When looking at Crew Dragon flight paths diagrams I saw that for phasing burns and deorbit burns they don't use the side thrusters, as I would expect, but four thrusters mounted at the "top" of the capsule. (The iconic side pods are used only for abort launch aborts)

During these maneuvers the astronauts should feel like the cabin is upside-down. Right?

How does the crew deal with it? I haven't seen any image of when that happens. Do they strap themselves to the chairs and "hang" over the control screens? That doesn't look like a good position to pilot. Or do they squat on the "ceiling" in front of the control screens like they would in front of a low table?

By the way, how many G do they feel during these maneuvers?

According to CNN and other sources the deorbit burn is 11.5 minutes and the speed in orbit is 17'500 mph, or 7'823 m/s. If the capsule had to loose all of that speed in 11 minutes that would be a deceleration of 11.3 m/s^2. A bit over 1G. But since most of the speed is actually lost during reentry, by friction, the actual g-force during deorbit should be a fraction of 1G.

For the soyuz capsule the breaking maneuver takes 5 minutes and the g-load is only 0.05 G.

  • 1
    $\begingroup$ I believe it's a tiny fraction of 1G and not for terribly long. $\endgroup$ Commented Sep 19, 2020 at 20:42
  • $\begingroup$ I added that calculation. That seems correct. $\endgroup$
    – Florian F
    Commented Sep 20, 2020 at 1:44
  • $\begingroup$ @FlorianF the deorbit burn just lowers the perigee into the sensible atmosphere. For shuttle it was only ~100 m/s space.stackexchange.com/q/12011/6944 $\endgroup$ Commented Sep 20, 2020 at 2:01
  • $\begingroup$ Thanks for the link. Indeed, the acceleration felt by the astronauts is pretty low. This answers the question of how they handle it: it is not much of a problem. $\endgroup$
    – Florian F
    Commented Sep 20, 2020 at 2:40
  • $\begingroup$ more with same result: How hard do you have to throw something off the ISS to make it deorbit? $\endgroup$
    – uhoh
    Commented Sep 20, 2020 at 3:29


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