Rebirth of Military Workers

Chapter 253

“Skilled workers are also part of the production line, right? Is there anything wrong with what I said?” Zheng Yucheng asked awkwardly when everyone around him looked at him with a smile.

“Yes, this idea is very good, very good!” Xie Kai sighed and smiled, “Old Zheng, don’t you think you are too insidious? If the people at McDonnell know it, do you think they will be chased all over the world? kill you?”

“How come I am insidious? You came up with this idea at the beginning.” Zheng Yucheng said in surprise.

Xie Kai clearly proposed how to evacuate the 5703 factory.

Of course, he also mentioned that it is definitely not as perfect as Xie Kai’s plan.

“Yes, do we still have to do business?” Du Shengfeng was secretly surprised, no wonder Zheng Yucheng took this kid wherever he went, not a fuel-efficient lamp.

Fortunately, I didn’t offend this kid, otherwise I don’t know when I will be overcast in the future.

“What’s the situation with Qin Fei’s Yunshi now?” Zheng Yucheng asked Ma Fengshan as he walked.

Two hundred hours of safe flight time has passed. Up to now, the first flight test prototype has flown for 237 hours, and the location of the welds of the main frame beam structure has begun to show subtle cracks.

Now how to solve this prototype is to continue the test flight after rebuilding it to obtain more flight data, or to stop the test flight altogether and wait until the other aircraft is assembled to continue the test flight. You must come up with an idea.

“Our opinion is to re-weld, and then continue to test flight!” Ma Fengshan said gravely, “Many problems with the new one cannot be exposed.”

“We have not undergone finite element analysis. How much is the difference between the calculated data of the simulated structural strength and the actual data?” Xie Kai asked.

Yun Shi already knew these issues when they took over.

So no one is going to investigate how the problem arises, or how the problem is caused.

They are all aware of the reasons for these problems. The core structural parts produced cannot reach the designed strength due to the lack of large presses.

Hundreds of tons of flying weight continue to fly in the sky, and cracks appear in the key positions of the aircraft to withstand all the gravity. Everyone knows it.

“The actual situation is not much different from the data obtained by the simulation analysis. After the assembly of another aircraft, the safe flight time can be increased to 300 hours, which is not helpful for commercial aircraft.” Ma said. .

“Can you improve so much time?” Xie Kai was curious, “Aren’t they all using the same processing method and assembly method?”

“The problems exposed in the production of parts and components during the flight test of the first prototype were gradually improved from the beginning, and the process of assembly was also improved.” Mr. Ma explained, “but in the main structural parts In the production process, without a large press, large forgings cannot be formed at one time. In the end, small forgings are still spliced…”

It is still a problem caused by the lack of key processes.

“So, as long as the big press can’t get it out, the problems that Yunshi faces can’t be effectively solved?” Zheng Yucheng asked bitterly.

The more I think about it now, the more I feel that it was too ideal.

“Yes, a 45,000-ton large press can solve these problems. The frame beam structure of the main structure part is forged and formed at one time and processed as a whole to solve this problem. Otherwise, the problem of structural strength not reaching the design life can be solved. “Ma Fengshan said.

Several people have already walked outside Qin Fei’s Yunba assembly workshop.

The huge Yunshi just parked alone on the huge runway outside the assembly workshop.

From the outside, you can’t see what’s inside the plane.

Under the leadership of Ma Fengshan, several people boarded the plane. Inside the plane, especially in the middle of the fuselage, some of the interiors have been disassembled, and the structure of the fuselage frame can be clearly seen.

Some designers of the original Yun-10 team are carrying out various inspections inside the cabin, and they are constantly recording them in their notebooks.

“There are no cracks.” No matter how Zheng Yucheng looked, he couldn’t see the cracks in the weld on the plane’s beam.(Read more @ wuxiax.com)

“It can’t be seen by the naked eye, but it can be clearly seen with a magnifying glass.” Ma Fengshan took a magnifying glass from the staff nearby and handed it to Zheng Yucheng.

Zheng Yucheng put the magnifying glass close to the welding seam, and then moved it up by himself, only to find a crack in it that was as thin as a hairline.

“There are not too many places above. The more the cabin bears the weight, the cracks become denser. These cracks were discovered during the inspection, so the flight is stopped now…” Ma Fengshan took a few people from the ladder to the belly of the plane. Inside the cargo hold, he pointed to the exposed position of the bottom frame beam and said.

The bottom part bears the weight of the entire aircraft. Since it is not formed at one time, it is connected by welding after forging in sections to form a long beam to bear the weight of the entire aircraft.

In some places, even without a magnifying glass, you can see dense cracks under the light provided by the flashlight.

