NASA responds to Ares I thrust-oscillation issue

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frodo1008

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By the way, if you are indeed so knowledgeable about the solid rocket motors of the shuttle, just what IS the cost of a single such four segment motor (and by simple math the five segment would then be about 25% greater).<br /><br />I have seen on another thread that these motors are supposedly about $40 million each. If this is the case, (no pun intended), then a five segment motor would cost about $50 million each.<br /><br />Now, according to wikpedia (and some of my own sources) a new RS68 costs in at $14 million each. This makes a Delta IV with three such engines costs at $42 million at this time. However, the Delta IV has been pointed out to launch four more metric tons than the projected five segment Ares I. <br /><br />And the projected total launch costs for spacex are even far less than the Delta IV!
 
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j05h

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<i>>> "...RS68 is the only new liquid US rocket engine developed since the SSME"<br /><br /> />And the Merlin. Note that the Falcon rocket bodies also use friction-stir welding.</i><br /><br />I meant to be witty there. SHould read like "...the RS68 is the only new liquid US rocket engine to make orbit since the SSME."<br /><br />Falcon uses advanced materials and processing as well, yes. Atlas recently fielded a composite payload fairing, too.<br /><br />Josh<br /><br /> <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>
 
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radarredux

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> <i><font color="yellow">Isn't the short answer to that that Ares V is unaffected?</font>/i><br /><br />Ares V will use the same 5 segment booster that is the first stage of Ares I. If you abandon solving some of these problems now for Ares I, you just kick the problems down stream to Ares V.</i>
 
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j05h

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<i>> If you throw the development cost out of the window for a minute and just consider the production and operation costs. </i><br /><br />Yup, you're new around here. Production and operation costs for the Shuttle SRBs are roughly as high as liquids, there is no magical savings because it doesn't have a turbopump. <br /><br />You can't just sweep $6-15G under the rug and say it doesn't count because it's development money. That is 100s of tons into LEO at current launch costs, down the drain to replicate capabilities using inferior tech.<br /><br /><i>> There far fewer things inside to go wrong. Why do you think they went with them for the shuttle extra booster instead of a liquid booster? </i><br /><br />When things go wrong on a solid, they go REALLY wrong, real quick. NASA went with SRBs on Shuttle because they couldn't afford to develop the liquid flyback boosters orginally called for. Like Frodo says above, Shuttle and Ares (if they fly) will be the only crew launchers in the world using solids. <br /><br /><i>> The cost of a Delta will never go down even if we triple production... .Only a solid booster has that potential. </i><br /><br />Simple economics says that tripling production will bring down price, because cost-per-unit declines as production increases. You wants high labor costs? Solids, especially ATK's segmented units, are notoriously finicky to handle and require a lot of precision assembly. You also don't seem to realize that the SRBs are shipped in pieces from Utah to KSC. The entire Shuttle infrastructure is geared towards predictable budgets, not cost effectiveness. There is no way to turn these machines into "cheap" launchers - that can only occur with greatly increased flight frequency or airplane-like reusables.<br /><br /><i>> ...helicopter ...The finest piston engine could never match the reliability of a turbo fan jet. ...The RS68 and Merlin may be the newest engines but if I had to bet my retirement fund on which would light up on time i</i> <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>
 
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lampblack

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<font color="yellow">And there are two relatively simple and inexpensive methods of increasing this to a Delta IV Super Heavy.</font><br /><br />Yet another possibility comes to mind: While designing the Ares V vehicle, why not do some extra engineering work and also develop a corollary liquid-fueled rocket consisting essentially of the Ares V minus the solid rocket boosters?<br /><br />With five RS-68 engines, there should be plenty of ooomph to accomplish whatever it is that NASA is seeking to accomplish with Ares I. They'd still have the option of strapping on the SRBs for heavy cargo duties.<br /><br />What would be the downside of doing this? I mean -- besides the political objections that go with not keeping ATK busy enough? <div class="Discussion_UserSignature"> <font color="#0000ff"><strong>Just tell the truth and let the chips fall...</strong></font> </div>
 
