BIG problems with Ares I - "the stick"

[subzero788]

"Hey, could you modify a Falcon V to launch an Orion capsule?"<br /><br />Well, no, because the Falcon 5 can only deliver just over 4mT to LEO. Perhaps you meant the Falcon 9? The standard Falcon 9 can deliver about 8.7mT to LEO however SpaceX have projections of upgrading it to carry almost 25mT, in the range of the projected mass of the CEV. <br /><br />However, we are talking about a non-existent vechicle. This is like saying the Atlas V or Delta IV could be upgraded to carry the CEV. In fact it's worse because both these vechicles have a respectable record of 8 or so launches, yet the Falcon 9 has yet to be flown. Therefore the chances of the CEV ever launching on a SpaceX vechicle seem pretty damn unlikely.

 

[rfoshaug]

<blockquote><font class="small">In reply to:</font><hr /><p><blockquote><font class="small">In reply to:</font><hr /><p><br /><br /> That same document says:<br /><br /> "An example of the activity was a review and analysis that confirmed the planned Ares I launch system has sufficient thrust to put the Orion spacecraft in orbit."<br /><br /> So - no problemo.<br /><p><hr /></p></p></blockquote><br /><br /><br />I feel so much better now that a NASA INTERNAL MEMO, a.k.a., not for public release, but "somehow" made it to the public, stating as such.<br /><br />I can sleep easy now <img src="/images/icons/wink.gif" /> <p><hr /></p></p></blockquote><br /><br />You may believe in it or not, but from NASA we have a statement that says that everything is under control.<br /><br />My post was an answer to gunsandrockets' post. He read in that same memo that the Orion was getting heavier and claimed that as Ares I and Orion are in trouble because of this. But when another paragraph states that Ares I will be able to put Orion in orbit, then you can't use that same memo to argue the opposite, in my opinion. <div class="Discussion_UserSignature"> <p><font color="#ff9900">----------------------------------</font></p><p><font color="#ff9900">My minds have many opinions</font></p> </div>

 

[baktothemoon]

"Therefore the chances of the CEV ever launching on a SpaceX vechicle seem pretty damn unlikely."<br /><br />Still, I would rather have NASA try to launch on a Space X rocket rather than build a completely new rocket or build "stumpy".

 

[rfoshaug]

There are a lot of people claiming that using existing (or modified) EELV's would be a better way of putting Orion into orbit. Here's my 2 cents:<br /><br /><br />Technically, it would work just fine. But here's the problem: If NASA chose some variant of either Atlas V or Delta IV to launch Orion, first of all it would have to be human rated. This would not come for free. NASA would not be able to afford simultaneous development of Ares V in parallel with paying Lockheed Martin or Boeing for re-engineering, re-certification and testing of this launch vehicle, all at the same time as flying the shuttle until 2010. It's not very likely that the development of Ares V would start much sooner than it will with NASA taking the Ares I route.<br /><br />This would mean that those working at ATK (manufacturer of the SRB's) would not be able to develop the 5-segment booster for quite a while (unless this would also happen at the same time as man-rating an EELV). This would be a very difficult transition for ATK, and they might even have to lose some of its workforce while waiting for Ares V. Important competence could be lost with the effect of actually <i>delaying</i> Ares V and lunar missions instead of speeding them up.<br /><br />Since the 5-segment booster and J-2X engine are to be used on Ares V, they will have to be developed anyway, and when this is done you have the major parts of an Ares I. Paying for EELV's on top of this would be a waste.<br /><br /><br /><br />Then there are those that support the Direct idea (www.directlauncher.com). The basic idea is to develop one medium-lift (70-80 metric tonnes) launcher instead of the small Ares I (Orion spacecraft with service module only) and the gigantic Ares V (130 mT). In Direct, Orion and the lunar lander would be launched together in one launch, and the Earth Departure Stage in another.<br /><br />First of all, this makes a simple LEO launch of Orion quite expensive (you use 2 4-segment boosters and 2 RS-68R engines on a simple O <div class="Discussion_UserSignature"> <p><font color="#ff9900">----------------------------------</font></p><p><font color="#ff9900">My minds have many opinions</font></p> </div>

 

[gunsandrockets]

"My post was an answer to gunsandrockets' post. He read in that same memo that the Orion was getting heavier and claimed that as Ares I and Orion are in trouble because of this. But when another paragraph states that Ares I will be able to put Orion in orbit, then you can't use that same memo to argue the opposite, in my opinion."<br /><br />The point I was trying to make was the numbers coming out of NASA seemed to be all over the map and contradict each other, so there is nothing inconsistent if I point out numbers showing apparent weight growth despite NASA's insistence that all is fine with the stick. Also my post did not lift anything out of context and I noted the NASA claim about excess lift capacity of the stick.

