New Ares I trade study....

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docm

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http://www.nasaspaceflight.com/content/?cid=5279<br /><br />1. SRB not reusable<br /><br />2. totally new nozzle<br /><br />3. possibility of HTPB fuel grain for Ares V<br /><br />and God knows what else.<br /><br />Seems like they're in the process of hosing the taxpayer even more than they already have. At what point do they grow a brain and go for an ELV?<br /><br />One of the responders at NSF commented that NASA was close to jumping the shark. I agree. <div class="Discussion_UserSignature"> </div>
 
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hal9891

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<blockquote><font class="small">In reply to:</font><hr /><p> At what point do they grow a brain and go for an ELV? <p><hr /></p></p></blockquote><br /><br />Or even better for DIRECT.<br />That proposal just makes so much more sense than Ares I/V that I wonder why they are being considered in the first place. <div class="Discussion_UserSignature"> <div style="text-align:center"><font style="color:#808080" color="#999999"><font size="1">"I predict that within 100 years computers will be twice as powerful, 10000 times larger, and so expensive that only the five richest kings of Europe will own them"</font></font><br /></div> </div>
 
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docm

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From the above interview;<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>NASA) Our analysis has shown the current Ares I and V architecture to be the lowest life cycle cost solution combined with the highest crew safety/reliability that meets our architectural requirements. NASA has assessed 'Direct' type options in the past. They fall short of performance requirements needed for lunar missions, have lower crew safety/reliability projections and higher up-front costs. <p><hr /></p></p></blockquote><br /><br />Higher up-front costs than the Ares I fiasco? <br /><br />ROFLMAO! <div class="Discussion_UserSignature"> </div>
 
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vulture2

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>>1. SRB not reusable <br /><br />Reuse of the current SRBs is not economically viable, since they must be completely rebuilt between missions. The decision to recover them was made before any data on the cost of doing so was available. It may well be possible to design a booster that could be economically recovered, but the booster proposed for the Ares is clearly not such a design, so unfortunately there is no logical reason to recover it. <br /><br />The fundamental error NASA is making is using the concept of "life cycle cost". If the "mission" is just to perform a few moon landings and then quit forever, then using the "life cycle cost" makes sense. But if our objective is to make human spaceflight practical, than we need reusable technology. Choosing an obsolete design because it minimizes the cost of the next ten flights is completely inappropriate; after those flights we will be no better off than we are now.
 
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hal9891

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ROFLMAO indeed.<br />2x Jupiter-232 could deliver much more cargo to moon than Ares I+V could ever dream of, not to mention how much would be saved by not upgrading SRBs to 5 segment version or developing and launching only one booster instead of two.<br />Lower crew safety? With all the ongoing castration of Orion just to fit it on Ares-I it's doubtfull it will be any safer and with higher Jupiter performance it could be made much safer and heavier if needed, they could even bring back the 5.5m capsule if they wanted so.<br /><br />Instead of "Shuttle Derived" and "Apollo On Steroids" it's seems more and more like "Shuttle Inspired" and "Apollo On Vitamins" <div class="Discussion_UserSignature"> <div style="text-align:center"><font style="color:#808080" color="#999999"><font size="1">"I predict that within 100 years computers will be twice as powerful, 10000 times larger, and so expensive that only the five richest kings of Europe will own them"</font></font><br /></div> </div>
 
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missile_mother

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I believe reusability is as not important as recoverability and hardware with proven heritage. This is why the SRB is suppose to be safer. Cost has little to do with it
 
