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Back to #414 How SpaceX Works.

Why Did SpaceX Delete Falcon 9 Folding Fins?

David Senra, reading Max Olson, says SpaceX deleted the folding mechanism on Falcon 9 grid fins after simulations showed fixed fins were acceptable.

Falcon 9 grid fins were originally designed to fold like traditional aerospace grid fins. The folding mechanism reduced drag during ascent and seemed obviously necessary. SpaceX questioned whether the mass and complexity were worth it. Simulations showed fixed fins were acceptable, so the mechanism was deleted entirely. Olson quotes Elon Musk: the best part is no part and the best process is no process. Requirements from people treated as smart are the most dangerous, because nobody thinks to question them. Every requirement must have an owner, a specific person who can defend why it exists. If the owner cannot explain it, or the original reason no longer applies, the requirement gets deleted.

A team that is not adding back at least 10% of the requirements it deleted is not deleting enough.

Grokipedia·SpaceX·Falcon

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#414 How SpaceX Works ·

Founders

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