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samkent

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I don’t know where you get a price of $42 million for a Delta launch.<br /><br />http://www.astronautix.com/lvs/delheavy.htm<br /><br />This link states that the price in 2004 dollars is $254 million for a Delta 4 Heavy. I doubt if the price has gone down in 4 years. And that doesn’t include the infrastructure at the cape needed to fuel and defuel the thing.<br />That’s a far cry from your estimate of $50 million for an Ares. The lifting ability is roughly the same. I’ll concede that the weights may have changed to the detriment of Ares in the past year. But the point is to get humans into orbit at the lowest cost with the fewest delays.<br /><br />http://en.wikipedia.org/wiki/Delta_IV_rocket<br />http://en.wikipedia.org/wiki/Ares_I<br /><br />Plus we will still have the same last minute delays due to this sensor or that valve.<br />Just because we are the only country attempting to use solids for human launches doesn’t mean it’s a bad idea. In 1945 we had some of the finest piston powered aircraft in the world. Should we have ignored the simplicity of the jet? I think you are assuming that since it has the same basic design as what the Chinese used centuries ago, it’s old technology. That is just not the case. It’s a new way of using what we have used before.<br /><br />It’s the same old mindset!<br /><br />Thomas don’t blow out your lamp, you’re going to need it.<br /><br />Alexander who are you going to call?<br /><br />Orville It will never fly. <br /><br />Henry That’s no way to build cars. The parts don’t fit perfectly.<br /><br />Bill No one wants Windows. Dos is more stabile.<br />
 
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docm

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On a different tack;<br /><br />Read an interesting post at NSF regarding the personnel revolving door at Constellation;<br /><br />Link....<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><blockquote><font class="small">In reply to:</font><hr /><p>daver - 22/1/2008 12:47 PM<br /><br />So Scott Horowitz bails and Skip Hatfield had to go into Griffen's office and say, "What's shaking?" <-purely speculation on my part.<p><hr /></p></p></blockquote><br /><br />kraisee - 22/1/2008 12:14 PM <br /><br />No, Hatfield was told to make Orion weight 'x' so it could fly on Ares-I. He told Griffin that was going to be impossible because they had already spent two years trimming as much weight off the thing and Griffin's new target wasn't achievable on the budget and schedule the Orion project had. He lost his job there and then.<br /><br />Hatfield's mistake was he challenged the great and powerful wizard behind the curtain.<br /><br />Ross.<p><hr /></p></p></blockquote><br /><br />Sad commentary..... <div class="Discussion_UserSignature"> </div>
 
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j05h

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<i>>> And there are two relatively simple and inexpensive methods of increasing this to a Delta IV Super Heavy.<br /> /> Yet another possibility comes to mind: While designing the Ares V vehicle, why not do some extra engineering work and also develop a corollary liquid-fueled rocket consisting essentially of the Ares V minus the solid rocket boosters?<br />With five RS-68 engines...</i><br /><br />Boeing claims to have growth options for Delta well over 100t, using RS68 and current D-IV tooling. Ares V is quickly becoming "Delta X" - it switched engines already. An intermediate option beyond the 7-core Delta IV proposal would be an Ares V core-stage with 6 or 8 Delta IV CBCs around it and another D-IV as the upper stage. Or it could go the Phil Bono route and be a large core with droptanks on the sides. <br /><br /><i>> What would be the downside of doing this? I mean -- besides the political objections that go with not keeping ATK busy enough?</i><br /><br />ATK opposition is the only downside. Maybe a few bruised egos at NASA. ATK should continue making missiles, which it is good at and get out of human spaceflight until it has a decent product. Economic fact is that Ares I is replicating capability, and doing it poorly. If NASA wants to really tackle Heavy Lift, they should focus on that and buy rides to LEO in the meantime. THey should ask themselves, what can we do with currently flying rockets like EELV?<br /><br />Just look at the Criticism section of the Ares_I page on wikipedia. The writing is on the wall. Even Frodo agrees.<br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>
 
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ruff_house

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ATK will have plenty of business once the Ares V gets rolling.<br /><br />Id beoing says wht have growth options for Delta of somethign comparable to Ares V, then its a shame we havent called Beoing for that as well.<br /><br />However, I like the Ares V. IT's big, and big is good. it's what we need.<br /><br />It's Ares I that makes me mad, because we are pouring billions from our budget into reinventing the wheel, or more accuritely, "reinventing the medium lift booster". and on top of that, we're doing it poorly, havign to constantly shrink our payload because it seems that for NASA the launcher whose sole purpose is to launch the Orion system, is more important than Orion itself. If we mooved to a modified EELV, we could do it cheaper, we could do it faster, and now it seems we could do it safer.<br /><br />If NASA has a good Engineering reason for this pathway, I am behind them 100%, but if it is as it seems, that this is all Ego and croneyism, Then they have explaining to do.
 
