Planetary Society releases exploration plan

[radarredux]

The Planetary Society, which had traditionally been against manned exploration of space (they preferred robotic exploration), seems to have really jumped on the new vision. They have produced one of the most detailed plans I have seen to implement the vision. Below are some links, with the full report PDF link at the end.<br /><br /><br /><b>Planetary Society Calls for 2-Step Crew Exploration Vehicle Development</b><br />Shuttle-Derived Heavy-Lift Launch Vehicle Should Follow Cost of Human Moon-to-Mars Program Estimated at $4.3 Billion Per Year<br />http://planetary.org/news/2004/cev-development0722.html<br /><br /><b>THE PLANETARY SOCIETY IS GOING ALL OUT TO TURN THE MOON TO MARS VISION INTO REALITY!</b><br />http://planetary.org/aimformars/initiatives.html<br /><br /><b>EXTENDING HUMAN PRESENCE INTO THE SOLAR SYSTEM</b><br />An Independent Study for The Planetary Society<br />http://planetary.org/aimformars/study-summary.html<br /><br />PDF of the report:<br />http://planetary.org/aimformars/study-report.pdf

 

[alokmohan]

Van Allen was pioneer and now he says after cold war it is meaningless to send man in space.

 

[radarredux]

I read the report last night (it is only about 30 pages), and it had some interesting points. Here were some of the items I found note worthy.<br /><br />o <font color="yellow">Three phase development</font> Phase I: A "block 1" variant of the CEV that can reach ISS by shuttle phase out in 2010 (I think NASA currently has a 2014 date for first CEV flight). Phase II: A "block 2" variant of CEV that can reach orbit of Moon and Mars as well as visit Sun-Earth Lagrange Point 2 (SEL2) and near-Earth objects (NEO) (like asteroids). Phase III: add landing craft that can land and return from the surfaces of the Moon and Mars.<br /><br />o <font color="yellow">Destination agnostic</font> Their approach is somewhat independent of a particular destination. Destinations and their order can be determined later based on scientific merit, political will, etc. The price of this flexibility is that landing humans on the surface of either the Moon or Mars is pushed back a number of years.<br /><br />o <font color="yellow">Cheap design</font> They use historical cost metrics to develop an expected cost in more detail than I have seen NASA deliver. The average price for their approach is about $4-4.3 billion per year, or roughly the cost of today's space shuttle program. I believe this is much less than what NASA was expecting to spend (NASA was planning on cannibalizing a number of NASA efforts (including science efforts) and was expecting an initial boost in funding).<br /><br />o <font color="yellow">SRB for CEV</font> One of the interesting suggestions was using an existing shuttle SRB as the booster for the first version of the CEV.<br /><br />o <font color="yellow">CEV for everyone</font> They encourage the development of a CEV that can be launched on a number of vehicles from a number of countries. This would encourage participation of other countries, would provide redundancy in case one booster has issues, and provides

 

[najab]

This is an idea that, quite frankly, scares me &%$#@!less. But many of the really great ideas are scary.<p>There's a seductive simplicity to that idea that just doesn't allow you to reject it off hand. Plus it just reeks of dirty-hands engineering. A real 'Tim-the-toolman-Taylor' <b>solution</b> to the problem. Forget designing and testing a new rocket - just strap the capsule on top of a million pounds of solid fuel and light the sucker!</p>

 

[nacnud]

It scares me too, I almost rejected the idea out of hand until I thought about it. I think it does have some good points.<ul type="square"><li> Uses already developed motors, SRB and SSME both with very good safety records.<li> Could be made 100% reusable.<li> Low cost as bits already developed just need bolting together in a new way.<br /></li></li></li></ul>I realise that it's going to be more complicated than that but I think that evaluating this against the heavy EELVs should be done, even if it only gets used as a freight delivery system. The idea of a common CEV that could be launched on various rockets also appeals and harks back to the Big Gemini mentioned in other threads on this page.<br />

