Kyushu Academy of Sciences.

Liu Jinghong and others were anxious to follow up on the aircraft project.

When they actually put the aircraft project on the agenda, they realized how difficult it really was.

Yes, when the aircraft appears in that shape, it generates the forward momentum, and it does generate lift.

But that's just a rough principle, and there's too much more to be learned about aerodynamics, fluid mechanics, structural mechanics, and materials engineering.

A discipline has fallen into a bottleneck, causing all academics to enter a bottleneck. Everyone is looking for a breakthrough, and the opportunity to break through is to cross this hurdle.

It may be difficult for outsiders to understand why the development of a flying machine will lead to a bottleneck in all disciplines.

In fact, if we look at the situation in a broad sense, we can see this problem.

A flying machine in the true sense of the word is not as simple as an airship. Because the knowledge involved is too extensive, it is no exaggeration to say that if the aircraft can be successfully developed this time, the test will be successful.

Then the science of the whole world will collectively go up a level.

Aerodynamics, fluid mechanics will be more demonstrated, as well as more theories of practical data.

Materials science will go up a notch. Aerospace materials have been developed that will push the industrial level of New Kyushu up a notch.

Dynamics will go up one step.

Because if the radial reciprocating engine is successful, then the power of this world will leap from the age of steam to the age of fuel in a short period of time.

The upgrade of dynamics will allow all the power-related knowledge of New Kyushu to add more new directions.

After that, people's understanding of the world will increase.

It can be said that this seemingly simple aircraft project actually covers an extremely wide range of aircraft, and Li Zhen can't afford not to pay attention to it.

During this time, Li Zhen moved into the aviation institute and discussed the fuselage structure with Liu Jinghong and others.

Because of the problems of the radial reciprocating engine, there are only permutations and combinations, and it only takes time to try and make mistakes to draw conclusions.

The School of Materials also requires a lot of trial and error, and among the existing alloys, new alloys are fused. There is no formula, and the ratio of this aviation material cannot even be found by Zhang Zhi.

After all, in her time, these were high-end sciences. Basically, it's all state classified data.

Li Zhen doesn't want to be able to reach the level of those countries, he only pursues one that can fly into the sky, can be used, and is safe. But just such a minimum requirement also requires a lot of trial and error to support.

Then Li Zhen can only help, and the only one who can do it is the Aviation Institute.

At least in aerodynamics, it's not just trial and error.

Li Zhen drew a picture on the blackboard, and the sketch was very much like the appearance of an early fighter jet in ancient times. But the difference is that the wings of this sketch are double-layered.

In addition, it can also be found that this aircraft, like the airship, follows the inertial thinking of the airship. The power plant was set in the rear.

If the power of the early fighter came from the nose of the aircraft, then the engine system of the middle period was on the wings.

Only for the top fighters of the later period, the power system was in the tail.

Conventional aircraft are the nose of the fuselage that generates a pull force. The aircraft designed by Li Zhenhe Aviation Institute is the butt to produce thrust.

Li Zhen tapped the blackboard with chalk: "The first-generation aircraft that Xu Xiufeng mainly conceived was named 'biplane aircraft'. Let's focus on this wing. What do you think? ”

Liu Jinghong stood up and frowned, "Master Li." According to the theory of wind resistance, the wind resistance generated by the double-layer wing is actually greater. And the fuselage is heavier. It's going to be extremely slow. Moreover, this wing is in the middle of the fuselage, and if the counterweight is not up to standard, it will only cause one consequence. ”

Li Zhen asked, "What consequences?" ”

Liu Jinghong said: "The plane itself is too heavy, and the wind resistance has also increased. If the power is not up to standard, or if the engine stalls in the air, there will be a big problem. Either the plane will fall vertically, or it will fall over its heels. ”

Lin Xiufeng frowned and said, "What Dean Liu said is not right. All this is based on the condition that the engine is turned off in the air. So I want to ask you, if the biplane can't do it, will the monoplane air engine go out and won't fall down? ”

Liu Jinghong said: "The single-layer wing aircraft is lighter and more flexible. So with the impetus of the engine, the speed will be faster. Under the same conditions, if the engine turns off in the air, then the aircraft with single-layer wings glides down. ”

Lin Xiufeng said: "I know gliding. But double wings can also do gliding; And more stable. Now that the material limits our imagination, then on the current material, the double wings are obviously more stable. The single-layer wings you mentioned are not stable enough, and in the air, the wings have to bear the weight of the aircraft. If the wings are not strong enough, they may even be broken in high winds. The double wings, on the other hand, solve this problem. Safer and more stable. ”

"What you're saying is even more wrong. Quality is relative. We can test the maximum weight of the single-layer wing material, within which we can set the weight of the aircraft, as well as the pilot's weight, and the load weight. These can be solved. But your double-winged plane, stability is stability, but it can't glide and land at all. ”

“……”

The two quarreled.

Li Zhen frowned and was also thinking deeply, looking at the flying machine on the blackboard, trying to grasp something hard, but he couldn't grasp that little light in his mind.

Single-ply wings have the benefit of single-ply wings.

Double wings have the benefit of double wings.

Zhang Zhi said that during World War I in ancient times, there was no shortage of such double-decker winged aircraft. It's called Bumblebee.

But the further back it goes, the kind of double-winged ones are eliminated.

But why it was eliminated, Zhang Zhi couldn't say clearly. Zhang Zhi's main focus is not aeronautics, and the data and principles in aeronautics are not something you can find on the Internet.

But Li Zhen knows that there must be a reason to be eliminated. Everything in the world is survival of the fittest. Now that the double-winged Hornet has been eliminated and single-winged aircraft have become mainstream, there must be some truth to it.

Perhaps, as Liu Jinghong said. The double-layered wings are stable and able to share the weight of the reduced fuselage. But it's too slow and cumbersome.

Single-layer wings are obviously more efficient at breaking the air.

Double-layered wings, on the other hand, will obviously be twice as long as single-layer wings. The speed will also be reduced.

Don't underestimate the seemingly small discrepancies.

You know, that's aeronautics. You know, the imagination of the whole world is limited by the current existing dynamics.

In the air, if the power is insufficient, the consequences are extremely serious.