Chapter 436: Someone wants to buy our passenger plane?
The elders sitting below are all professionals who have been involved in the obscure field of bearings for more than ten years or more. After listening to Chang Haonan’s introduction to the research plan, although they felt that The reporter set the goal a bit high, but he still agreed with the plan itself.
In addition to the clear and logical theoretical analysis and the officially designated identity of the chief designer of the Taihang engine, a considerable part of the reason is that even if a few people have not used it, they have at least seen it. TORCHMultiphysics is a software developed by him.
If someone else brazenly said here that they wanted to use numerical calculations to establish a dynamic model of a nonlinear flexible asymmetric rotor system with complex structures supporting nonlinearity under large external overload conditions, I am afraid it would only be a loss. to ridicule several times.
But Chang Haonan is different.
Although on the surface, his main achievements so far are concentrated in fluid mechanics, structural mechanics and control theory, if we really summarize his results, the common ground is actually in the field of computational mathematics.
There may still be disagreements in the mathematics community about whether this thing counts as fundamentalist "mathematical research", but engineering people don't pay attention to this, as long as it is easy to use.
Chang Haonan could naturally see that the few people sitting below did not believe his claim of increasing the life of the bearings by ten times.
Actually, the figure of ten times was still a conservative estimate made by him because he was worried about scaring these people, but now it seems that it is not conservative enough.
But it doesn’t matter, the results will speak for themselves.
People in the late 1990s really knew nothing about the power of advanced optimization algorithms.
Of course, to ultimately achieve this goal, it is certainly not enough to simply improve the design of bearings.
In fact, after determining the bearing structure, he still needs newer, or more adaptable materials and processes.
Currently, the bearing steel used in China is mainly ordinary bearing steel GCr15 and a small amount of molybdenum series steel M50. This is no different from developed countries. Naturally, the latter is the main source of expensive aero engines.
However, although M50 steel has a room temperature hardness of up to HRC62 and good hot hardness, and can work continuously and normally at up to 316°C, its fracture toughness is very poor, and its d.n value is difficult to exceed 2.4. ×106mm.r/min, which is reflected in the insufficient anti-flaking ability of the bearing surface, which can easily cause irreversible damage under certain extreme working conditions.
This is also the reason why most aerospace bearings eventually expire.
Is there an improvement idea? It’s easy to say. Any graduate student who is engaged in metal materials can explain it clearly——
Reduce the carbon content, increase the nickel content, and perhaps increase the nitrogen content. , and then perform surface hardening treatment...
But just having an idea is not enough. You also need to determine how much carbon to reduce, how much nickel to add, how to harden, what process to use, and what the coating material is...< br>
This is why the raw material everyone uses is M50, but the aircraft engine bearings made by Pratt & Whitney, Rolls-Royce and General Motors have longer life and better stability.
All these detailed issues can only be determined according to the specific parameters and needs of the bearing parts after the detailed design plan is released.
As for how to determine...
In the past, it could only rely on trial and error, highly dependent on the experience of materials engineers, and of course luck, and the investment required was naturally extremely staggering.
But now, Chang Haonan can give them at least some direction guidance.
The efficiency is naturally different.
"There is a long way to go..."
Chang Haonan muttered to himself as he closed the notebook filled with research plans in front of him and looked at the backs of several other people getting up and leaving the conference room.
......
Chang Haonan, as a person who has lived his life again, naturally sees problems with the Chinese aviation industry in the late 1990s, but for people who live in the present , the changes that have taken place over the past year or so can be described as miraculous.
Hao Jing, Yan Liang.
The fourth prototype of the MA-60 and the second full prototype is parked on the tarmac.
A group of people in suits and ties were gathered around the right engine of the plane.
Different from the usual yellow or metallic colors of other prototype aircraft, this aircraft was painted with a blue and white paint scheme for the first time today.
If you have a sharp eye, you will also notice that a trapezoidal flag symbol with red, blue and white intervals is painted on the vertical tail of the aircraft.
Flag of Thailand.
Obviously, this painting is very targeted. "Mr. Jonjit, this is our latest regional passenger aircraft, MA60-100, which is also the basic model of the entire series. It can accommodate 60 passengers in normal layout."
