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Joined 6 months ago
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Cake day: April 14th, 2024

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  • 3 weeks, roughly in line with faster Space Shuttle turn around times

    The shortest shuttle turnaround time was 55 days. Almost three times as much as Falcon 9. The fastest post-Challenger turnaround time was 88 days, I believe. After Columbia, the fastest turnaround was around 5 months.

    NASA claimed that the shuttle could achieve a turnaround time of two weeks (page IX). It looks like SpaceX is not the only one setting unrealistic timelines?




  • I just compared the footage from various points in time. The flap positions for T+00:48:12 (pre-entry) and T+01:05:41 are almost the same, then it rotates about its rotation axis until T+01:05:44, but suddenly it starts to rotate about ANOTHER axis, and at T+01:05:47, its at a completely new angle. I think T+01:05:44 is the point where the flap finally breaks (after touchdown, but before splashdown).

    I think we have seen motion as fast as the one at T+01:04:22, but the subsequent bounce is surprisingly strong. I still think that the flap was still under some control at that point.

    I heard rumors on reddit that SpaceX deliberately removed a single tile on this flap for testing purposes, but I could not find any reliable confirmation for this. They deliberately removed tiles on the engine skirt, though.


  • I expect the flap on the opposite side of the ship experienced a similar level of destruction. Well, that depends on whether the damage occurred because of a general loss of structural integrity because of excessive heating, or if specific localized damage on that flap allowed plasma to penetrate the heat shield, resulting in the damage that we observed. So, general structural failure vs. random damage at that location cascading into a hole in the flap.

    Anyways, I am pretty sure that the complete loss of control authority on one of the flaps would be catastrophic. But the movement that we observed seemed pretty deliberate and consistent to what we saw during the suborbital test flights. Especially the unfolding of the flap at the T+01:05:42 mark is EXACTLY what we saw during the high-altitude flights, e.g., see SN8 @ T+6:33 or SN9 @ T+6:18. The forward flaps are folded back at first, and then rotate into a position perpendicular to the surface of Starship. The movement (for IFT-4) is precise, consistent with previous flights, and stops abruptly in the correct position.