Spreading youth in the bright starry sky: the astronauts behind the Tianzhou-6 cargo spacecraft

Coconut trees, beaches, and waves. Amid the trembling of the earth, the reflection of flames, and the cheers of the crowd, the Long March 7 Y7 carrier rocket carrying the Tianzhou 6 cargo spacecraft soared into the deep night sky, flying farther and farther, and finally turned into a small point of light, blending into the bright starry sky.

On May 10, the Tianzhou-6 cargo spacecraft was successfully launched at the Wenchang Space Launch Center in Hainan, marking the first flight mission of my country's space station application and development stage. In this mission, the Eighth Academy of China Aerospace Science and Technology Corporation was responsible for the development and production of key products such as the cargo spacecraft propulsion module assembly, docking mechanism, solar cell wings, measurement and control communications, and cable networks. The successful completion of the mission is inseparable from the aerospace workers who silently dedicate themselves to their respective positions and spend their youth in the bright starry sky.

“Every mission is not a simple repetition”

Qian Jiacheng, Di Qiaoyue, Wang Yifan, Wu Xiaonan... Among this group of young people born after 1995 and 2000, many are "old astronauts" who have participated in more than three launch missions. After completing a series of tests on the propulsion module in Beijing, their task is to escort the Tianzhou-6 propulsion module from the Beijing factory all the way to the Tianjin dock, and then load it onto a ship and transport it to the Wenchang Space Launch Center in Hainan.

"In the past, cabins were transported in a horizontal state, which required some extravehicular equipment to be dismantled and transported separately, and then installed and tested after arriving at the launch site. This time, we have developed a new product packaging box, using a vertical transportation method of road + sea transportation. Except for the solar wing products, all other extravehicular equipment is transported with the cabin, which can reduce the workload at the launch site." Qian Jiacheng said proudly.

In his and his friends' eyes, this set of brand-new product packaging boxes is the "new wedding dress" of the Tianzhou-6 propulsion module. The "new wedding dress" is a luxurious space of 96 cubic meters made of aluminum alloy, equipped with a measurement and control system, a vibration reduction system, and an automatic filling and exhaust system, which tests the temperature, humidity, pressure, vibration, and impact data in the box at any time to ensure the most comfortable transportation environment for the "baby" being transported.

Before the "baby" was officially shipped, in order to fully verify the performance of the "new wedding dress", they also placed the Tianzhou-1 prototype product in a packaging box and drove from Beijing to Tianjin for a sports car test. The drive took a full 7 hours. The product testers on the car monitored the environmental conditions in the packaging box at all times and stopped every 3 hours for a comprehensive inspection.

There are 2 air conditioners and 4 electric fans in the packaging box. Why do we need electric fans when we have air conditioners? This is because the box needs to be filled with nitrogen during transportation to ensure that the air pressure inside the box is greater than the external pressure, effectively preventing marine salt spray from entering the packaging box and corroding the products. The electric fans are installed to ensure that the nitrogen can be evenly distributed in the box.

"Since joining the company in 2021, I have caught up with the construction phase of China's space station. The launch missions are intensive. Within two years, I have participated in one manned spacecraft mission and four cargo spacecraft missions. I dare not forget my master's instructions at any time. Every mission is not a simple repetition!" Qian Jiacheng said.

"Success does not equal maturity, and maturity does not equal reliability"

From Tianzhou-1 to Tianzhou-6, the docking mechanism and power subsystem of the cargo spacecraft were all developed by the Eighth Academy, and can be called "mature products" in the aerospace industry.

"As of Tianzhou-5, the docking mechanism of the cargo spacecraft has docked 11 times in total. Among them, Tianzhou-1 was the first appearance of the 2.0 version of the docking mechanism, docking 3 times, verifying the on-orbit propellant replenishment technology; Tianzhou-2 docked the most times, 4 times; Tianzhou-5 was the fastest rendezvous and docking, breaking the record of 6.5 hours of Tianzhou-1, and completed the rendezvous and docking with the space station in just 2 hours." Yang Shengxi, deputy chief designer of the docking mechanism of the 8th Academy 805 Institute, listed them all. "Success does not mean maturity, and maturity does not mean reliability."

