November 23, 2021 07:45

Long March 4C Carrier Rocket

blasts off from the launch pad at Jiuquan Satellite Launch Center

transporting Gaofen-3 02 satellite into the scheduled orbit

gaining a successful launch

Long March 4C Carrier Rocket

The Long March 4C carrier rocket used for this launch mission is a three-stage liquid carrier rocket functioning at normal temperature generally developed by the Eighth Institute of China Aerospace Science and Technology Corporation. Boasting excellent performance and a wide range of applications, it can launch a variety of satellites with different requirements about orbits, and it can perform one satellite launch as well as multiple satellites launch, with the carrying capacity of its sun-synchronized circular orbit reaching up to 3 tons (orbit height of 700 kilometers).

In mid-October, the outbreak of COVID-19 in Ejina Banner, Inner Mongolia posed a serious problem for the upcoming pilot team. Jiayuguan, Lanzhou, and Xi'an, which were the focal points of the outbreak, happen to locate on the only way to the launch site. In order to take into account both health and safety and task deadlines, the Eighth Institute braved the elements and managed to let the pilot team fly directly to Jiayuguan by chartered plane. On the day of departure, the pilot team of Chang-4 model leaving for Taiyuan happened to be there too. The two teams came across each other at the airport and made a high-five. "The soldiers are divided into two groups, watching and helping each other, working together, and looking forward to victory and reunion!" On November 20, a good news came from Taiyuan, revealing the complete success of the Long March 4B rocket. In just three days, another success was achieved in Jiuquan. Both teams have fulfilled their promises.

During the mission, with strict epidemic prevention and control requirements, the pilot team completed multiple rounds of nucleic acid testing and three-day isolation as required upon arrival at the base, and then began to implement the "dormitory to factory" two-point, one-line prevention and control policy. Such living conditions are monotonous and boring, however, the pilot team managed to use the conditions to plan and carry out "double thinking" and review work. The team members initiated work at the launch site wearing isolation protective clothing. "Da Bai", the first team of the technical zone plant completed the recovery of the arrow body unloading, creating a beautiful scenery. Zhang Cheng, the general professional designer of the model, said with emotion: "We are extremely honored to be one of the heroes in harm's way, and also sense a more huge responsibility. Nevertheless, everyone in the team is motivated, and there is no difficulty that we can't conquer.

This mission uses the launch site quality confirmation system, which is also the first time for the model to use the PAD terminal as a confirmation system tool at the Jiuquan Satellite Launch Center. Before entering the site, the model has planned to form a complete set of quality confirmation forms, accurately decomposing the 325 tasks in the whole process, compacting them to 26 positions, realizing the integration of "technology, production assurance, and planning" at the launch site. Ever since the first workday after entering the site, all positions have strictly followed the planned projects and standards to carry out relative work and confirm the results. The pilot team has meetings on a daily basis to finish tasks and advance work in a timely manner. It is the careful planning and strict implementation that enable the various tasks of the model to further smoothly without any disturbances.

This mission is equipped with a relay user terminal system, which uses a relay satellite to receive the rocket's active phase telemetry signal and transmit information. Compared with traditional ground-based measurement and control methods, relay measurement and control is not affected by the layout of the ground stations, less restricted by the rocket launch trajectory design, and greatly extends the receiving period of rocket signals, especially for the long-range Long March 4C rocket with longer active phase. The advantages are very obvious. It is also the first time that the model has used this technology in the Jiuquan Satellite Launch Center. The pilot team has conducted adequate interface coordination, technical disclosure and ground testing with the launch site, so as to ensure product quality control and smooth flight assessment.

In addition, in order to better observe the satellites separated from the rocket, the pilot team has made a reasonable design of the time sequence of the rocket discharge section based on the relative positions of the satellites and the rocket as well as the field of view of the imaging system, and timely adjusted the attitude of the rocket, so that the rocket image can observe the key actions of the satellites such as the stretching of wings in a staring state after the separation, greatly improving the observation effect and providing high-quality intuitive information for determining the initial state of entering the orbit.

The Gaofen-3 02 satellite launched this time was generally developed by the Fifth Institute of China Aerospace Science and Technology Co., Ltd., which could meet the measurement needs of users in marine, emergency, land, geology, environmental protection, water conservancy, agriculture, meteorology and other industries.

It is the 81st launch of the Long March 4B series carrier rockets, the 147th launch of the Long March series carrier rockets generally developed by the Eighth Institute, and the 398th launch of the Long March series carrier rockets.