The surface of the aluminum alloy is smooth, and a little abnormality can be seen clearly.

“If this plane wants to continue to fly, the beam must be replaced.” Ma Fengshan looked at Zheng Yucheng and said quietly.

“Didn’t other frame beam structures also have cracks?” Zheng Yucheng was puzzled.

“The same is true, while testing and replacing, only in this way can we get more comprehensive data.” Ma Fengshan said.

Xie Kai has been observing the internal structure of various main parts. The core structure has problems, and the beam that bears the weight of the entire aircraft has problems. This aircraft is no longer necessary to continue flying.

Must be scrapped.

Otherwise, on the next flight, it may disintegrate.

“Stop it!” Xie Kai sighed.

No one is willing to accept such a result, but they have to accept it.

“Replacement of the girder and frame beam structure can be re-flyed without affecting safety. Compared with remanufacturing, it will save at least three-quarters of the cost.” Ma Fengshan said hurriedly.

What they consider is cost.

404 raises its own funds so that the Yunshi aircraft can continue, and they can’t help but consider saving costs.

“Your opinion is scrap?” Zheng Yucheng wants to remind Xie Kai that the cost of an airplane is tens of millions.

Even if the main structure cannot be used, some other things can still be used.

“Mr. Ma, I know that you are considering cost saving. As you said, just replacing the girders, etc., will cost less than ten million yuan. However, if the new girders and the frame beams that are mainly subjected to stress cannot solve the strength structure The problem is that the original processing technology is still used, and in the end it will not be more than 300 hours of flight… It is just the cost of replacing these core structural parts, even if it is calculated at 6 million, it will cost 20,000 per hour!” Xie Kai told Ma Fengshan Calculating the cost.

These costs do not include the cost of man-hours, the cost of fuel required during the flight test, etc.

“Don’t continue flying, there are still some hidden faults that will not be exposed.” Mr. Ma also knows the facts Xie Kai said.

Several people came out of the plane and stood watching the plane that was quietly parked on the runway. All of them had complicated thoughts.

The exterior is glamorous, and no one knows the internal situation.

If you remove the outer skin, you may also find that there will be various problems with the welding positions of the main frame of the fuselage.

There is no large forging press!

The key structure cannot withstand the huge impact force during take-off and landing.

“Is there a problem with the landing gear?” Xie Kai asked.

“It hasn’t been checked yet. According to the results of finite element analysis, at least another 300 sorties can be flown. This is forged by a 30,000-ton press. Although the structural strength does not match the design, it can barely be guaranteed.”

“Is this the best news we have heard about Yunshi?” Zheng Yucheng asked jokingly. “Many airplane accidents occur because of the landing gear.”

But no one can laugh.

The state has invested more than 500 million yuan in funds, and so far, such a result has appeared.

Continue to fly, no one can guarantee that it will not disintegrate in the next flight batch.

Metal fatigue, when it has not reached the original service life, unless there are external forces, it will not cause safety hazards.

Once the limit is reached, cracks begin to appear, and if you continue to use it, this failure will quickly magnify.

The main beam broke and the entire aircraft disintegrated.

“We can’t risk the future of the domestically-made large aircraft. Not to mention that there are so many cracks, even if there is only one crack, and it should be scrapped, we cannot take a fluke. In this regard, the tuition fees we should pay cannot be saved.” Zheng Yucheng Said to Ma Fengshan.

The General Administration of Civil Aviation has now abandoned the large aircraft, and the country no longer invests, but they cannot give up any hope for the entire domestically produced large aircraft for this reason.

In order to save tens of millions of expenses, it is not possible to continue the test flight of the malfunctioning aircraft.

“This aircraft can be used as an experimental platform, whether it is an operating system or other electronic systems, it can be verified on it. New design modifications will be the focus of the next step. As long as there is no problem with the design, we can Before this, we will produce some other non-critical parts. As soon as the big press comes out, we will first assemble it, then we can directly assemble it, and then we can continue the test flight!” Zheng Yucheng comforted Ma Fengshan.

In General Ma’s mind, Xie Kai understands that he doesn’t want this 110-ton large aircraft that can fly for the first time in China to never fly again.

“As long as it doesn’t disintegrate, on the ground, the meaning of this plane will not be worse than flying in the sky.” Xie Kai said to Ma Fengshan, whose eyes were slightly red. “Get ready to produce a newly designed airplane!”

“Start preparing now? The big press hasn’t started yet.” Du Shengfeng asked.

“Prepare, don’t you understand?” Zheng Yucheng’s eyes widened.

Ma Fengshan knew that both of them were comforting him and also showing the determination of 404 in the big airplane business, so he felt a lot more comfortable.