The Long March 7, which is carrying out the Tianzhou-2 launch mission, stands on the launch tower and is ready to depart. In May 2021, Xinhua Society released a portrait of Cheng Tangming. If Zhang Wuchang said that the Tianzhou cargo spacecraft is a space courier, providing equipment and materials for the construction and operation of the Chinese space station in orbit, then the Long March 7 carrier rocket is a "freight train" carrying the "Tianzhou courier", specifically responsible for escorting it to the space station. As the chief designer of Long March 7, I have never relaxed or slackened off in recent years. Together with other team members, I have overcome difficulties and strive for excellence to ensure the completion of the glorious mission of direct delivery to the space station. In early 2021, I was appointed as the chief designer of the Long March 7 carrier rocket after successfully overcoming difficulties. At that time, the key technology verification and construction phase of China's space station project was about to be implemented, attracting worldwide attention. At the end of April of that year, the Tianhe Core Module of the Chinese space station was successfully launched, followed by the Tianzhou-2 cargo spacecraft. Its mission was to carry consumables, extravehicular spacesuits, and platform supplies for three astronauts, and to conduct space rendezvous and docking with the Tianhe Core Module, laying a solid foundation for subsequent flight missions and the continued construction of the space station in orbit. The rocket used to lift the Tianzhou-2 cargo spacecraft into space and complete its mission is the Long March 7. This means that the relay rod for the construction of the Chinese space station in orbit has been handed over to us. Tianzhou-2 is the first "visitor" to the Tianhe core module, and the significance of this launch mission is very significant, and every effort must be made to ensure success. Our team has full confidence in this matter. However, unexpected troubles still arose. Shortly after the launch time window was determined to be "early morning on May 20, 2021", an abnormal data suddenly "popped up" while carrying out operations such as kerosene injection, liquid oxygen pre cooling, and high flow injection according to the program, causing the atmosphere on site to immediately become solemn. What kind of problem has arisen at this critical moment when the arrow is on the line? What is the root cause of the problem? We are extremely anxious! After on-site discussion and analysis, we believe that there may have been a leak in the tail cabin. So, I immediately arranged for the test team to enter the tail compartment of the arrow body for investigation. However, the rocket has been filled with over 500 tons of propellant, and the temperature in the aft cabin is low, the space is narrow, and it is filled with nitrogen. Personnel entering the cabin must wear breathing masks, making it not only very difficult but also very risky to find the leak point. The condensed water on the outer wall of the arrow was splashing, and time passed by minute by minute. We missed the time window and had to stop firing and aim for the next day's time window. The construction of a Chinese space station in orbit is a major project that has attracted worldwide attention, with related tasks intertwined. If the malfunction of the Long March 7 spacecraft cannot be resolved in a timely manner, the Tianzhou-2 spacecraft will not be launched as planned, and all subsequent missions will be affected. In such an environment and background, it is imaginable how much pressure we were under at that time. We withstood the pressure with a strong will and worked tirelessly and tirelessly at the launch site, continuing to carry out troubleshooting and positioning. The rear of Beijing is also brightly lit, and experts stay up all night to help us diagnose our pulse. After unremitting efforts from all parties, I