Orion heat sheild and other capsules

[holmec]

I'm curious to know about the heat shield of Orion. I understand that the Apollo heat shield was an epoxy based substance with asbestos in it.<br /><br />Since asbestos is now illegal to use, due to its hazardous nature, what will NASA use for Orion's heat sheild.<br /><br />Also what is interesting to note is that t-space's capsule was going to use tiles like that on the STS, but a double layer.<br /><br />And anyone know what type of heat shield SpaceX will use on Dragon?<br /><br />And what do the russians use on Soyuz?<br /><br />And finally what else can we use, or what is on the horizon of new materials that can be used as heat sheilds? <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[vulture2]

Asbestos is not illegal to use, but because of liability problems it is seldom used. It is a hazardous material, but it can be used safely with proper precautions. I have not found a reference that says asbestos was used in the Apollo heatshield, however there is asbestos in the insulation that lines the SRB fuel segments.

 

[willpittenger]

From Wikipedia: <font color="yellow">The CM itself will be covered in the same nomex felt-like thermal protection blankets used on non-critical parts on the Shuttle (such as the payload bay doors) while the Thermal Protection System (TPS) will be made of a derivative of the Phenolic Impregnated Carbon Ablator (PICA) heat shield previously developed for the Stardust return mission.</font>/safety_wrapper> <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>

 

[jimfromnsf]

wiki is not a source

 

[lampblack]

<font color="yellow">You mean SRB propellant segments.</font><br /><br />Pet peeve? <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <font color="#0000ff"><strong>Just tell the truth and let the chips fall...</strong></font> </div>

 

[j05h]

<i>> wiki is not a source</i><br /><br />Actually, wikipedia is a surprisingly common source. Accurate? Sometimes. It can't be denied how popular the site is. In this community, astronautix.com gets slammed sometimes as well. Both sites contain errors. One because to many people maintain it, the other because of to few contributors. Both have their uses. WIki has one huge advantage over some other online sources. The site is open and linkable. I bang my head against the AIAA and NSF L2 every once in a while, and it is frustrating. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[Huntster]

I'm a major fan of Wikipedia, and a constant editor as well. However, jim is partially correct in that it should not be used as, or consider to be, a reliable source. Rather, use it as a jumping-off point. If a statement or fact contained in an article is not sourced, then don't believe it. However, if it has a reliable source, pay it heed.<br /><br />Specifically regarding the article in question here, I find it to be extremely well sourced, and that particular quotation is attributed to <i>Popular Mechanics</i>, which I've always considered at least fairly reliable. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> </div>

 

[willpittenger]

If you don't like what I quoted, please correct the article. Please also note that, at times, Wikipedia has been found to be more accurate than Encyclopedia Britannica. <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>

 

[qso1]

If you can provide some good source material, wiki could use your input and you can help make it a source. Personally, I use several sources including wiki. Utilizing several sources is the best way to get around the most common problems including the perception of a source not being a source. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[PistolPete]

What I normally do when I need to use some information off of Wikipedia is I try to find in the reference section where the author of the article got his information from and use that as my source. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[holmec]

Yeah you should consider the SOURCE. Wiki usually has back up sources links. <br /><br />Wiki is a source but may not be a good one. <br /><br />Funny that Jim never says "wiki is not a reliable source" but just says "wiki is not a source". Must be a fear of adjectives. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

Thanks. I'll check it out. <br /><br />Here is a NASA article in it. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[rocketwatcher2001]

Will-<br />Please keep up the good work. You can keep referencing wiki, astro, and everything else as far as I'm concerned. I enjoy reading your posts. If I think there is an error, or some other mistake, I hope to discuss it with you here as 2 gentlemen should. <img src="/images/icons/smile.gif" /> <br /><br />But so far, I think you're batting nearly a thousand. Please keep it up, and don't let some "expert" who thinks it's a good idea to put a large winged manned vehicle on top of a rocket get you down. <div class="Discussion_UserSignature"> </div>

