Containing shuttle tank foam

[lbiderman]

<blockquote><font class="small">In reply to:</font><hr /><p> Is that mainly because of the Russian's automated docking system? Could the station's RMS handle the docking? It would dock the US module. <p><hr /></p></p></blockquote><br />No. Actually, it's because the module won't have enough space for dock. You would have to undock Node 3 to dock the russian module. Shape has a lot to do. With the Node 3 installed, there will be no room to manouver, and also the docking port won't be clear for the docking procedure, with or without RMS

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>Russia used their Proton rocket which can lift 20 tonnes, comparable to the shuttle. <p><hr /></p></p></blockquote><br /><br />Of course, one thing to consider is that a sizable chunk of the Proton's payload will be expended in propulsion for the module. With the Shuttle, much more of your payload can be stuff intended for use on orbit rather than stuff for getting it to the destination. Plus, Shuttle's launch environment is more benign and loads are distributed differently, so you can also save mass in the structure. Shuttle actually does have a lot of advantages, at least from the perspective of a payload designer. And that's why it's going to have to stick around until ISS is finished. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[mlorrey]

ah, double standard!<br /><br />By the standard you apply to the Proton, you must count the entire mass of the Shuttle and the fuel it carries as 'payload'. As the Shuttle weighs 235,000 lb, and with a 50,000 lb load weighs 285,000 lb, the STS 'payload' would be 130 metric tons, compared to the Protons 20 tons.<br /><br />(This coming from a shuttle critic: yes it is a flawed launcher, but it is a very big and capable flawed launcher)

 

[CalliArcale]

No, no. If you count the whole Shuttle, you have to count the whole Proton, and you want to just count its payload. <img src="/images/icons/wink.gif" /> That makes it an apples-to-oranges comparison, because they are fundamentally different launchers.<br /><br />My point is just that there are some very significant advantages, from an engineering perspective, to using the Shuttle for station assembly. This is not surprising; this is the job Shuttle was designed to do. This is also what makes it such a bad choice for almost every other application. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[willpittenger]

Sorry. When the Russians launch a module, your 20 tons has to include a stage on top of the Proton that delivers it to ISS. With the shuttle, that is including in the shuttle's own weight. The module can be simply lifted out of the cargo bay and attached. The module does not require its own modules. <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>

 

[mlorrey]

No, Calli. Not counting the fuel, the ET, or the SRB. Nor do we count the suborbital stages of Proton. We count the entire mass that winds up in orbit at ISS. In this case, Proton delivers 20 tons TOTAL, including the mass of the orbital insertion stage, as does Shuttle, delivering the Orbiter and its payload, 130 tons. The mass of the whole STS is over 2 million lbs.

 

[peter1024]

I would have thought that Plastic "Shrink Wrap Netting" could be used to "embrace and contain" the foam -- should be very Strong & Light.<br />- more effective if regular anchor points available.<br /><br />This is similar to your suggestion of "Plastic membrane", but a bit more specific.<br /><br />One of the ideas behind the netting, is that it's mostly empty space -- that makes it lighter. My guess would be that a hole size of about 2 inches (probabily hexagonal) would be best.<br /><br />Some concern though if the "Shrink Wrap" imposes too much inward pressure on the fuel tank. Would need to experiment to get best set of conditions.<br /><br />(The shrink wrap is heated with an air gun, causing it to shrink, after it's wrapped around the object. Controlling the air temperature of the hot air gun, controls the amount of shrinkage.)

 

[peter1024]

Actually, forget the shrink wrap, use an oriented fiber, polythene net.<br />That would be both stronger and lighter.<br />Then lace together with welded orientated poly cord.<br />(Oriented fiber polythere, is pre-stretched, by a factor of about 20, the orientates the molecular chains, and significantly increases strength (unidirectional).)<br /><br />That's the wrapper.<br /><br />As for the foam: I don't know what it's density is or it's thickness.<br />I would guess that it's about 4 inches thick ?<br /><br />Using the same orientated fiber material (cross-ply), as a 'structural backing'<br />I did wonder if a strong multilayered, 'micro-cell-bubble-wrap' material could be used. -- Again this would be very light, much stronger then normal bubble wrap. (by a factor of about 1000 - due to the orientated fiber backing).<br /><br />Also this wouldn't "fall apart". Relying here on the super strong backing (within each layer) for structural strenght, - so that it wouldn't "sag".<br /><br />What do you think ? -- An interesting idea ?<br /> <br />I was at one point going to try to email those ideas to NASA some time ago,<br />- but couldn't find 'a where' to submit the idea to.<br />- So I gave up in the end. -- But I think this could work.<br /><br />There again - at cryogenic temperatures, perhaps it would be too brittle for those areas right next to the tank.<br />NASA's solution, has the benefit of using a single layer, which has simplicity going for it - but has the structural stength problem.