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propforce

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Hey Missile_Mother, I have not come across that term for 10+ years! It's good to know that some still use them <img src="/images/icons/smile.gif" /><br /><br />Here's a related story from Flightglobal.com<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><br /><b>NASA admits 'significant threats to performance' of Ares I launcher </b><br />By Rob Coppinger<br /><br />NASA has admitted in an internal circular that there are "significant threats" to the performance of its Ares I crew launch vehicle (CLV), as Flight has learned that <b>the preliminary design review for the CLV first stage has slipped by up to six months.</b><br /><br />The Ares I first stage is based on the Space Shuttle's four-segment reusable solid rocket motor (RSRM), but with five segments. <font color="yellow">Initially intended to be largely unchanged from the RSRM, its insulation, throat diameter, propellant chemistry and geometry, and number of segments had all been changed by December 2006.</font>NASA sources also say that, due to ascent stresses, areas of the segment casing are to be modified for strengthening.<br /><br />The first stage is being designed to lift the CLV's upper stage, the Orion crew exploration vehicle (CEV) and its launch abort system to 129.5km (80.4 miles) before staging. The first manned flight is planned by March 2015.<br /><br />The Ares I programme has been dogged by rumours of inadequate performance and blamed for repeated redesigns of the Orion's crew and service modules driven by the need to reduce mass. NASA has refuted the rumours and maintained that the Ares I CLV is capable of meeting requirements.<br /><br />But now the agency's November internal circular says: "There are significant threats to the performance to be worked as the project works towards [PDR]."<br />:<br />:<br />:<br />:<p><hr /></p></p></blockquote> <div class="Discussion_UserSignature"> </div>
 
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holmec

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<blockquote><font class="small">In reply to:</font><hr /><p>Or even better for DIRECT. <p><hr /></p></p></blockquote><br /><br />Yeah, or a total redesign of the first stage. <br /><br />In any case, this is bad news.<br /><br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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holmec

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<blockquote><font class="small">In reply to:</font><hr /><p>Instead of "Shuttle Derived" and "Apollo On Steroids" it's seems more and more like "Shuttle Inspired" and "Apollo On Vitamins"<p><hr /></p></p></blockquote><br /><br />I agree with "Shuttle Inspired", and I'm fine with that. "Apollo On Vitamins", well that's a problem. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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mattblack

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"Jumping The Shark": that would be me... But then they went and deleted my post and references <img src="/images/icons/rolleyes.gif" /> <div class="Discussion_UserSignature"> <p> </p><p>One Percent of Federal Funding For Space: America <strong><em><u>CAN</u></em></strong> Afford it!!  LEO is a <strong><em>Prison</em></strong> -- It's time for a <em><strong>JAILBREAK</strong></em>!!</p> </div>
 
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docm

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IMO Chris does get a little heavy-handed at times. <div class="Discussion_UserSignature"> </div>
 
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holmec

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Actually this interview is pretty insightful.<br /><br />IMHO what it says:<br /><br />1. Direct is dead.<br /><blockquote><font class="small">In reply to:</font><hr /><p>NASA has assessed 'Direct' type options in the past. They fall short of performance requirements needed for lunar missions, have lower crew safety/reliability projections and higher up-front costs. <p><hr /></p></p></blockquote><br />Looks like it would take an act of Congress and some heafty documentation to change that.<br /><br />2. <font color="red">Red Flag</font> Answer excerpt to question 8.<br /><blockquote><font class="small">In reply to:</font><hr /><p>We do track and manage risks - currently, our top risks center around completing the integrated requirements allocation and our ability of heritage hardware to meet Ares requirements. <p><hr /></p></p></blockquote><br /><br />This is a little insight full tidbit. This tells me that the first stage will change. They are meshing the SRB hardware with Ares requirements, and who knows what will come out the other end. It seem probably that the Ares I first stage will be different to that of the Ares V SRBs and the Shuttle's SRBs. So you end up with customized parts. This could mean more building space and hardware for the assembly plant. Thus more expense. <br /><br />Quite frankly I wouldn't be surprised if the first stage of Ares I ends up with fins.<br /><br /><br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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radarredux

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> <i><font color="yellow">Seems like they're in the process of hosing the taxpayer even more than they already have. At what point do they grow a brain and go for an ELV?</font>/i><br /><br />I am getting Ares I fatigue, and by extension Constellation fatigue.<br /><br />All engineering efforts have their challenges, but the Constellation architecture was largely chosen to reduce program risks. So far it just seems to be a frustrating exercise in continuous redesign and downsizing.</i>
 
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mattblack

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It wasn't Chris, but don't worry about it. <div class="Discussion_UserSignature"> <p> </p><p>One Percent of Federal Funding For Space: America <strong><em><u>CAN</u></em></strong> Afford it!!  LEO is a <strong><em>Prison</em></strong> -- It's time for a <em><strong>JAILBREAK</strong></em>!!</p> </div>
 
