Rocket engineer does all he can to ensure safety of China's astronauts

Xu Liping helps make one of the most critical parts on the Long March 2F carrier rocket that sends Chinese astronauts into space.

However, he hopes that what he makes will never need to be used during a launch. That is because it is the escape system atop the Long March 2F model that would be deployed if there was a rocket malfunction during launch and the astronauts needed to be taken safely from the rocket.

"Its only function is to pluck the mission crew from danger," said Xu, a solid-propellant rocket engine technician at the Xi'an Aerospace Chemical Propulsion Factory in Shaanxi province. "So we must be 100 percent sure that it is reliable and can work if a rocket malfunctions, so of course we hope it never needs to be used."

Xu, 53, leads a team of propellant-processing technicians at the factory, part of the Academy of Aerospace Solid Propulsion Technology that is a subsidiary of China Aerospace Science and Technology Corp. The academy supplies solid-fuel engines for Chinese carrier rockets and ballistic missiles.

The escape system, often called a mini rocket, is propelled by its solid-propellant engines, and whether those engines work well depends largely on the condition of their propellant.

The only job for Xu and his co-workers is to ensure the solid propellant is in the exact shape designed by engineers. They have taken part in making all the escape systems used in China's crewed spaceflights, and fortunately none has had to be used.

Delicate job

In fact, building an escape system has been an on-off task for the veteran Xu, who this September will celebrate 35 years of service at the factory, which he joined after he graduated from a vocational school run by the Shaanxi academy when he was 18. For most of the intervening years, Xu and his colleagues have worked on engines for use in ballistic missiles.

To the uninitiated, such work may seem far from glamorous, but the importance in ensuring that the assembly of a properly functioning missile is safe is obvious.

While a lot of what the technicians now do is automated, the most delicate procedures must still be done by hand.

Using very small tools, they carefully clean and trim the surfaces of the propellants, which are among the most dangerous materials on Earth because of their highly explosive nature, as any cracks or imperfections could lead to uneven combustion within the rocket that would cause it to deviate from its trajectory or explode in midair.

Xu and his team must always be mindful that even the smallest slip of the hand at the wrong moment could result in a devastating explosion capable of tearing themselves and the entire workshop apart.

"We must all be familiar with the propellants' traits. Our work requires an extremely high level of concentration and caution because the things we trim are highly inflammable-some kinds of propellants will ignite even if you roll a small steel ball on their surface," he said.

"Every time we enter the workshop, we put on special uniforms and make sure we are wearing nothing that could generate an electrostatic spark. When we're working with the propellants, we do so very slowly. We're thinking about nothing except the trimming procedures."

In his very first day on the job, his tutor took him to watch an ignition operation of chopped-off propellant to show him its power.

"I was very casual about it, thinking that because of the small amount of propellant, nothing much would happen, and I was dozens of meters away from the ignition site. So you can imagine my shock when the ignition unleashed an incredibly hot wave created by the rising fireball and that I could clearly feel," he said.

Such a job obviously requires many skills and a lot of patience, and each new member of Xu's team has to complete a three-year apprenticeship before being allowed to work alone.

All have gone on to become skilled technicians, said Han Shuo, a former student himself. Yet Xu, with all his years of experience, is still considered the master and is always called upon first when propellant for a newly developed rocket needs to be processed, Han said.

Role model

Xu said that whenever he and his colleagues see strategic ballistic missiles that they helped build being paraded in Tian'anmen Square in Beijing on special occasions, they feel immense pride.

In recognition of his achievements and contributions to the country's space industry, he was named a "role model of the time" by the Publicity Department of the Communist Party of China Central Committee in 2017 .

The following year, he was elected as a deputy to the 13th National People's Congress, the country's top legislature.

Wang Yajun, Party chief of the academy, said Xu is inspirational for all members of the academy, who are encouraged to learn from his complete devotion, dedication and innovation.

The academy's employees, especially the youngsters, should pursue perfection in their work as Xu always does, he said.

Thanks to the hard work of Xu and other researchers and technicians at the academy, China is moving fast in the research and development of solid-propellant engines that will be used to power the country's next generation of rockets.

Engineers at the academy have started to conduct ground tests of the world's mightiest solid-fuel rocket engine, which has a diameter of 3.5 meters, 150 metric tons of propellants and thrust of 500 tons.

Wang Jianru, chief designer of the engine, said it includes a number of advanced technologies and high-performance composite materials. With world-class capability, it will be used on the country's super-heavy rockets now being developed, he added.