According to China Aerospace Science and Technology Corp (CASC), China conducted the debut flight of its Long March 8A carrier rocket on Feb 11, transporting a group of satellites to space.

A Long March 8A carrier rocket blasts off at 5:30 pm on Feb 11 from the Wenchang Space Launch Site, Hainan province. YUAN CHEN/FOR CHINA DAILY

As the debut of China's new-generation Long March rocket, the success of the Long March 8A is of great significance. Equally remarkable was the maiden flight of the newly developed YF-75DA expander cycle hydrogen-oxygen engine, designed by the Xi'an-headquartered Academy of Aerospace Propulsion Technology of CASC.

The Long March 8A, a new addition to the Long March family, features a two-and-a-half-stage configuration consisting of a core first stage, a core second stage, and two boosters. For this launch, the Academy of Aerospace Propulsion Technology provided four YF-100 kerosene-liquid oxygen engines, two YF-75DA hydrogen-oxygen engines, and an auxiliary power system.

The YF-75DA engine boasts a more than 10 percent increase in thrust compared to its predecessor, the YF-75D. The academy's research team optimized structural and system designs, conducted extensive simulations and verification tests to ensure reliability, and enhanced the thrust-to-weight ratio, significantly improving payload capacity.

The team implemented design optimizations to tackle challenges such as prolonged pre-launch standby and re-ignition, improving low-temperature valve stability. The engine was also fortified against Hainan's humid climate to ensure operational stability under extreme conditions.

With the Long March 8A in operation, the academy continues to drive innovation in thrust augmentation, closed-loop pressurization, and maintenance efficiency, propelling China's next-generation rocket technology to new heights.