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frodo1008

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I must admit to originally supporting NASA on the Ares I design, as I thought that using the already developed shuttle propulsion system would indeed save funding for other parts of the program.<br /><br />However, when I read that ATK wanted some $3 billion just to develop a new five segment SRB I was truly shocked and disappointed. After all, the total cost of the EELV program to develop the entire launch system was only some $2 billion for both the Air Force and the private contractors!<br /><br />The situation seems to just be getting worse and worse. Then we find the head of the program has intimate connections with ATK, and then he is retiring! I know that NASA does have to play some politics (being a government agency), but at the highly increased costs that this program seems to be getting into?<br /><br />Then they come up with the supposed importance of man-rating systems to keep from even considering the use of the EELV's. Were the Redstone. original Atlas, Titan, and the fantastic Saturn launch systems man-rated?<br /><br />To someone like myself that was actually associated with the early programs the answer is a big no. How could there be, as these rockets were being used for the very first time with manned launches!<br /><br />So what is to stop NASA from using the already proven EELV's, besides politics that is? <br /><br />Besides developing a new five segment SRB should also mean that the Ares I itself needs to be man-rated also, if such man-rating is really that important at all that is!<br /><br />Besides this, I notice that there is no other space program in the world that proposes using such large SRB's. Do they possibly know something that NASA does not know?<br /><br /><br /><br /><br />
 
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baktothemoon

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This is looking more and more like a death spiral every day. I have this sinking feeling that we're going to be cut down to the bone again just like the shuttle and ISS.
 
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webtaz99

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I try to think of it as fuel for the fire of private space development. I feel that NASA should make payloads and spacecraft, not launchers. <div class="Discussion_UserSignature"> </div>
 
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usn_skwerl

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i came across this tonight...<br />http://www.gaetanomarano.it/articles/011srb5.html<br /><blockquote><font class="small">In reply to:</font><hr /><p> Why the 5-segments SRB can't work <br /><br />The new 5-segments SRB will be the main engine(s) of (both) the Ares-I and Ares-V giving all (in the first) or great part (in the latter) of the thrust to lift their 25 mT and 130 mT payloads.<br /><br />The 5-segments SRB is made to add "something more" to the booster: MORE THRUST (to lift more tons) or MORE BURNING TIME (to give more acceleration in the first part of the flight) or BOTH.<br /><br />Unfortunately, the 5-segments SRB can't give more burning time NOR more thrust, as I explain here (of course, this is only my opinion, but I think it's correct).<br /><br />The SRB looks like a "firecracker" but don't work in the same way; in a firecracker, the "propellent" burns from its top to the end, so, if we double its LENGHT, also the burning time doubles.<br /><br />But the solid boosters have an "hole" in the solid propellent with a "shape" that, in the standard SRB, is an 11-point star, so, the propellent don't burns from the bottom to the top of the booster but from the center of the booster to the internal part of the booster's rings.<br /><br />Then, if we add 1+ segments to the standard SRB without change its DIAMETER, the "burning time" remains THE SAME (about 2 minutes) and it CAN'T GIVE more acceleration to the rocket.<br /><br />Also, the 5-segments SRB can't give more thrust with the same nozzle, since, MORE thrust needs a LARGER nozzle, like ALL rocket engines, or (probably) due to the higher internal pressure, the real thrust may increase about 10%, but NOT the 25% they may expect with a 25% extra-propellent.<br /><br />The 5th segment don't adds "something GOOD" (more thrust and/or more burning time) but only "something BAD": more INTERNAL PRESSURE (due to 25% more propellent in the same volume</p></blockquote> <div class="Discussion_UserSignature"> </div>
 
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no_way

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please dont post links to and stuff from well known spammers. this belongs more in phenomena or free space.
 
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usn_skwerl

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I didnt know that, sorry. <div class="Discussion_UserSignature"> </div>
 
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josh_simonson

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He's been kicked out of most of the forums for general obnoxiousness. His grasp of physics is also very weak (or trollishly fraudulent).
 
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mattblack

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I joined some other sites besides this one: only to find him there, so I left and never came back -- his heart is sort of in the right place -- but he makes a lot of noise and I and others used to clash with him a lot. <div class="Discussion_UserSignature"> <p> </p><p>One Percent of Federal Funding For Space: America <strong><em><u>CAN</u></em></strong> Afford it!!  LEO is a <strong><em>Prison</em></strong> -- It's time for a <em><strong>JAILBREAK</strong></em>!!</p> </div>
 
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