 

[jimfromnsf]

"You can keep referencing wiki, astro, and "<br /><br />And he will be wrong. With WRT spaceflight, wiki is one of the worse sources. <br /><br />It is better to go to NASA.gov like holmec did for his link<br /><br />As for the assine remark, I never said "large". And Dynasoar, early shuttles and OSP were going to put winged vehicles on top of launch vehicle.<br /><br />But then again I am a "rocket worker" and not a just a "rocketwatcher"<br /><br />

 

[rocketwatcher2001]

<font color="yellow">"You can keep referencing wiki, astro, and " <br /><br />And he will be wrong. With WRT spaceflight, wiki is one of the worse sources. <br /><br />It is better to go to NASA.gov like holmec did for his link </font><br /><br />The wiki article sourced several NASA links. In Will's case, all of his info was correct, wasn't it?<br /><br /><font color="yellow">As for the assine remark, I never said "large". And Dynasoar, early shuttles and OSP were going to put winged vehicles on top of launch vehicle. </font><br /><br />You were specifically talking about Buran, saying that CP wasn't a consideration on where it was mounted on the launch stack. That's the dumbest thing I've read by a supposed "expert". Would you like me to quote you exactly?<br /><br /><i>"So why was the Soviet Shuttle Buran mounted aft and sideways instead of on top?" <br /><br />It made less impacts on ground faciliities. It was easier to switch from a cargo pod to an orbiter on the side and it wasn't as high. And it was like the US version. CP location wasn't a consideration </i><br /><br /><br /><font color="yellow">But then again I am a "rocket worker" and not a just a "rocketwatcher" </font><br /><br />You seem to enjoy mocking my user name, while you play your shuttle experiance as some kind of trump card, but it's not, all it says to me is that you are a one Hell of a legend in your own mind. I know far too many folks in the Shuttle program to think that you are some kind of "expert". Your space program experiance initially open up a door and gave you an instant stock value, but your posts have made that stock fall like a homesick brick.<br /> <div class="Discussion_UserSignature"> </div>

 

[jimfromnsf]

"Your space program experiance initially open up a door and gave you an instant stock value, but your posts have made that stock fall like a homesick brick. "<br /><br />Doesn't matter what you think, my posts were correct. CP wasn't the primary consideration and there was many other overriding requirements.<br /><br />Fortunately, I don't work in the shuttle program anymore. My time in the USAF, in which I received briefings on the Soviet space program and my current job in launch vehicle integration backs up my posts.

 

[rocketwatcher2001]

<font color="yellow">Doesn't matter what you think, my posts were correct. CP wasn't the primary consideration and there was many other overriding requirements.</font><br /><br />No, your posts are not correct. The Soviets studied several different configurations in wind tunnels and discovered for themselves that the Buran's configuration was the best for aerodynamic reasons.......CP. <div class="Discussion_UserSignature"> </div>

 

[willpittenger]

I think it is time someone backed up their claims with documentation. Otherwise, I might have to alert a moderator to the argument. <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>

 

[CalliArcale]

A moderator has already noticed.<br /><br />Okay, folks, time to cool things down a bit. Please, do not bring arguments into tangentially-related threads. This thread *was* about the heat shield on Orion. While Buran may be tangentially significant, it really does a disservice to the original post to make it the sole topic of discussion -- especially when the discussion is so heated. This apparently came from another thread; please consider returning to that thread rather than bringing the argument into this one.<br /><br />I also have to remind folks now that it is not acceptable to make cheap shots at other member's usernames. That's very thin ice indeed.<br /><br />Lastly, it is very poor manners to go after other member's credentials and sources without justification, especially when it is done in the total absence of any real contribution to the discussion. If your only contribution is to denigrate another member (whether you feel it is deserved or not), think very carefully about what you intend to acheive, because it doesn't advance the discussion at all, and puts people on the defensive. Go ahead and question people's background if it's relevant, but don't completely diss everything they have to say as if they're not good enough for you. Everybody has a right to an opinion, and an opinion isn't automatically better just because it came from someone with good credentials.<br /><br />That said, willpittenger is right. If you're going to get all high and mighty about your claim being the correct one, you ought to be prepared to put your money where you mouth is and show documentation. If you can't provide the documentation, then it's good manners to acknowledge that others have no reason to believe you. <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>