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j05h

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<i>>That’s a far cry from your estimate of $50 million for an Ares. </i><br /><br />There is no way that Ares I would fly at only $50m/flight. Even forgetting development costs. <br /><br />Do you see how Ares I "costs" NASA while existing, commercial rockets only have a "price"? This is a critical difference, one option will always be certain amount of money, the other is ordered as needed. There-in lies the rub of the problem. Do you understand that they are replicating capability while being the only customer of Ares I? Do you understand that Ares I & V will not be for sale?<br /><br /><i>>Plus we will still have the same last minute delays due to this sensor or that valve.<br />Just because we are the only country attempting to use solids for human launches doesn’t mean it’s a bad idea. In 1945 we had some of the finest piston powered aircraft in the world. Should we have ignored the simplicity of the jet?</i><br /><br />Stop obsessing on the valves. All rockets experience launch delays - equipment, weather, paperwork, etc. <br /><br />The jet engine is not simple, neither are the SRBs. The SRB uses massive hydraulics, run by a TURBOPUMP (oh no), that provides Thrust Vector Control during flight. Solid rockets are not the panacea you claim, nor are they cheap and simple. <br /><br />You want simple, high-tech, elegant spacelaunch? The answer is laser-launch or maglev-to-laser launch. The technology is almost there, the basic system designed by Myrabo works. Properly designed, it doesn't even need moving parts. <br /><br /><i>>Henry That’s no way to build cars. The parts don’t fit perfectly. </i><br /><br />The US has the assembly line, it's the Delta IV plant, it sits largely idle. In existing rockets (mostly EELV, Soyuz, Ariane), we have the capacity to spread into the Solar System. There are not enough payloads to take the next step up in production, ie flight frequency, which is the only thing that will lower launch costs.<br /><br />Last point, since you <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>
 
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no_way

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<blockquote><font class="small">In reply to:</font><hr /><p>THey should ask themselves, what can we do with currently flying rockets like EELV?<p><hr /></p></p></blockquote><br />Gemini program had a path mapped out to lunar landing using Saturn IB and Titan 3Cs, thats way smaller than upper range of current EELV payloads.<br />So if you ask this question from the right people, they would answer "with rockets like EELV we can get to moon sooner than Apollo did" because that was the alternative plan.
 
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frodo1008

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You really are a newbie here, aren't you! <br /><br />I was talking about the PROPULSION system, not an entire launch vehicle! The Ares I is going to consist of FAR more cost than just the Large Solid Rocket Boosters, just as the Delta IV consists of FAR more than just the RS68 engines!<br /><br />I thought that was clear from the fact that we were NOT comparing the total launch costs, but only the relative engine and motor costs!<br /><br />By the way, even with a relatively low flight rate at this time a Delta IV Heavy Launch is far less than even half of a shuttle flight launch cost, and if you were to project the Ares I flight cost from the current number of projected flights and the total Ares I cost you would find that a Delta IV current launch cost (which, once again beats out the Ares I by about 4 mt to LEO) is going to be far less than half the cost of an Ares I launch!<br /><br />Plus the Delta IV is going to have far more launches anyway, which will bring the over all cost of a Delta IV launch down even lower!<br /><br />Do at least try to pay attention here!
 
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docm

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Isn't that a few years overdue? <br /><br />As soon as "the stick" was seriously considered such readings should have been done <b><i>before</i></b> committing billions of dollars to it. Define all your parameters before they define you.<br /><br />IMO more bass-ackwards engineering <img src="/images/icons/mad.gif" /><br /><br />In a few months an "abandoned" NASA vehicle will fly on an EELV, and IMO it won't be the last. Meanwhile they're stuck trying to stop this turkey from drowning itself in the rain. <div class="Discussion_UserSignature"> </div>
 
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windnwar

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This list of possible fixes looks like such a bandaid approach to the problem. Not to mention as soon as they start having to change the geometry inside the casings up goes the development costs again, not to mention more test burns of the segments, and possible loss of more performance. <br /><br />This is definately bass-ackwards. <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>
 
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halman

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JO5H,<br /><br />I am not certain, but I believe that ATK is a major military contractor, which is having trouble surviving on military contracts. The military-industrial complex is up against the wall, because the technology that they are working with is so expensive to develop that recouping costs from strictly military purchasing is impossible. In my opinion, the space program has, from the start, been welfare work for the military-industrial complex. The number of NASA contractors which do NOT participate in military procurement is very small, if I am not mistaken.<br /><br />With a budget approaching 600 billion dollars a year without Iraq war costs, the military is becoming very expensive to support. Taking 50 billion a year out of that budget to devote to a lunar base would push the development of new technology much faster than current military research is. It would also create opportunity for companies like ATK to make money doing honest work.<br /><br />Of course, we can just wait until Boeing is the military-industrial complex, because they would probably start their own space program. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>
 
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jimglenn

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U guys should just buy a few Long Marches from the dolla stores over there. They got one that can lift 25 tons. And they did it right, with liquid booster strapons!<br /><br />But I would convert to cryo fuels to get the max ISP.<br /><br />Save some money! <div class="Discussion_UserSignature"> </div>
 
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holmec

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<blockquote><font class="small">In reply to:</font><hr /><p>The propellant grain must be changed anyway<p><hr /></p></p></blockquote><br /><br />I'm glad to hear that. I wonder if they will consider reconfiguring the internal of the SRB. That is have like two combustion holes instead of one? Probably not, that idea is pretty out there. <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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