Genius is just the threshold for me!

Chapter 17 Mach 0.85

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Seeing this, Lin Dong adjusted the joystick to level the model drone, pointed the camera at the sun and the beautiful landscape below, and pressed the shutter button.

"Look, the three rivers converge in the lower left corner, and the model airplane has reached the Hengduan Mountains..." At this moment, Zhang Yue seemed to have discovered something and shouted, pointing to the scene captured by the camera.

"This communication is really stable. The Hengduan Mountains are about 800 kilometers away from here, and the signal is still so stable." Wang Rui looked at the constantly refreshing avionics interface without any lag and a hint of amazement appeared in his eyes.

"A military-grade satellite communication module, this one module costs 22,000 yuan, and Dongshen has specially improved the communication program..."

At this point, Cai Wei was no longer worried about the model airplane going out of control due to excessive speed. He said with a look of reverence, "If I didn't want to give those guys at school a surprise and was afraid of being exposed prematurely, I would have liked to take a picture and post it on social media."

"Top speed, Mach 0.85."

Lin Dong ignored the conversation between the three, glanced at the detailed parameters of the engine and fuselage, reduced the speed to Mach 0.7 and began to return to base.

Mach 0.85 is not yet the thrust limit of the two engines, but it has reached the limit of the fuselage aerodynamic layout. Any higher and a stall may occur.

As for the remaining aspects such as range, maneuverability, and avionics, these cannot be tested in a short period of time.

Let's go home and have dinner first, and we can do the testing later tonight.

Rumble!

Less than an hour later, the roar of aircraft filled the sky.

Two blue trails of flame descended from the horizon, glided for nearly a hundred meters across the test track, and then made a turn and came to a steady stop at the entrance of the laboratory.

"Go check it out quickly!"

As soon as the model aircraft came to a stop, before the residual heat from the engines could dissipate, Wang Rui shouted and grabbed a powerful flashlight, rushing over to check the engines' vents.

Lin Dong also walked over, picked up a hammer and tapped the model airplane a few times. After listening carefully for a while, he nodded to Zhang Yue, who had followed him with a nervous expression.

"The craftsmanship and technology are very stable. There is no deformation or abnormal noise in the body. With your skills, you can graduate now."

"Thanks!"

"Thank you, TVXQ!"

Upon hearing Lin Dong's words, Zhang Yue, whose hands were covered in small wounds from working day and night on parts processing and refining techniques for the past two weeks, suddenly had tears welling up in his eyes.

Looking at the model aircraft with a wingspan of over two meters standing steadily at the test site, he was unsure whether to be excited or choked up: "It's all thanks to your excellent design; you considered every single detail."

"I won't take credit for that."

Standing next to the model airplane, Lin Dong compared his own thin arms and legs to those of a primary school student: "I brought it into this world, but you brought it into reality."

After more than six months of study, Lin Dong has gained a deep understanding of the entire aircraft manufacturing process.

For any aircraft, design is only the first step.

Without sufficient industrial strength and technological capabilities, even the best design is just empty talk.

Especially for subsonic and above-speed aircraft.

Because the fuselage needs to withstand strong air resistance, the internal parts and structures also need to withstand strong high-speed overload and torsion.

If even one component is not manufactured properly, the entire aircraft could be torn apart by the air.

Or, if the torque wasn't applied correctly during final assembly, the fuselage components might not be able to withstand the powerful torsional overload and disintegrate in mid-air.

This is why Lin Dong emphasized that he brought the model airplane to the world, while Zhang Yue brought it into reality.

"alright."

Lin Dong put away his notebook and instructed Cai Wei and the others: "The inspection is fine. You can push the model aircraft back to the lab. Don't lock the door. I'll come over and test the remaining range, maneuverability, and avionics performance by myself later."

"what!"

Upon hearing this, Cai Wei was stunned: "Dong Shen, you're testing alone? You don't need us anymore?"

"Dong Shen, don't do this..."

Wang Rui, who had just stayed up all night testing the aircraft, poked his head out from the engine bay of the model plane with dark circles under his eyes and said, "I can stay up all night again!"

"Still staying up all night... Summer vacation is almost twenty days over, aren't you guys planning to design and build the combat aircraft model for the September competition?"

Lin Dong looked at the two of them strangely: "Or do you want to use my model airplane in the competition?"

"But can you answer my questions about the technical details of this model airplane clearly? Won't that be considered cheating?"

What?

Wang Rui and Cai Wei exchanged a glance, their eyes widening as they said, "We've both forgotten about this."

For the next two weeks, I need to help build Lin Dong's model airplane while also completing the learning tasks set by Lin Dong.

They were so busy eating that their minds didn't stop for a moment, and the school's model airplane competition was long forgotten.

"We're doomed."

After thinking about it carefully, Cai Wei said somewhat devastatedly, "I can design a first draft of a canard-layout fuselage now, but I haven't passed the basic theory test."

The problem is, we don't have a wind tunnel.

How can we verify the rationality of the aerodynamic layout and eliminate any defects or loopholes?

In normal aircraft design, designers first provide a first draft, then build a model and test it in a wind tunnel. Based on the wind tunnel data, they then improve the design to arrive at a second version.

If you're a top-notch tech expert, this process might involve one first draft and then the final draft.

If the technology is not good enough, the first draft may need to undergo three to five wind tunnel tests, taking several months in total.

The ability of someone like Lin Dong to complete the verification of the entire aerodynamic design without even needing a wind tunnel, relying solely on his knowledge of aerodynamics and fluid mechanics and using only his brain, is a miracle belonging to geniuses, not to ordinary people.

"I also feel it's not going to work."

Wang Rui was also a little guilty at this point, and analyzed on his fingers: "After studying so hard for the past half month, I should have no problem designing a small turbofan with ordinary performance."

However, the thrust-to-weight ratio of small turbofans generally exceeds 8; those below this cannot be called small turbofans.

This thrust-to-weight ratio means that the combustion chamber and turbine must withstand extremely high temperatures and pressures, and we simply cannot find materials that meet this requirement.

Engine thrust-to-weight ratio refers to the ratio of engine weight to thrust.

The higher the thrust-to-weight ratio of an engine, the stronger its performance, and the higher the maneuverability of the aircraft it carries.

A thrust-to-weight ratio of 8 is already top-tier, meaning that a 200-kilogram engine must generate 1600 kilograms of thrust, and every component inside the engine must withstand enormous pressure and temperature.

"If you don't have a wind tunnel, just build one yourself. You don't need supersonic design. A subsonic wind tunnel can be made with a high-power axial fan."

"If we don't have nickel-based high-temperature materials, then we'll change the engine design. It's no problem to keep the engine's power-to-weight ratio at 7."

Lin Dong said calmly, "I looked up the model airplane competition at Northwestern Polytechnical University. It mainly tests students' knowledge and practical skills, not model airplane racing."

While your classmates are still using electric ducted jet model airplanes or turbojet engine model airplanes, you're pulling out canard layouts and turbofan engines.

As long as your model airplane can successfully take off and fly around without crashing, first place is yours for the taking.

I'm going back to eat now.

Take your time to think about the design. If you have any questions, come ask me tomorrow.

Done.

Lin Dong ignored Wang Rui and the others, waved, and left the test site.