A staff member from China Aviation Technology translated into Thai what Gao Quan, general manager of Haojing Aircraft Company, said about the aircraft.
“Like several other regional airliners of this level, the MA-60 currently uses the PW127J series turboprop engine produced by Pratt & Whitney. There is no difference in performance and working mode, but in the matching As for the propeller, we use a self-developed 6-blade composite propeller with higher propulsion efficiency and safer performance. Combined with the new wing with a large aspect ratio, we can save an additional 8% in fuel consumption.”
When he heard this, the Thai manager known as Jonjit's eyes lit up.
In fact, his trip was to seek a batch of new light regional jets for Bangkok Airways.
Although Bangkok Airways is named after the capital of Thailand, which sounds very powerful, it is actually just an ultra-small airline that has been established for more than ten years. So far, it only has 8 aircraft that are over the age of 20-year-old Schott 330 passenger aircraft and 14 slightly newer ATR72-200 passenger aircraft.
Originally, according to the plan, they were going to purchase a batch of Airbus A320s to upgrade their fleet, but the decision was made in mid-August 1997. Even a fool can feel that the economic situation in Southeast Asia is not very good. Satisfied, the management decisively carried out a wave of consumption downgrades, turning the four mainline airliners in the original purchase plan into six regional airliners with 50-60 seats.
Logically speaking, there are not many choices for aircraft of this level. Considering that Bombardier’s latest rush 8-400 is still a piece of cake, even the prototype has not yet rolled off the assembly line, and the rush 8 -300 is already an old model from nearly ten years ago, so the only remaining option should be to continue purchasing the new generation ATR72, which is the ATR72-500 aircraft.
However, the importance of advertising is reflected at this time——
The excellent performance of the MA60 at the Paris Air Show gave Bangkok Airways management a moment of hesitation.
China Aviation Industry is basically very transparent in the field of civil aircraft, but AgustaWestland is an Italian company after all, so it is still somewhat convincing.
Moreover, also during the air show, China was advertising overwhelmingly that they had reached mutual recognition of the airworthiness of regional aircraft with the European Union. Later, it was reported that they had reached a similar agreement with the United States. news.
These two things played a decisive role in improving the confidence of foreign users.
More importantly, although from the price point of view, MA60 is only slightly lower than ATR72, considering that China and Thailand are neighboring countries, the after-sales service is definitely cheaper and more convenient than ATR. .
As a result, Bangkok Airways' board of directors finally decided by one vote to give the new model a chance.
For China, this purchasing intention from Thailand is a complete surprise.
Although Chang Haonan has reached mutual recognition agreements with Europe and the United States on the airworthiness of regional aircraft through some showy maneuvers, even he himself actually has the idea of fighting for the future.
Passenger aircraft still need a bit of word-of-mouth accumulation.
At least in the first two or three years, domestic airlines were still the main operators.
Chang Haonan has even thought about integrating several airlines that are relatively suitable for operating short-distance regional aircraft, such as Beijiang Airlines and Qian Airlines, into United Airlines in the airline integration plan that will be submitted soon, even if it is a loss. We will continue to operate MA60.
As a result, domestic users have not yet been found, and the first ones to come to our door are foreign customers.
It’s no wonder that General Manager Gao Quan has turned down many things and still has to personally take charge of the reception.
Six aircraft are just small shrimps for Boeing and Airbus, but for China Aviation Industry, it is a complete milestone.
“Can I go inside the cabin and have a look?”
Jungjit looked up at the fuselage.
The Chinese people specially painted this prototype with their company's livery, which is undoubtedly a sign of sincerity.
“Of course, come this way, the ramp truck will be here soon.”
Gao Quan had obviously been prepared for it. He picked up the walkie-talkie and said a few words, and a ramp truck stopped coming. It drove slowly from a distance.
Due to the limitations of the original structure, the cabin doors on both sides of the MA-60 are set at the tail, making it shorter than the other two regional turboprop airliners, even for passengers with a height of about 1.7 meters. You need to bend down to get in.
It's a minor disadvantage.
However, the environment inside the cabin made Jonjit quickly forget about the little unhappiness he had just experienced.
(End of this chapter)