 

[radarredux]

> <i><font color="yellow">This is an idea that, quite frankly, scares me &%$#@!less. ... Forget designing and testing a new rocket - just strap the capsule on top of a million pounds of solid fuel and light the sucker!</font>/i><br /><br />My first thought was, "How can they man-rate a solid rocket motor". Then I had the "Duh" moment when I realized that the shuttle relies on TWO of these every time it launches. Although, modifications (and I imagine recertification) will be needed.<br /><br />I like the idea of a quick solution (simple CEV on existing man-rated hardware) that you can build on for a more capable system later.</i>

 

[nacnud]

"Actually a Atlas V could do the job without going to the Atlas V Heavy (Atlas V 542 config. has a LEO payload of 41,000 pounds)"<br /><br />That’s great <img src="/images/icons/smile.gif" />, the Atlas V seems to have a cost of $110 M compared to the Atlas V heavy at $170 M from astronautica.com and I think the costs of the Delta 4 is comparable but I can't find a cost estimate of a SRB due to its reusable nature. How would a SRB compare for a single launch?

 

[najab]

><i>That and the new cryo upper stage and a requalified modified SSME is a large development cost.</i><p>Would it have to be an all new upper stage? Just off the top of my head, I'm wondering if an updated SIV-B wouldn't be cheaper to bring online.</p>

 

[najab]

Also, you wouldn't happen to know what the flight profile would look like? Would burnout still occur at about 20NM, or will it be higher since the SRB isn't hauling a million pounds of Orbiter and ET? What kind of staging velocity would we get?

 

[orzek]

I think using a solid rocket is insane, why can't they use a liquid fueled rocket, there are plenty on the market that can be updated for lauching the CEV.

 

[nacnud]

"In that study they said the 5 segment SRB would not be recovered. I believe this is due to the water impact loads being too high due to the added weight and length of the SRB."<br /><br />I can understand this if the same parachute was used in both the 4 and 5 segment SRBs but upgrading the parachute on the 5 segment SRB would be trivial so it must be something else. At the same impact velocity the five segment SRB would dive deeper due to the greater inertia and the relatively smaller frontal cross section area. The only thing I can think of is that the extra depth exceeds the crush depth of the five segment rocket. I find this unlikely and anyway it is something that I’m sure can be avoided by active measures such as airbags to decrease the density or braking rockets as used in Soyuz and MER to reduce the momentum on impact.<br /><br />If the system were to be made completely recoverable the second stage would need to soft land and be retrieved from the Indian Ocean. I’m sure that this could be an eventual goal but unless the launches were sufficiently numerous and frequent I doubt the savings could be made especially in the short term.<br /><br />So just for the sake of argument lets say that the whole system is retrievable only if the flight rate warrants it, can anyone make an educated guess about the cost of this compared to EELV derivatives if the stages are non-retrievable in both cases?<br /><br /><br />

 

[nacnud]

"why can't they use a liquid fuelled rocket"<br /><br />I'm sure they can, what I am interested to know is how much cheaper could this system be? IIRC there has been a call for NASAs budget to be set at a fixed amount rather than on a per project basis. This system might provide substantial cost savings especially if a matured system could be completely reusable. With a fixed budget any savings could be transferred to more launches as opposed to being clawed back at the end of the year.<br /><br />As an aside would a catastrophic failure of a solid rocket be any less escapable that a liquid fuelled one if given a suitable escape system?<br />

 

[mrmorris]

<font color="yellow">"In that study they said the 5 segment SRB would not be recovered."</font><br /><br />I know that most of us on this board like having 'techie' reasons for decisions like this, however, could it just be economics? I seem to recall reading that recovery and refurbishment of the SRBs is only <b>marginally</b> cheaper than simply building new ones. If the new/refit cost ratio changed at all -- they might just not be worth recovering.

 

[kdavis007]

Well Van Allen is a idiot.