Methane dropped from CEV plans

• #20 by Davros on 10 Jan, 2006 23:30
• Is it money or is it time delays? If there was enough money would we still be going with methane?
• #21 by Bruce H on 10 Jan, 2006 23:51
• A shame, but the reasons obviously are more important for the immediate goal. Like in the ESAS report, Mars was about 2 per cent of the document.
• #22 by Chris Bergin on 10 Jan, 2006 23:52
• Right, time to move this into the CEV section seen as the article is on site.
• #23 by Martin FL on 11 Jan, 2006 00:47
• Whatever it takes to keep the Moon shot in line. If not we could lose it all.
• #24 by SignalToNoise on 11 Jan, 2006 01:36
• I think they are trying to focus effort (and money) on the moon.
• #25 by Chris Bergin on 11 Jan, 2006 02:04
• Welcome to the site. Liking the login name!
  
  If that is indeed the case, then one could understand the reasoning behind protecting the Moon timelines and costs.
• #26 by Dobbins on 11 Jan, 2006 02:20
• One thing to keep in mind, the CEV is a modular system, it will still be possible to develop a Methane powered SM at some point in the future that can be placed behind the CM. This is one of the things I like about a modular system, you aren't locked into one design, a portion of it can be changed without having to redesign everything.
  
  
• #27 by David AF on 11 Jan, 2006 02:53
• That would be very useful, thus allowing for a changeout ahead of Mars missions with a methane utlized propulsion for when Mars comes around.
• #28 by Rob in KC on 11 Jan, 2006 02:56
• This is where we all tell Simonp he's a great guy, if he can get another link up on Slashdot!
• #29 by Dobbins on 11 Jan, 2006 03:06
• Any Slashdot member can submit a story to be included to the guys that run the site, but beware of the slashdot effect.
  
  http://en.wikipedia.org/wiki/Slashdot_effect
  
  The last story was linked on the weekend so the full fury of a weekday slashdot effect wasn't felt.
  
  
• #30 by BogoMIPS on 11 Jan, 2006 03:15
• Quote

  Dobbins - 10/1/2006  9:20 PM
  
  One thing to keep in mind, the CEV is a modular system, it will still be possible to develop a Methane powered SM at some point in the future that can be placed behind the CM. This is one of the things I like about a modular system, you aren't locked into one design, a portion of it can be changed without having to redesign everything.
  
  

  
  Right on the head, Dobbins.  Since the LSAM descent module and SM are expendable pieces of the system, they can always revise the designs for Methane engines for later variants.  Even if they never go to a Methane-breather on these systems, they can continue developing those engines earth-bounf for when we get a lot closer to a Mars mission, and eventually use those engines on a few unmanned runs first.
  
  I think it's smart to focus on getting back to the Moon right first, then worry about ISRU for Mars when we get closer to actually going there.
• #31 by James Lowe1 on 11 Jan, 2006 03:22
• This site has very strong servers. It is designed for a future of much higher volume.
  
  The record on Saturday was 550 people on the forum at one point in time on the users online count, this part "There are XX other users online." With a lot of those signing up to the forum and downloading a 54mb video off another server we have, the FTP server. What is more interesting is the forum has a problem counting when it get busy. Everyone saw how many people came here, yet the Gimbal joint thread only had a couple of thousand views, we need to get that fixed.
  
  But the server stats which do count right had the site at 93,000 page impressions for Saturday, a one day record. The site had 2 seconds of downtime in the 24 hour period.
  
  Bring them here, we'll cope. Spread the word by all means. The site is not even a year old and the best form of being a member of the site is to spread a positive word to other people.
• #32 by MATTBLAK on 11 Jan, 2006 03:47
• Dropping Methane, especially for a CEV stored in Lunar orbit for 6-month missions, is a BIG mistake. Hypergolics aren't efficient enough and in Lunar orbit, let alone Mars orbit, LH2 can boiloff. This is a problem Methane (CH4) barely has. And deleting the methane requirement for the LSAM Ascent Stage means this vehicle wont be able to be upgraded for Mars ISRU use.
• #33 by MATTBLAK on 11 Jan, 2006 03:51
• 'Manana, manana' is a mistake: they should be aiming for the future ISRU from the beginning, otherwise all they'll get for the first Mars mission will be a 20-day stay 'flags & footprints' landing. On the other hand, I strongly suspect that'll happen anyway. Could this be part of the Shuttle/ISS budget crunch: taking away advanced engineering studies and related science"?
• #34 by Dobbins on 11 Jan, 2006 04:11
• So what would you cut to pay for the Methane engines?
  
