Major changes of NASA's exploration plans

[radarredux]

> <i><font color="yellow">Yes, the 40% probability is faulty.</font>/i><br /><br />No, the statistics are quite correct [1].<br /><br />The probability of failure is<br /> Pr(failure) = 1.0 - Pr(success)<br /><br />The probability of success for one flight is 0.982; the probability of success for two flights is 0.982*0.982; three flights is 0.982*0.982*0.982; and in general, for 'X' consecutive flights:<br /> Pr(success) = 0.982^X<br /><br />Thus, the probability for failure is<br /> Pr(failure) = 1 - 0.982^28 = 0.399 (or 40%)<br /><br /><br />[1] The primary problem with the analysis is we really don't know what the probability of success is. 0.982 is just an estimate based on 2 failures for 114 flights. But from a statistics point of view (1) the numbers are way too low to make a reliable estimate, and (2) the conditions are always changing (e.g., new procedures, changes to the system, aging fleet, etc.).<br /><br />But, if 0.982 success rate is near accurate, then 40% probability of losing another shuttle before completing the ISS (and thus probably not completing the ISS) is correct. Also a bit sobering.</i>

 

[SpaceKiwi]

<font color="yellow">The key is that Griffin has come up with a way to bridge the ridiculous four year gap in the manned space flight program.</font><br /><br /><br />I still contend that there will not be a four year gap in US manned spaceflight. Although it might generally be agreed that a 2010 decommissioning is desirable for Shuttle, it hasn't yet achieved RTF and already one mission has slipped off the 2005 calendar into 2006.<br /><br />Again, although it is desirable that you get the CEV off the ground earlier rather than later, I think the Shuttle's retirement will slip back a little and CEV will move forward a little. There will be no gap in manned spaceflight operations.<br /><br />Don't discount the fact either that another five plus years of trouble-free Shuttle operations will make the urgency to retire it seem far less safety-critical. <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[SpaceKiwi]

<font color="yellow">All it takes is money.</font><br /><br /><br />This may be a dumb question, but does it really come down to just that? My initial thought is that money will help some, maybe even a lot, but wouldn't the biggest problem be the time needed for the engineers to figure out everything and build everything then test everything?<br /><br />Assuming you could hire as many as you wanted and had unlimited supplies of materials, testing facilities, computers, etc, how quick could you get the CEV done?<br /><br />And, in this safety conscious world we live in now, would the engineers feel happy they had covered all the angles if they built the CEV ASAP? For example, look at what has happened with the Shuttle and modelling airflow and debris pathes, etc. An incredible amount of work has been done in the last two years, which some might suggest should have been done before STS-1. Is that just a case of "there is some stuff you can only learn once you get operational"? <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[nacnud]

For the LM CEV that 40 tonnes is split into at least two parts. The CEV it's self as one part and the habitation module plus the propultion module. These could be sent up independedtly on EELV launches.<br /><br />I'm not saying thats the best solution, just that its possible.

 

[SpaceKiwi]

<font color="yellow">It is easy to forget that a lot of the computers and techniques taken for granted today, didn't exist in 1980!</font><br /><br /><br />Yeah, I hear ya news, I don't doubt that Shuttle was built with a fair few slide rules as well as some archaic computing grunt. <img src="/images/icons/smile.gif" /><br /><br />I'm just interested in what I perceive at least as the 'rush to CEV'. A fair few are all het up over the very slight possibility (in my view) that the US will be without manned access to space for a time. What was Goldin's catchphrase, 'Better, Cheaper, Faster' and the engineering response, 'pick any two'.<br /><br />It concerns me, from an entirely impartial viewpoint, that they get the CEV right rather than just get it built. I know many hold Apollo up as an example of what can be accomplished in a very short timeframe. And, impressive it was, to be sure. But, it didn't happen without a good measure of calculated luck, and did happen with the Russian Bear right on the US's tail a lot of the way.<br /><br />I'd rather see the US with the most amazing and robust space vehicle ever in 2014, than some 'it was almost good' vehicle in 2009. Your worst case scenario is that the Shuttle has to make a few more flights than you would like but, if you still have Discovery, Atlantis and Endeavour in your fleet come 2010 (which I am going to be positive and say you will), then where's the drama? <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[drwayne]

