- The common-bulkhead tank is a key component of the company’s reusable Nebula-2 rocket, which is designed to carry up to 25 tonnes to low Earth orbit
- The milestone advances development of a launcher built for lower-cost manufacturing and more than 20 reuses
Chinese reusable rocket builder Deep Blue Aerospace (深蓝航天) has completed what it says is China’s largest stainless steel common-bulkhead rocket tank, measuring 5 meters in diameter.
The tank is designed for its Nebula-2 reusable rocket, marking a step forward in the launcher’s engineering development as Chinese commercial space companies work to expand launch capacity.
The company, based in Wuxi, Jiangsu Province, announced the milestone on October 12. The tank is a key structural component of the large liquid-fueled rocket, and its completion lays the groundwork for further propulsion-system testing.
Built for mass production
Rocket tanks are among the main load-bearing structures of a launch vehicle, storing propellants while withstanding the stresses of flight. Their manufacturing speed and cost can directly affect how quickly a rocket can be delivered.
Deep Blue Aerospace is adopting stainless steel, a material also used by SpaceX’s Starship program and other rocket developers.
Compared with traditional aluminum-alloy tanks, stainless steel can reduce reliance on large, specialized tooling and may simplify manufacturing. Its strength and ability to withstand extreme temperatures can also reduce the complexity of thermal protection, depending on the vehicle’s design.
The company said it used an iterative development process, advancing design, manufacturing processes and production in parallel to complete the tank. It described the achievement as a new milestone for large stainless steel rocket tanks in China’s commercial space sector.
A reusable heavy launcher
Nebula-2 is designed to carry 25 tonnes to low Earth orbit (LEO) and 18 tonnes to a 500-kilometer sun-synchronous orbit, according to the company. LEO generally refers to orbital altitudes of about 200 to 2,000 kilometers and is widely used for satellite internet constellations.
The rocket is designed for more than 20 reuses and will use a tower-based capture system similar to SpaceX’s “chopstick” method, which catches a returning booster near its launch site rather than requiring a separate landing platform.
Deep Blue Aerospace also revealed Nebula-2’s planned exterior finish: a silver-gray metallic appearance that preserves the stainless steel’s natural texture instead of using conventional white paint.
Next steps
The tank’s completion provides a foundation for a second-stage propulsion-system test planned by the end of this year. Development of the first-stage tank and testing of the first-stage propulsion system are also in the pipeline.
For reusable rockets, a large tank is only one part of the challenge. The broader goal is to manufacture vehicles quickly, recover them reliably and turn them around for repeated launches. Nebula-2’s upcoming tests will help show how far the company has progressed toward that goal.
Header image credit: Deep Blue Aerospace