 

[jimfromnsf]

http://uplink.space.com/showthreaded.php?Cat=&Board=missions&Number=769849&page=3&view=collapsed&sb=5&o=21&vc=1<br />"If astronautix is to be believed, Soviet engineers toyed with various designs, some better than shuttle, but were ordered to make it as similar to shuttle as possible so no one could claim Soviet equipment is inferior to US" <br /><br />http://www.astronautix.com/craft/buran.htm<br /><br />"There was severe criticism of the decision to copy the space shuttle configuration. But earlier studies had considered numerous types of aircraft layouts, vertical takeoff designs, and ground- and sea- launched variants. The NPO Energia engineers could not find any configuration that was objectively better. This only validated the tremendous amount of work done in the US in refining the design. There was no point in picking a different inferior solution just because it was original."

 

[willpittenger]

Thanks Calli. I was thinking it would degenerate further. I guess I was still more patient than you. <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>

 

[willpittenger]

I don't know where I heard these as both were from at least 10 years ago. One was from when Buran was first shown to the world.<br /><li>Claim 1: Buran's chief designer admitted in public that they outright copied the Rockwell design.<li>Claim 2: Buran's design was proof that Rockwell's design was superior to other options.</li></li> <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>

 

[holmec]

"Asbestos is not illegal to use"<br /><br />Your right. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[windnwar]

From what info I could find the Apollo heat shield was a fiberglass hex grid with each hex filled with a silica impregnated epoxy. I couldn't find anything that said it used asbestos specifically, although contained in an epoxy asbestos would be very safe to handle prior to launch and fairly easy to take precautions to handle it after it lands. <div class="Discussion_UserSignature"> <p> </p><p><font size="2" color="#0000ff">""Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." --Albert Einstein"</font></p> </div>

 

[windnwar]

I found this in a Wired article from November 2006 that listed the entrants for the heat sheild material. <br /><br />PICA<br />Special feature: Rayon<br />PICA already survived one 29,000-mph return to Earth – on the bottom of the Stardust comet probe. The material is made by roasting rayon (yes, like in your shiny shirt) until it's just a loose carbon-fiber matrix, which is then infused with a phenolic resin (similar to what billiard balls are made of). Heat-treating the resulting goop hardens it into blocks that are cut to shape.<br /><br />3DQP <br />Special feature: Quartz fibers<br />Originally used to protect the apocalyptic payloads of intercontinental ballistic missiles, this heat shield (made by Massachusetts-based Textron Systems) consists of a malleable top layer of loose quartz-fiber cloth saturated with phenolic resin over a layer of insulating foam.<br /><br />ACC <br />Special feature: Extra density<br />Lockheed's entry, advanced carbon carbon, is the thinnest and densest of the lot – its outer layer is 0.5 inch thick and weighs in at more than 100 pounds per cubic foot. ACC, which protected NASA's Genesis capsule during a September 2004 crash landing, burns slowly, gets very hot, and requires up to 4 inches of calarb insulation (the stuff that lines your oven).<br /><br />Avcoat<br />Special feature: Honeycombs<br />Avcoat protected the Apollo capsule in 1969 – so long ago that Textron had to reinvent the formula. It's a glass honeycomb structure, filled with silica, phenolic resin, and "microballoons" to create a single-layer shield that simultaneously ablates (burns off) and insulates.<br /> <div class="Discussion_UserSignature"> <p> </p><p><font size="2" color="#0000ff">""Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." --Albert Einstein"</font></p> </div>