Why the US-China space race could come down to a thin metal cap

propellant tank dome that is only millimetres thick must withstand extreme internal pressures and is very difficult to mass-produce3-MIN READ3-MIN8ListenPublished: 9:00pm, 15 Jul 2026In the high‑stakes space race between the United States and China, the decisive advantage could come down to a metal cap that few outside the industry have ever heard of: the propellant tank dome.An ellipsoidal bulkhead several metres wide but only millimetres thick, the dome must withstand extreme internal pressures, vibration and shock. The rounded, capsule-like end cap is also very difficult to mass-produce.Whichever country can make these components faster, cheaper and more reliably will have an advantage in building the large fleets of reusable rockets needed for the future space economy.03:54The race for the moon’s south pole: can China beat Nasa’s 2028 deadline?Now, China is signalling that it may have found not one but two ways to break the bottleneck.