 

[gunsandrockets]

"There's a difference between takeoff weight and insertion weight. Takeoff weight may inclue the LAS, for instance. We already know that bit is 3-5t."<br /><br />Good catch! That is the best explanation yet for the different numbers.

 

[gunsandrockets]

The problem with the 'systems engineering' as embodied by the ESAS plan of the CEV, Ares I and Ares V, is the plan is a big house of cards so that if one element fails the entire architecture collapses.<br /><br />The ESAS plan was supposed to be low risk, low cost, and to close the manned spaceflight gap from Shuttle retirement. Instead we get the first manned flight to ISS delayed until 2015, and have to swallow the costs of developing two virtually clean sheet launcher designs and two new engine development projects, plus build expensive new launch infrastructure and waste the significant pre-existing in-hand launch capabilities which overlap the Ares I.<br /><br />I have no doubt NASA can make the ESAS plan work given enough time and money, but the ESAS plan is not the best use of NASA's limited resources.

 

[gunsandrockets]

<br />This story has some interesting new details on the CEV.<br /><br />http://www.space.com/spacenews/businessmonday_061120.html<br /><br />NASA claims the current mass of a fully fueled CEV is only 17.6-18.7 tonnes! 15%-20% below program maximum allowable mass.<br /><br />Well isn't that interesting. That's a much more reasonable mass than the original ESAS plan which had a CEV mass of 23 tonnes.<br /><br />I wonder what the current capsule mass is? 7 tonnes?

 

[JonClarke]

I believe that 20% mass margins are required in many spacecraft designs.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[nyarlathotep]

<font color="yellow">NASA claims the current mass of a fully fueled CEV is only 17.6-18.7 tonnes! 15%-20% below program maximum allowable mass. </font><br /><br />Yeah, so did Airbus. Then they found out that all those tiny little lines on their CAD drawings representing copper wiring, connectors, wiring panels, raceways and bends in wiring looms actually had a non-trivial mass.

 

[nyarlathotep]

<font color="yellow">I have heard the sentiment expressed that "the stick" is archaeology. Maybe we need to ressurect the old Wehrner Von Braun NASA. </font><br /><br />We can't. Bush axed the cloning and stem cell research budgets. Even with the research money, I'm not sure there would be enough DNA left when we dig up his remains.

 

[propforce]

<blockquote><font class="small">In reply to:</font><hr /><p>I also have confidence in Griffin and NASA, and if they say everything is coming nicely along in the development of Ares I and Orion, I choose to believe them. <p><hr /></p></p></blockquote><br /><br />Did you believe in President Bush when he said there was WMD in Iraq? <img src="/images/icons/laugh.gif" /> Many of us did.. including me. That's because we the average citizens have no insight & infomation except choosing who we believe.<br /><br />Not so in this case with the Ares 1 ... and Ares 5 ... especially with many posters/ readers who're knowledgeable with this industry.<br /><br />Both using the EELVs and the Direct Launch concepts are good ideas, better ideas than the Ares 1. NASA is spending unncessary money and taking on unnecessary risks with the Ares 1. <br /><br />But you can choose to follow blindly, or you can use your God-given intellect and decision-making gifts. The choice is yours. Just don't complaint about NASA in the future if you choose to follow blindly. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> </div>

 

[PistolPete]

Speeking of the DIRECT launcher, the only problem I had with it was that it seemed too much for ISS servicing missions (which was the main reason for the Stick). But when I looked through the PDF again that I downloaded from their web site, I noticed that they had a European Space Agency ATV cargo module in the ISS servicing layout. Every time I look at it, DIRECT seems better and better. <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>

 

[radarredux]

> <i><font color="yellow">the only problem I had with it was that it seemed too much for ISS servicing missions (which was the main reason for the Stick)</font>/i><br /><br />IIRC, the current approach has several advantages over the direct method.<br /><ol><br /><li>A faster path for an indepent means to access space in general and ISS specifically for the US.<br /><li>Right size for ISS.<br /><li>Separate cargo from crew for safety reasons.<br /></li></li></li></ol><br /><i>In theory,</i> with a simpler design the Ares I will have a smaller chance of failure than the Ares V. Remember, the entire Constellation effort rose from the ashes of the Columbia tragedy, so safety is an important consideration. I suspect the operations will look like this: launch EDS and lander on the Ares V into LEO; do a complete remote check that all systems are go; and only then launch Ares I with crew to rendezvous with the EDS+lander.<br /><br />QUESTION: Would only the Ares I need to be man-rated? Would man-rating Ares I be easier than man-rating Ares V?</i>

 

[halman]

propforce,<br /><br />Yes, both the EELV and Direct would almost certainly work for the Orion, but we need to keep what few engineers there are remaining in the aerospace industry working, which means new designs. Of course, it doesn't mean that those designs will be used, just that money will be spent creating them.<br /><br />(Ok, I am being sarcastic.) <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>