  
• #35 by ADC9 on 11 Jan, 2006 05:06
• I think you asked that question for the purpose of proving a point, one that I agree with. There's nothing we can cut anymore - no luxury hampers in the NASA offices this year.
• #36 by To The Stars on 11 Jan, 2006 05:16
• At first I was upset that we now appear to be cutting into the CEV program, but after thinking about it, is Methane really all that great for the Moon! Moon shot, go with what you know. This needs to be right, in the style of STS-121 right, then we can say we've done that and shown the system works. Then spend some cash, change it out with LOX/methane propulsion, go to Mars.
  
  If you look at it from an engineer point of view, this is less risky.
• #37 by CuddlyRocket on 11 Jan, 2006 05:24
• We must remember that the CEV has more purposes than lunar missions. It is also the means of LEO access, in particular to the ISS, both in crew rotation and cargo supply.
  
  Congress is unhappy at the current two-year gap between the end of STS and the bringing into service of the CEV.  There is also a funding gap in the later years of the STS. Both these would probably be mitigated by not having to develop an entirely new engine, but to go with something known. The inferior performance of hypergolics is unlikely to be significant for LEO missions as the CEV's SM is over-specified for that purpose (it was sized on the basis of lunar mission requirements).
  
  As Dobbins says, the CEV (and the LSAM) is modular. Once it's up and running, time can be taken to develop Methane engines, which I agree would be desirable for long-stay lunar missions (hypergolics having lower Isp and Hydrogen being bulkier and far more difficult to store aboard for long periods). We are a long way from lunar missions, let alone long-duration ones, and even further from Mars missions.
• #38 by NASA_LaRC_SP on 11 Jan, 2006 06:02
• It will be LOX/LH2. Hypergolic = large costs in infrasture, storage, safety and this program is really getting to a critical mass point with the funding. Some of the guys believe we might even see Griffin resign, based on nothing more than his visable frustration with anything not to do with the transfer from STS to CEV.
  
  Never met him, so I'm not sure if he's stronger than he appears, but your all going to want O'Keefe back if the pressure gets too much. He's starting to give the air of a mad king at times. O'Keefe, I did like him. Stable and honest as they come. Griffin has a great idea of where he wants to go, but has found there's no money to do that. Now the panic button has been pressed and there's a sword lashing in all directions. Even the subject right here has not been spared from this sword. I do believe Mars is to be fully taken away from focus for the next 10 years, then re-evaluate.
  
  I'm reading this back and I hate to sound critical of Griffin. He's a clever, nice man from all accounts. I believe I'm trying to say that most men would buckle under this, I would! It's just that he actually sounds like he's buckling, he's showing this and it's being noticed and realized by too many of the people I work with and trust.  That's what worries me.
  
  Solutions are needed, not shouting like a principle at the people you need to help make it happen.
  Clarity, not a change of mind from the very ESAS you are supposed to be follow, at a time where money has been lost because of the change of mind.
  
  As I said to my wife before I came here, I really think we're heading for a train wreck unless someone fixes the track, and fast.
• #39 by lmike on 11 Jan, 2006 08:02
• Interesting insights.  Thanks.  But doesn't it seem like the right thing to do though at this point in time?  I mean he has to make decisions right here and right now, and also being besieged by the astronomers, the ISS life science aficionados, the space plane advocates, the Senator Hutchinson, the 'effing STS/ISS and its international obligations, the State department, and et cetera. et cetera...  Can't afford developing methane fueled engines on the timeline and on budget, so we drop 'em.  So, I tell you that now.  Makes sense, it seems.  No?  I kinda like that, the fellow thinks fast and makes decisions on the go.  Maybe I'm just unskilled in this.  You are right he's nowhere near O'Keefe who'd require an all stuff meeting and the wise council for a year to make a decision like that.  Mike just says "no" right into your face.  As and engineer I'd prefer that.  
  
  p.s. And I do hope he doesn't resign due to all the stress, we need you to be strong Mike.. Seriously.