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Published on: G

July 21, 1969

11:34 PM Italian time: The LM piloted by Neil Armstrong has difficulty docking. It immediately goes into gimbal lock (the inertial platform with the gyroscopes locks mechanically). This means the system becomes automatically uncontrollable. The Geminis couldn’t have gimbal lock because they had a fourth degree of freedom to avoid it, but the designers, suffering from NIH (Not Invented Here) status, ignore the innovation and use the classic inertial platform. Neil switches to the AGS (Abort Guidance System) and guides with the alternative manual system, managing to bring the situation under control.