At 17:30 pm on February 11, 2025, the Long March 8A carrier rocket was successfully launched from the Wenchang Space Launch Site. The following is a detailed introduction to the Long March 8A launch vehicle:
1. Basic information
The Long March 8A launch vehicle is a medium-sized liquid launch vehicle developed by the First Academy of Aerospace Science and Technology. Compared with the Long March 8, the Long March 8A launch vehicle is equipped with a universal hydrogen-oxygen final stage and a larger diameter fairing, which makes up for my country’s urgent need for low-orbit giant constellation network launches in the future. The Long March 8A launch vehicle has a two-stage and a half configuration, with two boosters, a core diameter of 3.35m, a booster diameter of 2.25m, a height of 50.539m, a mass of about 371t, and a sun-synchronous orbit payload (700km) capacity of about 7t. The Long March 8A carrier rocket can be launched from Station 201 of the Wenchang Space Launch Site and Station 1 of the Hainan Commercial Space Launch Site.
2. Rocket composition
(1) Fairing
The Long March 8A is suitable for fairings with a diameter of 4.2m and 5.2m. The length of the fairing with a diameter of 5.2 is 13m.
(2) Core level one
The first stage of the Long March 8 core is 3.35 meters in diameter and is equipped with two YF-100 engines with a thrust of 120 tons. YF-100 uses liquid oxygen and kerosene as propellants, adopts an oxygen-rich pre-ignition staged combustion cycle, the mixing ratio is 2.6, the sea level thrust is 124.8t, the sea level specific impulse is 300s, the vacuum thrust is 136.7t, and the vacuum specific impulse is 335s.
(3) Core level two
The Long March 8 core has a secondary diameter of 3.35 meters and is equipped with two YF-75H hydrogen-oxygen engines with a vacuum thrust of 10 tons. The YF-75H is an improvement based on the YF-75D. It adopts a closed expansion cycle and has a thrust of 10 t at sea level.
(4) Booster
The Long March 8A is bundled with two 2.25-meter-diameter liquid boosters, each booster is equipped with a YF-100 engine with a thrust of 120 tons.
3. Rocket characteristics
The second stage of the basic version of the Long March 8 basically uses the third stage of the Long March 3A series. However, when used on the Long March 8, the scale was too small, which seriously affected the transportation capacity. The Long March 8A developed a new universal hydrogen-oxygen final stage, increased the diameter of the rocket body, and increased the fuel filling volume. In addition, the second stage was also replaced by the YF-75H with greater thrust. Through a series of improvements, the transportation capacity of the Long March 8A was greatly improved.