The product is set up and confirmed before shipment, unpacked and inspected after long-distance transportation, and its status and functional performance are tested one by one... The work is trivial and ordinary. In order to do these tasks well, 805 holds risk drills before each major node, matching each operation, inspection, and password one by one. Only by carefully completing each test, accurately confirming each password, and clearly interpreting each data can we be 100% confident in our products.

100% peace of mind is the lifelong pursuit of all astronauts. The power supply system is related to the energy supply of cargo spacecraft. At the Wenchang Space Launch Center, the team also carried out a series of "redesign, re-verification, and re-confirmation" work on reliability, safety, and risk control.

Inside the factory, Huang Zheng, Liu Junjie, Chen Cheng and other designers carefully pushed a lighting stand with rows of bromine tungsten lamps installed on it. They used the light source of the bromine tungsten lamps to illuminate the solar panels installed on the unfolded brackets. With light, the solar panels will generate electricity. A cable was connected to the test equipment, and Wang Jiawei, a power subsystem designer, carefully confirmed the status of the solar cell circuit of each panel.

Yao Xiaofeng, a solar panel inspector, has been engaged in the inspection and precision measurement of solar panels for more than 30 years. She climbs up and down to measure the precision of each solar panel. Every time the cabin is assembled and inspected, she uses a lift to rise several meters in the air for final confirmation.

"Inspectors need to check every step carefully, have a serious work attitude and meticulous work habits, so that products can be safely sent into space," said Yao Xiaofeng. When she talked about the products, she was as proud and reluctant to part with them as if she were talking about her own children.

Generation after generation of boat makers continue to pursue their dreams

From Tianzhou-1 to Tianzhou-6, the cargo spacecraft propulsion modules were all assembled by Factory 149 of the Eighth Academy. Here there are assembly helmsmen born after 1975, quality gatekeepers born after 1985, and young newcomers born after 1995. Generation after generation of "boat" builders have continued to strive for their dreams of space.

Cheng Dagang, born in 1975, is the general assembly leader of the propulsion module of Tianzhou VI. He has participated in more than 30 general assembly and test missions of Shenzhou, Tiangong and Tianzhou. He has the skills in his hands and the responsibilities on his shoulders. In this Tianzhou VI mission, in order to cooperate with the sealing state transformation of the rear cone section of the cargo module, dozens of equipment were adjusted to the propulsion module, which brought considerable challenges to the general assembly work in the module.

Cheng Dagang suddenly had an idea: Can we build a "scaffolding" in the cabin like building a house? With an idea in mind, he immediately started to work. He and the technicians discussed the installation methods of the "scaffolding" again and again, installing one horizontally, one vertically, and another one using the cabin body... After rounds of verification and improvement, a set of horizontal cabin entry tooling composed of multiple parts that can be freely combined was born, which perfectly solved the equipment operation requirements at the extreme position in the cabin.

Miao Yinshan, born in 1985, is the gatekeeper of quality. Before each important assembly work, he would organize technicians, inspectors, and operators to conduct on-site simulations to familiarize themselves with each key operation step and identify potential operation risks. In his mind, simulation work is a process of deepening, refining, and becoming more proficient. It is also the last "performance" without physical objects, ensuring that the formal operation is foolproof.

"Details determine success or failure. We always treat every spacecraft as its first spacecraft, and use a rigorous, meticulous work style and a thoughtful and careful work attitude to provide a protective umbrella for the product." said Miao Yinshan.

With a courageous curiosity to explore, Wang Yifan, born in 1995, quickly grew into a young rookie who can stand on his own feet. Understanding the source of products is his "secret". From single instruments to cable pipelines, from structural spray painting to thermal control multi-layers... he is often seen. Through "follow-up" learning, Wang Yifan became familiar with the collaborative production process of various departments, promoted the linkage of "design-process", and established a product assurance awareness based on design requirements.

Focusing on the product itself is his "heavy punch". "Now the spacecraft assembly has been upgraded from two-dimensional drawings to three-dimensional models, which requires us to have a pair of perspective eyes to better transform the design documents into operable structured processes." Wang Yifan said. He and his team developed a number of equipment for the cabin, including large-capacity packaging boxes and automated assembly operation platforms, to ensure the orderly progress of the assembly work.

The starry sky is vast and endless, and exploration is endless. Sailing on the Tianhe River, Chinese astronauts are moving forward courageously! (Reporter Zhang Jiansong)

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