Don't forget, the LEM for example was a vehicle with some remarkably bad "flying" chaacteristics that they got flying with computers that were...welll...barely recognizable as computers by todays standards - even earlier than 1972. <img src="/images/icons/smile.gif" /><br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[drwayne]

"Griffin told congress that the end of 2010 is a hard deck."<br /><br />Somehow I think a pronouncement by *any* government official about *anything* in 2010 - well - I wouldn't take it *real* *real* seriously.<br /><br />lol at me...<br /><br />Wayne<br /><br />p.s. You can probably say the same thing about current time + 6 months <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[SpaceKiwi]

<font color="yellow">Griffin told congress that the end of 2010 is a hard deck. The manned Shuttle must be retired by then. That actually surprized me because I thought that the end of 2010 was a soft date.</font><br /><br /><br />Wow, I wasn't aware he said that, that's one helluva ballsy call for him to make. That sounds like lots of pressure on contractors to deliver a vehicle when it's needed rather than when it's matured and ready.<br /><br />Well, I will defer to all you engineers on this one, but I do hope the CEV will be done right. Lots of time to test, lots of time to sit around and consider the test results, lots of time to assure yourselves you have got it right and that all the 'tees' are properly crossed and 'eyes' are properly dotted. <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[drwayne]

"True, I guess Griffin...Mike...said what he had to say at the time."<br /><br />Which is why he is the head of a major agency - and I am a lab rat no one ever heard of. (I am saying that out of respect for him, and the humor of making fun of me - I am such a great target)<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[drwayne]

You see, I am the sort of weirdo that looks at his post total and says - wow - in a few more posts, I will have four 2's - thats a pretty good hand.<br /><br />This is after passing 111,111 miles on my odometer the other day - 6 of kind. I wonder if I will make it to 123,456?<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[drwayne]

I understand. If I don't find a way to learn from you - I am not going to be around - my family has a definite history of not surviving that heart attack, and I have let myself go to heck.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[spacefire]

this probably has something to do with Lockheed and Boeing now being partners in providing launch services.<br />No fly-off=no competition.<br />Probably each is going to receive contracts for parts of whatever they are planing to build in the interim.<br />The way NASA changes their collective (but tiny ) mind, nothing is ever going to get done.<br /> <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[wvbraun]

"Your link does not say NASA is looking to cut the 28 flights to 12.<br />Nice try but you mis quote the artical. "<br /><br />No, I don't. The article says NASA has been looking at 11 flights. Unless you mean by "misquote" that I said "12" instead of "11".

 

[wvbraun]

"No, the CEV requirements aloow it to use a Delta IV heavy or a Atlas V."<br /><br />The *current* requirements, yes. However, Griffin recently (a few days ago) said that he doesn't think the CEV will weigh less than 30 tons, and that's without any habitation or propulsion module. So the EELVs would have to be modified if they are to be used at all.

 

[wvbraun]

<br /><i>"And on the other end of the scale, we need to look at what new development makes the most sense. The CEV, with all that I want it to do, in terms of its ability to service space station and, later, go to the Moon, cannot be easily assumed to weigh less than 30 metric tons - the weight of the Apollo Command and Service Module stack (leaving aside the Lunar Module). It is not reasonable to suppose that vehicle that needs to carry maybe twice that many crew on some Earth orbital missions or have some cargo for some minor cargo and consumables, and have other missions, will weigh much less than that. A mass of that order will be at least several metric tons. It is, in effect, a shuttle replacement. Well, we don't have a vehicle today which does that job. So, the question going forward is, OK. you're going to have to do something new to do that job. What is that new thing? Will that be derived from general components at the NASA end or will that be an EELV upgrade? AS far as I am concerned its all about the money."</i>

