Questioning

"Yifei's few self-media accounts just posted a preview, saying they're transitioning to turbofan model aircraft and will be live tomorrow."

"Didn't he already fail a transition once? I still remember that old model aircraft of his, it couldn't even fly past a ducted fan."

"I don't know about that. Maybe he found a new engine supplier or technical support."

"Holy crap, everyone go check out Yifei's preview, the bragging is out of this world."

"Straight up to 50,000 meters, holy crap, is this picture photoshopped too well!"

"Altitude 55389, speed 612 meters per second. Did Yifei's boss get hit in the head by a model aircraft?!"

"Old Zhang, aren't you pretty familiar with Yifei? Do you know what's going on? @Zhang Fei Model Aircraft Store"

"I'm not sure either. Yifei contacted me this afternoon about transferring some ducted fan model aircraft parts. I'm planning to go check them out tomorrow, I'll see the situation on site then."

Penghai City, a suburban e-commerce model aircraft factory.

Because of Chen Yi's sudden announcement, several model aircraft dealers in the factory's group chat also started a heated discussion.

Yifei was one of the first merchants in the industry.

He transitioned from drones to model aircraft and had been going strong for four years.

Chen Yi also had a certain reputation in the drone and model aircraft circles.

Although Yifei had been declining for the past six months due to channel and technical issues, some people still paid attention to Chen Yi's movements and showed basic respect.

While a group of fellow merchants were discussing Chen Yi's situation.

Jinling University of Aeronautics, sophomore dorm.

Shao Kaiwang habitually opened Shu Zhan and Chen Yi's account.

Two years ago, it was through Chen Yi's self-media account that he first learned about drones, and then further learned about model aircraft and aircraft.

Ultimately, inspired by the content of the videos, he chose Jinling University of Aeronautics for his college entrance exam.

Although after two years of diligent study, he had mastered knowledge far deeper than what Chen Yi introduced in his videos, and could even easily spot some of the pseudo-scientific knowledge errors in Chen Yi's videos.

But over the years, watching Chen Yi's videos and updates had become his habit.

However, the content Chen Yi's account updated today seemed a bit different.

"These photos and screenshots don't look photoshopped."

"But at this altitude of 55,000 meters, a turbofan engine simply can't reach it. You'd need a rocket engine with its own oxidizer."

Shao Kaiwang clicked on the preview images Chen Yi had posted, feeling completely baffled.

Because of the photos and screenshots Chen Yi had posted.

No matter how he looked at them, he couldn't find any trace of photoshopping.

But if it wasn't photoshopped.

This altitude of 55,000 meters.

Unless it was a rocket engine, a turbofan engine simply couldn't reach it.

"Whether it's real or not, we can just calculate the sun's angle."

After studying for a while, still unable to figure out if this was photoshopped or if Chen Yi's turbofan model aircraft had really flown to an altitude of 50,000 meters, Shao Kaiwang stopped worrying about it and took out paper and pen to start calculating.

Girlfriends might lie, but calculations and mathematics wouldn't.

"The screenshot parameters include the latitude and longitude, altitude, and time of the model aircraft.

With the latitude and longitude, seasonal information, and the curvature of the horizon, we can calculate the angle at which the sun, after setting, is obscured by the sea level at the current latitude and longitude during the time of the photo.

The photo also captured Venus, which is the brightest star after sunset.

Similarly, based on the season and time of the photo, we can calculate the visual distance and angle between the sun and Venus.

Then, as the line of sight rises from the sea level all the way up to 55,000 meters, the line of sight of the lens, the position of the sun, and Venus form a triangle. The interior angles of this triangle are..."

Shao Kaiwang wrote down three numbers, then saved Chen Yi's photo to his notes. Using the pen tool, he connected the sun, Venus, and the visual center point, which was the camera's position.

Without using a protractor, Shao Kaiwang could tell at a glance that these three angles were correct.

Fearing his visual estimation was wrong, Shao Kaiwang still took out a protractor, measured it several times, and then fell into silence.

The measurement results couldn't be said to be exactly the same, only that they were completely identical.

"Incredible!"

"As expected of the person who guided me into aerospace vehicles! Awesome (shouting)!"

Shao Kaiwang shouted "Awesome."

He opened a group chat for a university aircraft club he had joined and forwarded Chen Yi's preview link.

[Shao Kaiwang: Guys, I found an amazing UP主 who's previewing a turbofan model aircraft that flies straight up to 50,000 meters!]

[Luo Zehai: ???]

[Wu Ande: ???]

[Lin Weijie: ???]

[Lin Qian: Wangwang, are you still asleep? A model aircraft at an altitude of 50,000 meters?]

[Shao Kaiwang: It's true! Look at the photos and control interface screenshots in the preview. I calculated the sun's angle and the angle of Venus in the photo, and they match perfectly!]

[Shao Kaiwang: This is an uploader I've been following for years. He was my initial inspiration in the field of aircraft. The reason I enrolled in our academy to study aircraft was influenced by him.]

Shao Kaiwang uploaded his calculation process and results.

This was the first time he had introduced Chen Yi's account to his friends, and how he got to know Chen Yi.

He had thought about sharing it before, but Chen Yi's videos were just too much to handle.

No, they were too amateurish.

They were fine as simple popular science content.

But as soon as things got a little deeper or more professional, he would become vague or full of loopholes.

It made him too embarrassed to share or introduce Chen Yi to his classmates and friends.

However, now, with a turbofan model aircraft reaching an altitude of 50,000 meters, regardless of how Chen Yi accomplished this feat.

In Shao Kaiwang's heart, it was enough to shout "awesome!" and share it with his friends.

Faked?

It was impossible for it to be faked.

He believed in the integrity of the uploader he had followed for years, and he also believed in his own calculation results.

[Lin Weijie: The calculation is correct. The angles of the sun and Venus in this photo are indeed from an altitude of 50,000 meters.]

[Luo Zehai: A turbofan model aircraft reaching 50,000 meters. This is truly eye-opening!]

[Wu Ande: I thought our building a rocket from scratch was already amazing.]

[Lin Qian: I still feel something is wrong. Maybe this uploader predicted Wangwang's calculation and P-shopped the sun and Venus angles in advance.]

[Shao Kaiwang: Impossible. This uploader wouldn't fake it.]

[Lin Qian: Whether it's fake or not, we'll know tomorrow during the live stream. Didn't his preview say he'd be live-streaming a flight to space tomorrow at 3 PM?]

[Lin Qian: The weather in Jinling and Penghai is good these few days, with high visibility. Let's set up a space telescope to track it tomorrow.]

[Lin Qian: As long as the model aircraft reaches an altitude of 60,000 meters, we can track and see it in Jinling. The photos and videos might be fake, but tracking it with our own eyes is impossible to fake.]