Properly designed composite pressure vessels weigh half as much as titanium
Tom Mueller · Tom Mueller: SpaceX's #1 Employee Built the Merlin Engine. Now He's Building Impulse Space · Sourcery with Molly O'Shea · Jun 4, 2026 · at 15:43
Tom Mueller, founder of Impulse Space and former SpaceX VP of Propulsion, discusses the mass advantages of composite overwrapped pressure vessels during a tour of Impulse's factory.
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“So a properly designed COPE will be about half the mass of a state-of-the-art, all metallic tank, like a titanium spacecraft sphere. The carbon's so much stronger, it'll actually be about half the weight.”
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