 

[starfhury]

This might be good thing. Who knows what Griffin will choose. One thing is clear though is that he doesn't like the current CEV proposals he's seeing. They appear to fall below his expectations. I think he's going to keep hard to the 2010 shuttle cancellation date. The shuttle is seriously dangerous to fly. I think Griffin really would like to see a better alternative replacement for the shuttle. So I think what will happen is that the shuttle will not fly 28 missions but more likely 10 missions. I think what he really wants to do is drop the current orbiter from the shuttle design, but keep the SRBs and tank. Here's where it gets interesting. Instead of using the SSMEs on some other designs, it might be cheaper to say add a Delta IV core to the stack which would launch us a huge payload including payload to finish the ISS. The money saved here from the 18 missions not launched would go to build a better more robust CEV with possiblely its own new booster. <div class="Discussion_UserSignature"> </div>

 

[radarredux]

> <i><font color="yellow">Griffin told congress that the end of 2010 is a hard deck. The manned Shuttle must be retired by then. That actually surprozed me because I thought that the end of 2010 was a soft date.</font>/i><br /><br />It used to be "retire the shuttle in 2010 <i><b>when</b></i> ISS was complete." Lots of people have expressed doubts that the ISS could be completed by the end of 2010, so everyone focused on "when ISS was completed."<br /><br />Griffin is no fan of the ISS and the shuttle[1], has set a hard date of no later than 2010 for retirement (could be earlier?) [2], has expressed a willingness to change the ISS manifest [3] [4], has said the ISS may not be completed on time[5], and that means other than the shuttle may be needed to complete the ISS [6].<br /><br />Guys, wake up and smell the coffee. For the new administrator, the ISS and space shuttle are not Holy Relics to be protected at all costs.<br /><br />----------<br /><br />[1] "But the more important question is whether the return to be obtained from the use of ISS to support exploration objectives is worth the money yet to be invested in its completion. ... It is beyond reason to believe that ISS can help to fulfill any objective, or set of objectives, for space exploration that would be worth the $60 B remaining to be invested in the program."<br />http://www.spaceref.com/news/viewsr.html?pid=12151<br /><br />[2] Griffin's long-term goal #1: figure out the smartest path to retire the Shuttle by 2010 <b>and no later</b><br />http://www.spaceref.com/news/viewsr.html?pid=16293<br /><br />[3] Griffin's long-term goal #2: honor our obligation to our international partners to complete the International Space Station, <b>but this may involve reorienting the manifests</b><br />http://www.spaceref.com/news/viewsr.h</safety_wrapper</i>

 

[radarredux]

> <i><font color="yellow">One thing is clear though is that he doesn't like the current CEV proposals he's seeing. They appear to fall below his expectations.</font>/i><br /><br />I am not disagreeing with you on this, but could you provide some references, or at least reasons why you believe this is the case?</i>

 

[starfhury]

Well, he's calling for a top level re-evaulation of the entire program. Why bother if he liked what he saw already. http://www.spaceref.com/news/viewsr.html?pid=16512 <div class="Discussion_UserSignature"> </div>

 

[wvbraun]

Yes, but he initiated this review prior to recieving the CEV proposals. He probably already knew that the RFP document NASA put out in March would not produce the desired results.

 

[spacefire]

ywawn...<br /><br /><br />wake me up when something actually gets built...<br />it's gonna be a long nap. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[wvbraun]

Good night, troll.

 

[spacefire]

you certainly are oblivious to any form of sarcasm. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[jurgens]

It's not sarcasm when you do it in EVErY SINGLE post of yours.<br /><br />Grow up, Being Sarcastic to every single post out there doesn't make you intelligent, cool, or insightful, it just makes you sound like a troll.

 

[the_ten]

I don't know what's more annoying. A troll, or people calling someone a troll every time they respond.