On April 15, 2025 (today), the 100th “Tianque” series liquid oxygen methane rocket engine of Blue Arrow Aerospace Technology Co., Ltd. officially rolled off the production line. As the world’s first commercial aerospace company to successfully put a liquid oxygen methane rocket into orbit, Blue Arrow Aerospace has independently developed the “Tianque” series of liquid oxygen methane rocket engines, which provides a key power core for the development of reusable rockets. The rollout of the 100th liquid oxygen methane rocket engine not only means that Blue Arrow Aerospace has become my country’s first private aerospace enterprise with the capability to develop 100-level liquid oxygen methane rocket engines, but also marks that my country’s commercial aerospace power industry has entered the stage of large-scale application. The following is part of the research and analysis of the “Tianque” series of liquid oxygen methane rocket engines:
1. Tianque-11
Tianque-11 is a pump-back swing gas generator circulating high-altitude liquid oxygen methane rocket engine. It has the ability to start twice and is divided into two states: main engine and cruise engine. The main engine status is 1 combustion chamber, and the nozzle area ratio is 100. In the host state, the vacuum thrust is 8.8 t and the vacuum specific impulse is 357 s. The traveling engine adopts a single-pump four-combustion chamber design with a nozzle area ratio of 25.5. In the idle state, the vacuum thrust is 8.2 t and the vacuum specific impulse is 333 s. During the development process of Tianque-11, hydrodynamic sealing technology was applied to the engineering development of liquid oxygen methane rocket engine for the first time to improve the reliability of the engine.
2. Tianque-12
Tianque-12 is a pump-back swing gas generator circulating liquid oxygen methane rocket engine that uses autogenous supercharging. Each single engine swings in one direction, the swing direction is tangential to the rocket body, and the swing angle is ±8°, which can provide attitude control in all directions for rocket flight. Tianque-12 is installed in the first stage of Zhuque 2, with a sea level thrust of 658.5 kN, a sea level specific impulse of 286s, and a single pendulum engine. The Tianque-12 vacuum type is installed on the second stage of the Zhuque-2, with a vacuum thrust of 776.5 kN, a vacuum specific impulse of 337s, and a fixed engine. Tianque-12 is a milestone as the world’s first methane-powered engine for orbital flight. However, due to its smaller thrust compared with engines of the same class, mediocre specific impulse performance, and low thrust-to-weight ratio, it dragged down the capacity of the early version of the Suzaku-2 to a certain extent. In order to solve the shortcomings of the engine, Blue Arrow Aerospace developed improved Tianque-12A and Tianque-12B based on Tianque-12.
3. Tianque-12A Tianque-12A is a pump-back swing gas generator circulating liquid oxygen methane rocket engine with a reusability of more than 10 times and a thrust adjustment range of 45% to 111%. Tianque-12A fully inherits Tianque-12 and through design optimization and improvement, the engine thrust is increased by 9%, the specific impulse is increased by 40 m/s, and the weight is reduced by 100 kg. Tianque-12A has a vacuum thrust of 807kN, a vacuum specific impulse of 3160 m/s, a sea level thrust of 720 kN, and a sea level specific impulse of 2840 m/s. 4. Tianque-12B Tianque-12B is a gas generator circulating liquid oxygen methane rocket engine with a thrust of 1000 kN at sea level. Nine engines are planned to be installed in parallel on the first stage of the Suzaku-3. Zhuque 3 is a reusable large-scale liquid oxygen methane launch vehicle developed by Blue Arrow Aerospace. It uses a stainless steel rocket body and is equipped with 4 sets of landing legs and 4 sets of grid rudders. One sub-stage is recyclable and has the ability to launch multiple satellites with one rocket and flat-plate stacked satellites. 5. Tianque-15A Tianque-15A is a pump-front swing gas generator circulating vacuum liquid oxygen methane rocket engine. It uses a pump-front swing layout plan to reduce the pump-push distance and improve the compactness of the structure. Tianque-15A and Tianque-12A share key components such as turbine pumps, valves, and gas generators. Tianque-15A thrust adjustment range is 55%~110%, with three starting capabilities, vacuum thrust of 836 kN, and vacuum specific impulse of 3320 m/s. Tianque-15A is a usable vacuum liquid oxygen methane rocket engine. Its thrust is large, it has certain vector control capabilities, and it can be ignited three times, which greatly expands the launch mission range of Suzaku-2. However, because the nozzle area ratio of its early batches was too conservative, the specific impulse of its early batches was far from reaching the design specifications. 6. Tianque-15B Tianque-15B is a gas generator circulating vacuum liquid oxygen methane rocket engine. As an improved version of Tianque-15A, it has a vacuum thrust of 1183 kN and a vacuum specific impulse of 3500 m/s. It is planned to be installed on the second stage of Suzaku-3.
