September 13th, New York.
Zhao Chen was looking through the LME nickel plate inventory distribution details submitted by Lin Shicheng in the office of Era Vanguard, and the screen of his mobile phone lit up.
The caller ID is a California number.
He picked it up, and the voice of Elon Musk came from Fremont. There was the intermittent hum of power tools in the background.
"Zhao, have you been at New York lately?"
"Yes. Come and deal with some Era Vanguard matters."
"Come to Boca Chica. September 15th.
The vacuum version of the Raptor has just run the full duration test on McGregor, and the SN8 ring sections have been piled up in the factory.
Three Raptors will be installed for static ignition in October, followed by high-altitude test flights. Come and take a look."
Zhao Chen Change the phone to the other ear.
Elon Musk's tone is different from usual--
He never invited anyone with the phrase "come and see", he would only say "you should come" or "there's something here you need to see".
But this time he said "come and take a look", with something close to eagerness in his tone that he didn't even deliberately conceal.
That's the eagerness that would only appear in a person who spent a whole year welding stainless steel ring segments into Starship.
"What time is it on the 15th?"
"Two o'clock in the afternoon. I'll ask my assistant to arrange a car for you. Don't bring too many people, the factory is very crowded."
Zhao Chen hung up the phone and sent messages to Su Wantang and Shen Zhiyi.
On the morning of September 15th, three people flew from New York to Brownsville.
The driver arranged by Lin Shicheng held a sign with no words at the airport exit - only a black "Z" was printed on it.
The car drove east from Brownsville onto the road leading to Boca Chica.
September in the southern end of Texas is much hotter than that in New York. The bushes outside the car window are turned gray-green in the sun.
At the end of the horizon, you can see low-hanging clouds in the direction of Gulf of Mexico.
Su Wantang is sitting in the back row, holding an agenda for the Foundation remote coordination meeting.
But her eyes fell on the SpaceX signs that occasionally flashed by the window.
Shen Zhiyi is sitting in the passenger seat with a laptop on his lap.
On the screen is a list of cross-border legal affairs docking between Era Vanguard and Henglong.
But she wasn't looking at the screen either. Instead, she turned her head and looked at the outline of Launch Site getting closer and closer outside the window.
Zhao Chen was sitting in the back row on the other side, with Zisha Pot's soft cloth bag on his lap, which was not opened.
When the car drove into the Boca Chica base, the first thing that came into view was not the transmission tower, but a row of huge white tent-style factory buildings--
SpaceX's Starship production base in southern Texas.
The parking lot in front of the factory was filled with pickup trucks and a black Model X that looked like it hadn't been washed for a long time.
Zhao Chen recognized that car at a glance - Elon Musk drives this car every time he comes to Boca Chica.
"Zhao."
When Elon Musk walked out of the factory, he was wearing a washed gray T-shirt with a loose collar. There were oil stains and a few scratches on it.
His hair is longer than when we last met at Boca Chica, and his stubble is thicker. He looks like he has lived in a factory for several days.
He strode over and shook Zhao Chen's hand with the same strength as before.
"You're just in time. The vacuum version of the Raptor completed a full-time test yesterday at McGregor. I'll show you the video later."
Zhao Chen handed Zisha Pot's soft cloth bag to Su Wantang, and followed Elon Musk towards the factory.
Shen Zhiyi and Su Wantang were led to the reception area by a SpaceX engineer, and Zhao Chen followed Elon Musk through two rows of huge stainless steel ring sections--
Those are the cylinders of the Starship prototype machine that is being assembled. Each section is several stories high, and the welds glow with a silver-gray cold light under the factory ceiling lights.
"SN8."
Elon Musk patted one of the stainless steel cylinders and made a dull echo.
"Three Raptors, nose cones, aerodynamic surfaces, everything.
We will bring it to the launch pad in early October and do static ignition on three rounds first. If there is no problem with static ignition, then--"
He stretched out a hand and made a motion of sliding down from a high place and then turning it up again.
"Belly-flop. Somersault back, raising your butt at the last second.
If this can be done, it will be the craziest rocket gymnastics since Falcon 9 landed."
Zhao Chen Look at those stainless steel ring segments.
More than two years have passed since Boca Chica first met Starworm Prototype.
At that time, Starworm was like a silver-gray water tower, so rough that it could be blown down by a gust of wind at any time.
The current SN8 already has a complete rocket body structure, aerodynamic surface and nose cone. Standing between these huge ring segments,
You can feel that the entire factory is like an iron-gray beast that is waking up.
Elon Musk led him to a workbench in the corner of the factory.
There is an open laptop and a projector on the countertop, with several cut-out Raptor engine parts stacked next to it--
Combustion chamber, nozzle, turbine pump, each section is marked with dense dimensions and tolerances.
Elon Musk typed a few times on the computer, and a video popped up on the Projection Screen cloth.
On the McGregor test bench, a Raptor engine sprayed out an almost transparent blue flame, which lasted for nearly fifteen seconds, and then shut down smoothly.
"The vacuum version. It was officially announced to the public on September 25th, but the full run was completed yesterday."
Elon Musk tapped the nozzle section of the engine on the screen with his finger.
"The nozzle area is much larger than the sea level version and is specially optimized for vacuum.
The sea level version reached a combustion chamber pressure of 330 bar in August this year - 330 bar, 225 tons of thrust.
The previous best record was 268.9 bar by Russia RD-180, and later it reached 300 bar by RD-701.
Now we are number one."
Zhao Chen looked at that video.
The blue flame burned on the test bench for fifteen seconds, and the engine was intact.
He had seen the numbers in the tweet sent by Elon Musk before - 330 bar, 225 tons of force.
But now, standing in the factory of Boca Chica, watching this unpublished test video, the feeling is completely different from watching the data.
The engine had grown from a drawing in the team of the man in the gray T-shirt in front of him.
"330 bar, intact after shutdown. What is the significance of this number in engineering?" Zhao Chen asked.
Elon Musk paused the video at the frame of the engine nozzle, turned around and leaned on the table, crossing his arms on his chest.
When he answered, he spoke a little slower than usual, as if to confirm that the other party really wanted to hear technical details instead of being polite.