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Endeavour docks with ISS

Endeavour tonight has successfully docked with ISS.

When the spacecraft got within about 70 feet of the station, there was a delay of a little more than an hour while ground controllers installed a software overide to a sensor for monitoring the position of one of the 12 hooks on Endeavour, used to lock it to ISS’s docking port. Though visual and other data showed the hook was working, the sensor could not, and without that software override Endeavour would automatically abort the docking.

This same sensor had caused a delay in the opening of the capsule’s nosecone yesterday shortly after launch.

As of posting the hatch had not yet been opened, something that should occur in about an hour or so. Though Endeavour is docked, more checks needed to be done beforehand.

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  • Ray Van Dune

    As I understand it the latching mechanism consists of 12 pins, in two sets of six. The pins are driven into sockets, where they then rotate to engage a lock, and are then withdrawn to pull the ship and the ISS together. This happens twice, once for each set. I am not sure if the driving, rotating, and pulling is done by the ISS or the ship.

    I have a hunch this is not a SpaceX design – doesn’t sound like the work of the guy who said “The best part is no part” does it?

  • Ray Van Dune: Years ago the space agencies of the world decided it would be wise to make their docking ports compatible, so that in an emergency the spacecraft from one nation could dock with another. Therefore this docking design is almost certainly simply following in that path, and was not redesigned by SpaceX in any significant way.

  • Star Bird

    Skylab came to a firey spectacular end

  • Ray Van Dune

    Yes, a standardized docking design was and is required. My point is that it is quite complex, at least compared to what might be done today.

    Fundamentally, a design is driven by the requirements, and if the requirements are stringent enough, the design may well be driven to a high level of complexity. So as we move out of LEO, we may want to challenge our requirements. SpaceX would probably be an excellent leader to such a project. OTOH, the time may have already passed for it to be feasible.

  • Edward

    Ray Van Dune,
    The following video by Jared Owen may interest you. Mr. Owen has put together several videos describing how various spacecraft and rockets work, and he seems to have done his homework. This one is about the Dragon. Rendezvous with the ISS starts around 15 minutes, docking at 16 minutes, and the part about the latching hooks starts at the 18:29 mark.

    “How does the Crew Dragon Spacecraft work?” (20 minutes)

  • Ray Van Dune

    Edward, thanks very much. I will look it over this weekend sometime. I hope nobody thinks I am claiming I could design it better!

    Since you may know of a source, I have wondered for years exactly how rockets like the F9 use aerodynamic forces to manage their launch trajectories to best advantage. I am pretty up to speed on aerodynamics, but on aircraft, not as applied to rockets.

    Ps. On the next F9 launch, watch the deflection of the rocket plume as it is first increased upward to halt the initial gravity turn toward the launch heading, and then reduced to zero just prior to Max-Q to minimize lateral forces (I assume).

  • “Endearvour” – love the typo. No! Don’t fix it! Too late… Arrgghhh!

  • Michael McNeil: It might look cute, but I don’t go for cute, I go for accurate and thoughtful. :) Fixed and thank you.

  • Doubting Thomas

    I usually watch the streamed YouTube NASA or SpaceX feed showing the Crew Dragon docking and then the hatch opening / arrival ceremony on the ISS between the new and soon departing ISS crews.

    For Crew 6 Endeavor mission I saw the approach and docking streamed on both channels, along with the discussion about the latching issue for Dragon. But I see no streamed feed on the hatch opening / arrival ceremony. I wonder if NASA just stopped doing this?

    Robert or anybody else know?


  • Doubting Thomas: I almost never watch the docking procedures but did so this time (on the youtube feed). According to the announcers they were going to cover the hatch opening, but then apparently ended early. I suspect it was still covered on NASA’s main feed. I just didn’t bother with it, as it isn’t that interesting.

  • Doubting Thomas

    Ok, Thanks Robert. I usually just zip through it to see the two crews greet each other, still thrills me to see people moving around in a larger volume in zero-g (or now called “microgravity). Like to compare it to the old images in my head of Matt Dodson floating through PRS Aes Triplex or the Stone family living aboard The Rolling Stone in the Heinlein juveniles.

    Still don’t see it posted on NASA or SpaceX YouTube channels. Guess they just broadcast on NASA TV (which I don’t get) and didn’t bother to capture it for YouTube channels.

    Thanks again.

  • Doubting Thomas: NASA probably broadcast the hatch opening on NASA TV live, but it might not be archived anywhere.

    FYI, NASA TV is available on the web for anyone. The youtube channel:

    Or on NASA’s website:

    I have technical issues with NASA’s website, but the youtube channel works, when needed.

  • Edward

    Ray Van Dune,
    I don’t know of any sources, but my understanding is that without fins at the bottom end, rockets do not use any aerodynamics to control or manage their flight trajectories. Instead, they use such things as vectoring their engines from commands by their guidance controllers. This kind of control is what they are depending upon for Starship, with the fins that are located at the upper end of the rocket stack rather than fins located on the lower end — it is like trying to shoot an arrow backward, feather-end forward.

    You mentioned the pitch over, or gravity turn. I’m not sure that there is much in the way of aerodynamics in that maneuver, because cylinders are not so aerodynamic. It is possible that SpaceX is counting on some amount of aerodynamics to keep Starship high enough in the atmosphere during reentry that they need not have ablative heat shielding.

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