. If Xu Cang still did it according to the plan, he would do it.

Even if you die, you will not have a place to bury it.

You know, Xu Cang planned to lower the landing gear after entering the cyclone zone depending on the situation. This was not three or four minutes in advance, but probably it was nearly ten minutes in advance. According to the situation in the Alps, it is probably all landing gear wheels.

They are all going to freeze to death.

The thickness of snow at the Manor Airport is already severely exceeding the standard. If it is grounding and slipping, wouldn’t it be a complete dead end?

With this suggestion alone, Xu Cang felt that the call to Mr. Bi was worth it.

No, it should not be said to be worth it, it should be said to be life-saving.

"Also, I suggest only half of the gear flaps." Bi Lin said: "The existence of flaps can originally play a role in stabilizing the aircraft. However, it is not necessary to release all flaps, it is not about resisting gusts.

The situation, or not, is. If you say that a normal wind storm parallel to the runway can be formed at the airport at a certain point in time, then the flight mechanism and approach speed are not very important, and the wind storm is enough

Limit the ground speed to a level that satisfies you.”

"Then the flap should be used, it should not focus on the gear selection of approach speed, but should be used to deal with turbulence and some emergencies. You and I know that like the landing gear, the existence of flaps will be in

It is understandable to increase the stability of the aircraft to a certain extent, which is intended to increase the stability of the aircraft in a turbulent environment. However, no matter how stable the aircraft is, once the airflow suddenly changes, the aircraft will still undergo huge changes in state

.At this time, the stability of the aircraft is not a favorable factor, because it will inhibit the pilot's stress response operation in a short period of time."

"So, the release of half of the flap is a good choice, not a choice to position the flap gear to correct the ground speed." Bi Lin coughed gently: "Xu Cang, your technology is perfect

Flawless, any technical problem is not a problem for you. What you lack is only some experience accumulated through time. For ordinary people, in this kind of strong winds and turbulent weather, the more stable the aircraft is, the better.

.However, for you, compared to the stability of the aircraft, you should trust your own technical level more. You should use the ability to take the lead to correct the impact of turbulence on the aircraft. We have always corrected that the aircraft is always

In the slightest, if the plane is too stable, it will be a bad thing."

In fact, this is already a bit of a fighter thinking.

The stability and maneuverability of an aircraft are always a pair of front and back sides. Bi Lin’s meaning is very simple. Ordinary people do not have such strong control capabilities, so they naturally tend to be stable in order to correct the aircraft less.

But for those who have achieved perfection in technology, they cannot oversuppress the maneuverability of the aircraft, because this means that it is naturally undesirable to make things worse than the strengths.

"However, Xu Cang. You have never been flying in such a harsh and violent weather conditions. If you are not careful, you will only be on the way to death. To be honest, I don't recommend you to go." Bi Lin was extremely sincere

: "It is extremely rare to survive in this environment, whether it is civil aviation or all flight history. You must understand that the problem you are facing is not a landing distance, and you may not even be able to get close to the center of the cyclone."

Xu Cang just smiled and said, "Old Bi, you don't know some things yet. There is one thing you said right, any technical problems are not a problem for me now."

"Is that true?" Bi Lin didn't say anything, but just changed his mind suddenly: "Xu Cang, I hope you don't blame him for the previous matter of Old Man Si."

When talking about this, Xu Cang's face did not fluctuate much: "That was the old man's wish, so I naturally wouldn't blame him."

"Xu Cang, Gong Yue from Xianchi Branch is not bad by nature. He is from the Northwest. He wants independence to contribute his own efforts to the development of the Northwest." Bi Lin said: "Previously, Muhua's headquarters were mostly from the Northwest.

It is restricting the Xianchi branch. On the one hand, it draws a lot of profits from it, and on the other hand, it does not allow it to develop freely, which has caused the deeper grudges in Gong Yue's heart."

Xu Cang raised his eyebrows, which was the first time he heard analyzing Gong Yue from the bottom of his heart. If Bi Lin was right, then this suggestion on dealing with the Xianchi branch would have a decisive effect.

"I understand, I already have some directions." Xu Cang said: "Thank you Mr. Bi for your reminder."

"It's all right." Bi Lin paused: "If you have made up your mind, then I will naturally not stop you. I wish you good luck."

Xu Cang nodded: "Old Bi, then I'm dead."

As the phone hung up, the dark room fell into darkness again. Xu Cang sat quietly, not talking or moving, as if he was integrated with the darkness.

In the office of the director of the Hanjing Test Flight Institute, thousands of miles away, the sun was gentle outside, and there was no bleak feeling like Munich at all.

However, compared to the outside atmosphere, the atmosphere in the office is extremely solemn.

A video was playing on the TV in a corner of the office. If Xu Cang was here, he would definitely find that this video was a video of him landing at Munich Airport on British Airways Flight 531.

At that time, a European Civil Aviation Conference happened to be held near the airport, and a large number of media personnel carried professional camera equipment, which was to take a clear picture of Xu Cang landing.

However, this video has not been released yet, but has fallen into Bi Lin's hands, which shows how powerful Bi Lin is.

The shooting effect of professional equipment is very good. Even before the plane landed, the camera was pulled and the details of the plane landed were taken into it. In the picture, you can clearly see that the right large wing of the British Airways Boeing 777 was broken.

But the plane landed on the runway in an incredible state.

"How did he do it?" Beside Bi Lin, Chen Gang, the chief of the Flight Test Institute, was puzzled: "Or, how did he stabilize the plane before approaching. If the big wing breaks, the plane should be in

It's just that it's out of control in an instant."

"Maybe it is to exchange the functions of the elevator and the rudder to operate the aircraft in a more remote way." Bi Lin sighed: "I said before that he has not reached his peak, but I really don't.
To be continued...