ISS Assembly and boost questions

[willpittenger]

* When an orbiter (or in the future, something like a CEV) boosts ISS, how do they keep the center of mass aligned with the center of thrust. I assume if the two are not aligned, the station would just spin. How much stress can the docking connector take? As the station's mass grows, wouldn't that be an issue? Was the shuttle system designed with boosting large stations in mind?<br /><br />* Will the station crews be able to move the solar arrays without an orbiter present?<br /><br />* Why have all Quest spacewalks (that I know of) happened only when an orbiter is present. Futhermore, it is not station crew doing the spacewalk. When a spacewalk happens without an orbiter, I always hear they used the Russian suits. Why are the Russian suits and Pier module even needed? Can't the Quest module (which is far roomier) and US suits do the job?<br /><br />* Please compare the images for STS-115 and STS-116 on the page http://spaceflightnow.com/shuttle/sts115/fdf/manifest.html. You will find that a solar array vanished. Where will it go?<br /><br />* Will uneven distribution of mass cause stability problems? <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[erioladastra]

"Will the station crews be able to move the solar arrays without an orbiter present?" <br /><br />'Yes, the ISS arm can move the arrays along the ISS truss. '<br /><br />To calrify a little. The P4, S4 and S6 solar arrays will be taken up on the shuttle, the SRMS will unbert them, handthem to the SSRMS which will then mate them in place while the shuttle is there. P6, on 10A, will be taken off of Z1 and mounted on the mobile transporter (MT) on the Payload ORU Accommodation (POA) fixture. The MT will then go along the truss to the end of the prot truss. There the SSRMS will regrapple it and attach to the end of the truss. The orbiter will be docked the entire time.<br /><br />"They have not been only out of Quest AL with the Orbiter present."<br /><br />AS Shuttle_guy points out they have not all be when the orbiter was present. However, there was an equipment problem and it was out of commission for a while and the lack of shuttle missions delayed the repair. But it is now fully functional and do it size and outfitting, is the prime A/L for all USOS EVAs. The RS A/L will only be used for RS EVAs. Besides backup it also makes sense. You lose a lot of time translating along ISS so always going out the US A/L to work on the SM aft would waste a lot of time, while the RS A/L is much closer.

 

[spacester]

Now I'm just asking a question here, no criticism of anybody is intended. OK?<br /><br />Has the MT ever actually been tested under load, or even unloaded? As I recall, it was inoperable until recently when the severed cable thing was corrected, and I don't recall it being in the news since.<br /><br />Surely (is anyone here is named Shirley? <img src="/images/icons/tongue.gif" /> ) they plan to test it before showing up with a big ol' solar array to move around?<br /><br />[It certainly is nice to be asking questions about ISS assembly again. Kudos again to NASA on STS-121 and STS-115 prep to date. Especially the folks at Michoud, I don't think they've gotten enough credit.] <div class="Discussion_UserSignature"> </div>

 

[erioladastra]

"Has the MT ever actually been tested under load, or even unloaded? As I recall, it was inoperable until recently when the severed cable thing was corrected, and I don't recall it being in the news since. "<br /><br />Yes. It was workign for a long time before the TUS cable was severed. And it was working then too - that was a redundant line. However, you need to have the redundancy when you have things like P6 on it so the recent EVAs repaired the line. The POA camera was also fixed.